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Whether via an adjustable kettlebell set or landmine attachment to immensely diversify your home gym, uniqueness paired with functionality truly excites us. And if there’s any nutrient that marries the two, it’s vitamin D—affectionately known as the “sunshine vitamin” and truly one-of-a-kind. 

Yes, you can find vitamin D in foods (like any nutrient). But it’s also sourced from sweet sunshine (unlike any other nutrient). Unfortunately, vitamin D deficiency1 is an emerging health condition worldwide and available data2 points out that 25% to 50% (or more!) of patients in clinical practice are deficient in the vitamin. This can increase the risk of broken bones, muscle weakness, and seizures, just to name a few. 

We absolutely encourage a foods-first approach and the great outdoors. But if you’re needing a vitamin D boost, like most of the world, look no further than this best vitamin D supplement round-up.

As a registered dietitian (RD), I personally evaluated the products on this list (as well as others our team researched). We had members of the GGR team, including personal trainers and certified nutrition coaches, personally test each of these products. Together, we rated each supplement on the formulation, dosage, price, and side effects.

Through applying our in-depth supplement testing methodology, we arrived at the best vitamin D supplements on the market by looking at these factors:

  • Formulation: Does it have at least 1,000 IU (25 micrograms) of Vitamin D3 and contain no added sugars or unstable oils?
  • Swallowability: Can it be easily swallowed?
  • Third-party testing: Does the company use third-party testing to ensure there are no banned/harmful substances?
  • Price per serving: Products gets a 4-5 out of 5 if the price per serving is $0.10 or lower.

Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider.

Best Vitamin D Supplements for 2025

Let’s Quickly Chat Vitamin D

Before diving straight into our top picks, let’s get a better understanding of vitamin D. At its essence, vitamin D is a fat-soluble vitamin3 essential for bone, immune, heart, and mental health. (The nutrient also plays other vital health roles that we’ll dive into in the next upcoming sections, so be sure to stick around.)

Vitamin D is also very unique in that not only is it sourced naturally from foods, but also from glorious sunshine—which is why vitamin D is also known as the “sunshine vitamin.” The vitamin D we get from sun exposure is known as vitamin D3, although vitamin D2 is another form of the vitamin. 

Vitamin D2 vs Vitamin D3

Vitamin D primarily exists in two forms: vitamin D2 and vitamin D3. While their structures and uses are similar, the potency of vitamin D2 and vitamin D3 appears to be different. Bear with us here—while the differences are subtle, they make a world of difference in which form might be best to supplement with. 

We’ll first discuss vitamin D3, also known as cholecalciferol, for explanation purposes. Vitamin D3 naturally occurs in a select few food sources—like fatty fish, egg yolks, and fortified products such as cereal—but is mainly synthesized by the human body, especially when skin is exposed to sunlight.

Vitamin D2, or ergocalciferol, is also synthesized by sunlight but by plants instead of the human body. What this means is that plants—such as mushrooms and yeasts—synthesize vitamin D from the sun and humans can obtain vitamin D2 by consuming the aforementioned foods. 

Interestingly, both vitamin D2 and D3 are absorbed, metabolized, and used in the body similarly, However, older research4 shows vitamin D2 is much less effective in the body and that vitamin D3 is more effective in increasing blood levels of vitamin D in the blood. 

Overall, both vitamin D2 and D3 are functional forms of vitamin D and you could certainly get enough vitamin D from either. But, you would have to consume a lot more vitamin D2 to reach an adequate level—and what this really comes down to is a “work smarter, not harder” approach, and why you’ll notice all of our top picks include vitamin D3 as its primary form. 

All this said, let’s explore our (sun)shining vitamin D picks!

Best Vitamin D Supplement Overall: Transparent Labs Vitamin D3+K2

Good for: Anyone looking for a high-quality vitamin D supplement with added benefits of vitamin K2

Best Vitamin D Overall
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4.4
Transparent Labs D3 + K2
Plant-based
Non-GMO
Third-party tested
Vegan-friendly
30-day guarantee
Subscribe and save
Product Type
Vegan-friendly vitamin D supplement
Price Per Serving
$0.49 per serving, or less if you subscribe
Active Ingredients
Vitamins D3 and K2
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Goes Down Easy
This vitamin scored top marks for being tasteless and easy to swallow, plus no side effects, either
Pros
Third-party tested
Non-GMO and gluten-free
No artificial sweeteners or colors
Subscribe-and-save options
Cons
Contains coconut, an allergen
Only available in 60-count containers
Price per serving
$0.42
Key Ingredients
Vitamins D3 and K2
Total Servings
60
Vitamin D Content
125 mcg (5,000 IU)

Transparent Labs Vitamin D3 + K2 combines the two vitamins to maximize benefits. Each pill has 5,000 IUs of vitamin D3 and 100 mcg of vitamin K2. Customer reviews are limited but mostly positive for this product.

What our tester says:

“These pills are easy to swallow. They’re totally inoffensive, especially because they don’t give off an aftertaste or oily burps.”

Transparent Labs Vitamin D3+K2 is a high-potency plant-based vitamin D3 supplement in softgel form. It uses lichen as its vitamin D3 source to provide 5,000 IU (125 mcg) of vitamin D, or 625% of the recommended daily value. The amount of vitamin D you need daily is listed in both micrograms (mcg) and international units (IU), in which 1 mcg of vitamin D equals 40 IU.

It’s also formulated with 1,000 mcg of vitamin K2 from chickpeas. Vitamin K25 is a necessary part of heart, bone, and cellular function. This combination of vitamin D3 and K2 earns the Transparent Labs supplement a 5-out-of-5-star rating when it comes to formulation.

Transparent Labs Vitamin D3 K2

To enhance the absorption of the fat-soluble vitamin, the vitamin D3 and K2 supplement contains extra virgin olive oil. The starch-based vegetable capsule—made up of tapioca, glycerin, and water—may also protect the vitamin D and K2 within it when compared to animal-based capsules. 

GGR expert tester and senior editor, Erin Chancer, CNC, CPT, scores the Transparent Labs softgels 5 stars for taste, swallowability, and side effects. “These pills are totally inoffensive and don’t give off an aftertaste or oily burps,” says Erin.

While a tasteless and inoffensive pill is great, we also appreciate that Transparent Labs is well-known for their commitment to third-party testing and earns 5 stars in this category. Transparent Labs Vitamin D3+K2 formula is also free from artificial coloring, sweeteners, gluten, and GMOs. Third-party testing and pure ingredients means a higher price too (though you may be able to save some cash with a Transparent Labs discount code).

FormSoftgel
Vitamin D per serving125 mcg (5,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsTake 1 softgel 1-2 times daily with food
Cost per serving$29.99/60 servings = $0.49/serving 

Best High-Dose Vitamin D Supplement: Sports Research Vitamin D3

Good for: Those seeking a high-quality, effective dose of vitamin D

Best High-Dose Vitamin D
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4
Sports Research Vitamin D3
Gluten-free
Non-GMO
Third-party tested
45-day return policy
Subscribe and save
Product Type
High dose vitamin D supplement
Price Per Serving
$0.12 per serving, or less if you subscribe
Active Ingredients
Vitamin D3
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Vitamin D Deficiency
With 10,000 IU per serving, this high-dose vitamin D supplement will help people with deficiencies get back to normal vitamin D levels
Pros
Third-party tested
Non-GMO and gluten-free
Satisfaction guaranteed when purchasing directly from Sports Research
Cons
Contains coconut, an allergen
High-dose vitamin D isn’t needed by everyone
Contains gelatin from softgel
Price per serving
$0.12
Key Ingredients
Vitamin D3
Total Servings
120
Vitamin D Content
250 mcg (10,000 IU)

Sports Research Vitamin D3 is only available in one dosage, 10,000 IU. Be aware if you are allergic to tree nuts, as it also contains coconut MCT oil to help with absorption. This supplement is designed to support calcium absorption, bone development, and the immune system.

What our tester says:

“With a smooth exterior and small size, these softgels are very easy to take, and I like the third-party testing so I know that what I’m taking is free from contaminants.”

Sports Research high-dose vitamin D contains an impressive 5,000 IU per capsule which is ideal for folks who have limited access to sunlight. But if 5,000 IUs seems like a lot, you’re not wrong. The general recommendation for vitamin D is around 400 IUs. However, research published in the Journal of Bone and Mineral Research6 suggests that because sunshine can provide an equivalent of daily oral 10,000 IU, prolonged intake of high doses should not pose adverse risks. 

Another study from Mayo Clinic Proceedings2 suggests people with malabsorptive conditions—such as from a gastric bypass surgery—may require 50,000 IU of vitamin D once weekly or even daily to maintain sufficiency. And, for people with severe vitamin D deficiency, a “loading dose” of 50,000 once weekly (for up to three months) is a commonly applied strategy. 

Person holding bottle and one softgel of Sports Research Vitamin D

The bottom line is that a high-dose vitamin D supplement can be both safe and effective, especially when vitamin D status is monitored. This high-dose supplement earns a 5-star rating from our testers in the formulation category.

Our tester scored the Sports Research vitamin D softgels at 5 out of 5 stars for swallowability because they are super small and have a smooth exterior. Plus, these softgels are tasteless and formulated with MCT oil for added absorption. 

The Sports Research high-dose vitamin D supplement is certified gluten-free, non-GMO, third-party tested, and manufactured in a GMP compliant facility. Although it’s tested, it’s not done by one of the industry leading third-party labs, which is why it earns 4-star rating in this category.

FormSoftgel 
Vitamin D per serving250 mcg (10,000 IU)
Other active ingredientsNone
Dosing instructionsTake 1 softgel daily with food
Cost per serving$18.95/360 servings = $0.05/serving

Best Budget Vitamin D Supplement: Nutricost Vitamin D3 Softgels

Good for: Anyone looking for quality vitamin D on a budget

Best Budget Vitamin D
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4
Nutricost Vitamin D3 Softgels
Gluten-free
Non-GMO
Third-party tested
Made in a GMP-compliant facility
60-day money-back guarantee
Subscribe and save
Product Type
High-dose vitamin D supplement
Price Per Serving
$0.07
Active Ingredients
Vitamin D
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Vitamin D Deficiency
With 10,000 IU per serving, this high-dose vitamin D supplement will help people with deficiencies get back to normal vitamin D levels
Budget Shoppers
At $0.07 per serving, these vitamin D softgels are a steal
Pros
Affordable
Non-GMO and gluten-free
Easy to swallow
Cons
Not recommended on an empty stomach
Third-party testing lab not listed
Price per serving
$0.07
Key Ingredients
Vitamin D
Total Servings
240
Vitamin D Content
250 mcg (10,000 IU)

Nutricost offers an excellent price per serving value when it comes to Vitamin D3 supplementation.

What our tester says:

“I’ve definitely noticed a difference in my energy levels since starting to supplement with Nutricost.”

Nutricost’s Vitamin D3 supplement is a softgel option with budget top of mind. And when we say budget, we mean it—you can purchase 240 servings for about $0.07 (and that’s even without the subscribe and save options on Amazon). Because the cost works out to less than $0.10 per serving, the Nutricost vitamin D earns a 5-star rating price.

Low cost also doesn’t mean low quality, as it provides a whopping 10,000 IU of vitamin D3. It also contains a touch of the fat source sunflower oil to help aid in the absorption of vitamin D, and taking with a meal (especially with a fat source) can enhance the absorption as well. When it comes to forumulation, this budget pick earns a 5-out-of-5-star rating.

The vitamin D supplement is protected by a softgel capsule produced from gelatin and glycerin, so it’s not a vegan-friendly option. Don’t worry, though, we hand-picked the best vegan vitamin D supplement which will be featured later in this roundup. 

The Nutricost Vitamin D3 supplement is gluten-free and does not contain any added colors or artificial flavors. It’s also processed in a GMP-Compliant facility—meaning there are requirements on sanitation, personnel training, and quality control—and is recommended to be stored tightly closed in a cool, dry place to preserve vitamin D’s integrity.

“I found out a few months ago that I have low vitamin D so my doctor suggested I start supplementing,” says GGR Head of Content Nicole Davis, CPT, PN1-NC. “I’ve definitely noticed a difference in my energy levels since starting to supplement with Nutricost.” 

FormSoftgel 
Vitamin D per serving250 mcg (10,000 IU)
Other active ingredientsNone
Dosing instructionsTake 1 softgel daily with 8-12 oz of water
Cost per serving$17/240 servings = $0.07/serving

Best Vegan Vitamin D Supplement: Utzy Naturals Vitamin D3+K2

Good for: Plant-based eaters seeking a high-quality, effective dose of vitamin D

Best Vegan Vitamin D
Utzy Naturals Vitamin D3 + K2
Natural ingredients
Third-party tested
Made with natural ingredients
90-day empty bottle guarantee
Subscribe and save
Product Type
Vitamin D supplement
Price Per Serving
$0.54
Active Ingredients
Vitamins D3 and K2
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Natural Lovers
This product has been made with natural ingredients and is free of artificial colors and flavors
Pros
Well-reviewed by users
Made in the USA
“Empty bottle” return policy
Quality assurance guarantees
Cons
Pricey
Third-party testing lab not listed
Price per serving
$0.54
Key Ingredients
Vitamins D3 and K2
Total Servings
60
Vitamin D Content
125 mcg (5,000 IU)

Utzy Naturals contains a synergistic partnership of vitamins D3 and K2 in scientifically-backed dosages. It’s manufactured in the USA in an NSF-registered facility, is tested for purity and potency, and has an “empty bottle” guarantee.

What our tester says:

“This product is third-party tested, manufactured in the United States, and comes with an empty-bottle guarantee you won’t see with a lot of other supplements.”

Utzy Naturals Vitamin D3 + K2 provides an excellent way for plant-based eaters and vegans to supplement with vitamin D. The Pure Encapsulations supplement provides 125 micrograms (mcg)—or 5,000 international units (IU)—of vitamin D3 as cholecalciferol. 

The National Institutes of Health7 (NIH) indicates adults should get about 15 mcg (600 IU) of vitamin D daily and increase intake to 20 mcg (800 IU) at age 70 and older. However, the Endocrine Society8 states that to maintain adequate vitamin D levels, adults might need at least 37.5 to 50 mcg (1,500–2,000 IU) per day of supplemental vitamin D, and children and adolescents might need at least 25 mcg (1,000 IU).

Vitamin D2 is typically a plant-based dietary supplement source, as vitamin D3 supplements9 are often manufactured from animal products—therefore, not naturally vegan-friendly. But as we’ve covered, vitamin D2 isn’t as effective as vitamin D3, which can present a real challenge for those following a vegan-based diet searching for an effective vitamin D supplement. A popular way of creating vegan-friendly vitamin D3 is through lichen10, a complex life form of fungus and algae.

Now, we can’t confirm nor deny that Utzy Naturals uses lichen in their D3 formula. While their ingredient lineup is all vegan, there’s no official declaration, so you may want to proceed cautiously. That said, this product is third-party tested, manufactured in the United States, and comes with an empty-bottle guarantee you won’t see with a lot of supplements.

FormCapsules
Vitamin D per serving125 mcg (5,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsTake 1 capsule daily
Cost per serving$32.35/60 servings = $0.54/serving

Best Vitamin D Supplement for Men: Ritual Essential for Men 18+

Good for: Men seeking a high-quality, effective dose of vitamin D

Best Vitamin D for Men
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4.075
Ritual Essential for Men Multivitamin 18+
Vegan-friendly
Non-GMO
Third-party tested
Flexible delivery options
30-day money-back guarantee
Subscribe and save
Product Type
Multivitamin for men over 18 years of age
Price Per Serving
$1.23 per serving, or less in bulk or with a subscription
Active Ingredients
Vitamin A, vitamin D, vitamin E, folate, vitamin B12, magnesium, zinc, omega-3 fatty acids, boron, vitamin K2
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Active men
With added vitamin A, zinc, and boron, this multivitamin is formulated specifically with men in mind
Natural Shoppers
This multivitamin has traceable nutrients, is vegan-friendly and non-GMO, plus it has no synthetic colorants
Pros
Made Traceable with visible supply chain
Free shipping and money back guarantee with subscription
Delayed release capsule
Vegan-friendly
Cons
Pricier multivitamin
Some customer complaints about the mint flavor
Some ingredients are underdosed
Price per serving
$1.23
Key Ingredients
Vitamin A, vitamin D, vitamin E, folate, vitamin B12, magnesium, zinc, omega-3 fatty acids, boron, vitamin K2
Total Servings
30
Vitamin D Content
50 mcg (2,000 IU)

The Ritual Essential for Men Multivitamin 18+ is a well reviewed multivitamin with quality ingredients. The only notable complaint was the mint flavoring.

What our tester says:

“I like the minty essence, but I could see it being a bit overpowering on an empty stomach.”

Providing 50 micrograms of D3, Ritual Essential for Men 18+ (which also comes in formulas for women and men over 50) is a great option for those looking to get vitamin D as well as other key minerals and vitamins. Just to be clear, 50 micrograms is 250% of the recommended daily value of Vitamin D3, so it’s an excellent source to boost your vitamin D intake.

GGR product tester and certified personal trainer Anthony O’Reilly tested out the men’s formulation and rates the capsules a 5 out of 5 on taste and swallowability. He does warn, however, that “the minty flavor of the pills could be a bit much early in the morning on an empty stomach.” He also rates the multivitamin a 5 out of 5 on side effects, since he didn’t experience any during his testing.

Close-up of a hand holding a single gel capsule filled with a yellowish liquid, next to a loose capsule sitting on the counter and a clear bottle of Ritual Essential Multivitamin for Men 18+.

Both men’s and women’s formulations contain vitamin B12, vitamin E, folate, magnesium, vitamin K2, and omega-3 fatty acids. The men’s formula contains a few extra nutrients, however: vitamin A, zinc, and boron. Vitamin A is important in male reproductive health11 and zinc and boron aid in vitamin A and calcium absorption, respectively.

As a multivitamin, Anthony rates the formulation only a 1 out of 5. “There’s no chromium or selenium, and many of the ingredients are less than the recommended daily value,” he explains. Fortunately, vitamin D isn’t underdosed here. For the rest of these vitamins and minerals, this multivitamin should be used to supplement your micronutrient intake.

Ritual was a subscription-based company only, meaning you had to sign up for a monthly subscription for the vitamins. They’ve now opened up the ability to one-time purchase the vitamins, or you can buy a three-month supply in bulk. The subscription will help you save 10% each month; Ritual does offer a money-back guarantee and you can cancel your subscription at any time.

At over $1.20 per serving, Ritual Essential for Men is also a bit more expensive than other multivitamins. It earns a 4 out of 5 for price, however, since it’s not a terrible price—especially considering that they’re third-party tested. You can find out more about Ritual Essential and its different formulations in our Ritual Vitamins review.

FormCapsules
Vitamin D per serving50 mcg (2,000 IU)
Other active ingredientsVitamin A, vitamin E, folate, vitamin B12, magnesium, zinc, omega-3 fatty acids, boron, vitamin K2
Dosing instructionsTake 2 pills daily
Cost per serving$37/30 servings = $1.23/serving

Best Chewable Vitamin D Supplement: Ora Organic Sol Food High-Potency Vitamin D3+K2

Good for: Those looking for a chewable vitamin D supplement made with organic, vegan ingredients

Best Chewable Vitamin D
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4.09
Ora Organic Sol Food High Potency Vitamin D3 + K2
Plant-based
Non-GMO
Third-party tested
Free shipping over $75
60-day satisfaction guarantee
Subscribe and save
Product Type
Plant-based vitamin D supplement
Price Per Serving
$0.83 per serving, or less with a subscription
Active Ingredients
Vitamin D3, vitamin K2
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Natural Shoppers
This vitamin D supplement is plant-based and doesn’t contain any GMOs, filler ingredients, added sugars, or artificial ingredients
Pros
Meets daily requirement of vitamin D
Uses MK-7 vitamin K2
Most users enjoy the flavor
Third-party tested
100% satisfaction guarantee
Cons
Only 1 flavor
Contains xylitol which can cause stomach upset
Price per serving
$0.83
Key Ingredients
Vitamin D3, vitamin K2
Total Servings
30
Vitamin D Content
125 mcg (5,000 IU)

Featuring 5,000 IU of vitamin D3 naturally-sourced from lichen and 100 mcg of vitamin K2 from chickpeas, Ora Organic Sol Food High Potency Vitamin D3 + K2 is a once-daily chewable vitamin with a satisfaction guarantee. Users love the ease of use and the fresh citrus flavor.

What our tester says:

“The citrus flavor is nice and pleasant, not too sweet or powerful at all. These chewable tablets chew right up and dissolve in your mouth, too. I had no issues.”

When you think chewable, you probably think gummy. But not all want a chewable supplement in gummy form, especially if it’s chock-full of added sugars. Ora Organic Sol Food High-Potency Vitamin D3 + K2 is a chewable tablet sweetened with xylitol, a natural plant-based sugar alcohol with fewer calories and a smaller effect on blood sugar levels. (Keep in mind that xylitol may cause stomach upset in some users.)

This doesn’t mean they aren’t sweet. GGR Senior Staff Writer Caine Wilkes, OLY, USAW-L1, gave these chewables a try and was pleasantly surprised, calling out its distinct citrus flavor and ultimately giving it a 4 out of 5 for taste. 

ora-sol-food-d3-k2-bottle

As for solubility, non-gummy chewables can have a reputation for being gritty or chalky and getting stuck in your teeth. That wasn’t the case with Ora Organic. Caine even gave the chewables a perfect score of 5 out of 5, saying, “It chews right up easily and dissolves in your mouth, too. I had no issues.”

We went a step further and asked GGR Expert Contributor Dr. Bob Iafelice, MS, RDN, LDN, for his opinion on the formula and shared, “The dosage of 5,000 IU vitamin D is consistent with the top supplements out there, and what most adults need. The addition of vitamin K2 (especially MK7—the best form) is very important as it directs the calcium (absorbed by D) to the right places in the body. I give it a 5.”

ora-sol-food-d3-k2-tablets-in-hand

High praise aside, Dr. Bob did have a statement (or two) about how Ora Organic promotes its products that we thought was too interesting not to share:

“Plant-based supplements are an alternative—they are not better than supplements that the vast majority of people take. Case in point here: They state, ‘The cleaner source of vitamin D3.’ So, are we led to believe that the thousands of other D and K products are unclean? They even disparage lanolin as ‘wool grease.’ Maybe they should be reminded that many lip balms, skin and hair care products, cosmetics, etc., are made from lanolin. It’s fine to promote plant-based products as an alternative, but to say that they are superior to non-plant-based is unsubstantiated—just my two cents.” End rant. 

Apart from branding, we really like that Ora Organic High-Potency Vitamin D3 + K2 is gluten-free, certified vegan, USDA-organic, soy-free, dairy-free, and third-party tested. It also comes with a satisfaction guarantee and will grant you a full refund within 60 days if you’re unsatisfied with your purchase.

FormChewable tablets
Vitamin D per serving125 mcg (5,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsChew 1 tablet in the morning or by mid afternoon
Cost per serving$24.99/30 servings = $0.83/serving

Best Softgel Vitamin D Supplement: True Nutrition Vitamin D3

Good for: Active individuals looking for a vitamin D softgel that’s easy to swallow (price-wise too)

Best Softgel Vitamin D
True Nutrition Vitamin D3
Soy-free
Third-party tested
30-day return policy
Subscribe and save
Product Type
High-potency vitamin D supplement
Price Per Serving
$0.08
Active Ingredients
Vitamin D3
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Vitamin D Deficiency
With 5,000 IU per serving, this high-dose vitamin D supplement will help people with deficiencies get back to normal vitamin D levels
Budget Shoppers
At $0.08 per serving, these vitamin D softgels are a steal
Pros
Budget-friendly
Serving size is 1 softgel
Third-party tested
Soy-free
Cons
Third-party testing results only available by request
Manufactured in a facility that handles other food allergens
Price per serving
$0.08
Key Ingredients
Vitamin D3
Total Servings
120
Vitamin D Content
125 mcg (5,000 IU)

True Nutrition Vitamin D3 is a single-serving, potent vitamin D3 softgel, backed by third-party testing. It’s also budget-friendly and comes with 120 servings per bottle.

What our tester says:

“The softgels are small and very easy to swallow, especially since it’s just one at a time.”

Some things are hard to swallow—gas prices, disappointing final seasons (looking at you Game of Thrones), and pills. Literally, some vitamin tablets and capsules can be ridiculous in their size, or a serving consists of downing multiple pills at once. If you find taking vitamin supplements intimidating, you should try a softgel, like True Nutrition Vitamin D3.

The daily dosage is just one softgel; while we haven’t tested out this particular softgel ourselves, our experience with vitamin D softgels is that they’re typically smooth and have a smooth exterior. True Nutrition is the same, where even people who struggle with taking vitamins will have little to no trouble taking this supplement with a bit of water.

True Nutrition Vitamin D3 is simple. Each softgel contains 125 mcg (5,000 IU) of D3 from cholecalciferol, a fat-soluble compound. Furthermore, this is third-party tested, although the test reports are only available upon request. Still, you can rest assured that this vitamin D supplement is pure in its potency and contains a healthy dose of vitamin D to help battle off any deficiency you may have.

It should be noted that anyone with allergies may need to be careful. True Nutrition warns that their vitamin D3 is produced in a facility that also handles milk, soy, egg, nut, tree nuts, fish, and wheat products. While True Nutrition claims to be soy-free, they don’t claim to be free of any of these other allergens, so keep that in mind.

One of the biggest pluses of True Nutrition Vitamin D3 is its price. At about $0.08 per serving, True Nutrition is a budget-friendly vitamin D supplement, another way that this pill is “easy-to-swallow.”

RELATED: True Nutrition Discount Code

Supplementation—much like diet and exercise—is most effective when you’re consistent, so the cost, amounts of servings, and ease of use adds up to a potent vitamin D3 you can take every day with minimal effort to elevate your vitamin D levels and maintain the health of your bones, skin, and heart.

FormSoftgels
Vitamin D per serving125 mcg (5,000 IU)
Other active ingredientsNone
Dosing instructionsTake 1 softgel with food
Cost per serving$9.99/120 servings = $0.08/serving

Best Liquid Vitamin D Supplement: Athletic Greens D3 + K2 Liquid

Good for: Vitamin D seekers who prefer a liquid, mixable option 

Best Liquid Vitamin D
Athletic Greens Vitamin D3 + K2
Allergen-free
Non-GMO
Soy-free
High-concentration D3
Subscribe and save
Product Type
High-concentration liquid vitamin D supplement
Price Per Serving
$0.05, or less with a subscription
Active Ingredients
Vitamin D3, vitamin K2
Vitamin D Deficiency
With 1,000 IU per drop, this high-dose vitamin D supplement will help people with deficiencies get back to normal vitamin D levels
Budget Shoppers
At $0.05 per serving, this liquid vitamin D supplement is a steal
Liquid Convenience
Liquid vitamin D will be easier to ingest if you have issues with swallowing tablets or capsules
Pros
Affordable and can last for a long time
Non-GMO and allergen-free
Unflavored
Reportedly very effective
Cons
Dropper may make measuring dosage tricky
Price per serving
$0.05
Key Ingredients
Vitamin D3, vitamin K2
Total Servings
600
Vitamin D Content
25 mcg (1,000 IU)

If you are looking for an easy way to boost levels of vitamin D3 and K2, Athletic Greens’ Vitamin D3 + K2 liquid is a flavorless supplement that can easily be put in any beverage.

What our tester says:

“With the lack of sun in the winter I think supplementing with Vitamin D where I live plays a huge role in overall immune system health.”

Athletic Greens put itself on our map as one of the best greens powders on the market. But the brand also made its way as the best liquid vitamin D supplements, specifically in liquid form that provides 1,000 IU of vitamin D3 and 200 mcg of vitamin K2. This combination earns Athletic Greens a 5-star formulation rating.

According to the official Athletic Greens website, vitamins D and K2 “work synergistically to support the heart, vascular system, immune system, and respiratory system.” A 2017 study published in the International Journal of Endocrinology12 supports this, suggesting that joint supplementation of vitamins D and K might be more effective for bone and heart health rather than consuming either alone. 

While vitamins K1 and K2 are both beneficial, vitamin K1 is more involved with blood clotting and Vitamin K25 has pronounced roles in heart, bone, and really overall health. Vitamin K2 is under-consumed, though supplying high doses via supplementation could help consumers reach the required daily intake and improve their health.

An image of Athletic Greens Vitamin D3 K2

The D3+K2 liquid drops are also made with an olive oil base to augment the absorption of both fat-soluble vitamins, as well as vitamin E to preserve freshness. GGR Senior Staff Writer Lauren Strong, CPT, said the liquid does feel a little viscous like olive oil, but because you only have to swallow a few drops, it’s not too bad. She gave it a 4.5-star swallowability rating.

“I honestly didn’t really notice much for side effects, but I fell off the wagon taking this supplement daily and I got sick about two weeks later,” Lauren says. “With the lack of sun in the winter I think supplementing with Vitamin D where I live plays a huge role in overall immune system health.”

FormLiquid drops
Vitamin D per serving25 mcg (1,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsTake 2 drops daily or as directed by a healthcare professional; may be put on a spoon or food or mixed in with other liquids
Cost per serving$29/600 servings = $0.05/serving

Best Gummy Vitamin D Supplement: Bulletproof A+D+K Gummy

Good for: Kids at heart with adult vitamin D needs 

Best Vitamin D Gummy
Bulletproof Vitamins A+D+K Gummies
Sugar-free
Third-party tested
Non-GMO
Free shipping on orders over $49
30-day money-back guarantee
Subscribe and save
Product Type
Gummy vitamin D supplement
Price Per Serving
$0.83, or less with a subscription
Active Ingredients
Vitamin A, vitamin D, vitamin K
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Flavor Lovers
This gummy earned top marks in taste from our testers, and you won’t feel any remorse having this, since there aren’t any added sugars
Pros
No added sugar
3-in-1 supplement
Science-backed ingredients
Cons
Taste isn’t for everyone
Difficult to open the jar
Sugar alternatives may cause GI issues for some
Price per serving
$0.83
Key Ingredients
Vitamin A, vitamin D, vitamin K
Total Servings
30
Serving Size
2 gummies

The Bulletproof Vitamin A+D+K Gummies provide potent doses of each vitamin in one gummy. With no added sugars, these gummies can be a nice alternative for those who struggle swallowing pills.

What our tester says:

“These are SO GOOD. I’m almost out of these gummies and I’m really sad about it.”

Bulletproof A+D+K Gummy is the one and only vitamin D gummy on our list. The Bulletproof A+D+K gummies provide the familiar ingredients vitamins D3 (50 mcg) and K2 (180 mcg), which we’ve learned could be a synergistic power duo. But how do vitamins A and K1 fit in?

Bulletproof’s website details the “three essential vitamins that help your body work better when taken together. Instead of taking a separate vitamin A gummy, vitamin K gummy, and vitamin D gummy, this is your one-stop-shop for bone, heart, and immune support.” 

RELATED: Bulletproof Coupon Code

Vitamin A13—also a fat-soluble vitamin—supports normal vision, the immune system, reproductive health, and growth and development. And as we just recently touched on, vitamins K1 and K2 are both beneficial but vitamin K14 plays a larger role in blood clotting and is often administered as a medication. This is why newborns receive a vitamin K1 injection shortly after birth: to prevent the potentially lethal vitamin K deficiency bleeding.

An image of Bulletproof vitamin ADK gummies

Vitamins aside, the orange strawberry-flavored gummies do not contain any added sugars. Instead, they are sweetened with the sugar alcohols xylitol and erythritol, as well as the natural sweeteners monk fruit and stevia leaf extracts. Bulletproof earns a 5-star rating from our testers when it comes to forumulation due to the low-sugar profile and unique vitamin combination.

“These are SO GOOD,” says GGR expert contributor Amanda Capritto, CPT, CES, CNC, CF-L1, CSNC, who scored the Bulletproof gummies 5 out of 5 stars for taste.

“I’m almost out of these gummies and I’m really sad about it. The Orange Strawberry flavor is so tasty and tropical. I look forward to taking these every day.”

While not totally obvious on the vitamin D’s product page, a little poking around the Bulletproof site tells us their supplements only contain high-quality and “clean” ingredients provided in science-backed doses. They’re also free of GMOs, dyes, soy, gluten, and artificial fillers. 

FormGummies (Orange Strawberry-flavored)
Vitamin D per serving50 mcg (2,000 IU)
Other active ingredientsVitamins A, K, and K2
Dosing instructionsTake 2 gummies daily, preferably with food 
Cost per serving$24.95/30 servings = $0.83/serving

Best Vitamin D and K Supplement: Thorne Vitamin D+K2 Drops

Good for: Vitamin D-rop searchers who prefer liquid over capsules and chewables

Best Vitamin D with K
Thorne Vitamin D+K2 Drops
Gluten-free
Soy-free
Third-party tested
Derived from natural ingredients
60-day satisfaction guarantee
Subscribe and save
Product Type
High-concentration liquid vitamin D supplement
Price Per Serving
$0.05, or less with a subscription
Active Ingredients
Vitamin D3, vitamin K2
Third-Party Testing
Yes
Athletes
Thorne is trusted by 100+ sports teams and US Olympic teams, and has many products that are NSF-certified for sport
Budget Shoppers
At $0.05 per serving, these vitamin D drops are extremely inexpensive
Liquid Convenience
Liquid vitamin D will be easier to ingest if you have issues with swallowing tablets or capsules
Natural Shoppers
Thorne D+K2 drops are dervied from natural colors and flavors
Pros
Easy-to-take liquid form
Clean ingredients with quality-assurance process
Easy to swallow
Flavorless
Affordable
Cons
Dispenser can be tricky
Reports of damaged packaging
Price per serving
$0.05
Key Ingredients
Vitamin D3, vitamin K2
Total Servings
600
Vitamin D Content
25 mcg (1,000 IU)

Thorne Vitamin D/K2 liquid supplement is a convenient and affordable way to increase your intake of both vitamin D3 and vitamin K2.

What our tester says:

“These drops are tasteless, and I love that you can mix it into a beverage. I find them easier than taking a pill everyday.”

Thorne Vitamin D+K2 Drops are a purposeful, synergistic blend of vitamins D and K2 to support bone, immune, and cardiovascular health. With each 2-drop serving, you’ll specifically be taking in 25 mcg (1,000 IU) of vitamin D3 and 200 mcg of vitamin K2. 

The vitamin D drops also contain MCT oil to enhance absorption, as well as mixed tocopherols to preserve freshness. It’s also free of gluten and dairy-free, devoid of artificial flavors, and recommended to be stored in a cool, dry place (and not refrigerated). 

To help ensure the accuracy of the dosed drops, the Thorne vitamin D supplement comes with a self-dispensing tip. The top disperses individual drops, which Thorne says you might experience a delay between them for safer dosing, though they also encourage dispensing onto a spoon before consuming can help you get the right dosage. 

An image of Thorne Vitamin D3 K2 liquid

GGR Head of Content Nicole Davis, CPT—who was initially supplementing with the Nature Made Vitamin D3 softgels—has since switched to the Thorne liquid vitamin D. She scored both taste and swallowability of this liquid vitamin D at 5 out of 5 stars.

“These drops are tasteless, and I love that you can mix it into a beverage. I find them easier than taking a pill everyday. And, I haven’t noticed any difference in benefits from the softgels I was taking, which is a good thing as I definitely noticed better energy when I first started taking vitamin D,” says Nicole.

According to Thorne’s website, the US-manufactured and FDA-regulated supplement brand is trusted by 45K+ healthcare professionals, 100+ sports teams, 10K+ pro athletes, and U.S. Olympic teams. Thorne is also an official collaborator with Mayo Clinic, as well as the official supplement partner of CrossFit and UFC. Thorne has several NSF-Certified for Sport products, and while their vitamin D and K drops aren’t one, their transparency still gets them a 4-star rating for third-party testing.

FormLiquid drops
Vitamin D per serving25 mcg (1,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsTake 2 drops one to three times per day or as recommended by your health-care practitioner; may be added to food or beverages
Cost per serving$29.00/600 servings = $0.05/serving

Best Organic Vitamin D Supplement: Garden of Life Vitamin Code Raw D3

Good for: Whole food advocates looking for a boost of vitamin D, probiotics, and nutrients

Best Organic Vitamin D
Garden of Life Vitamin Code Raw D3
Gluten-free
Non-GMO
Third-party tested
Organic ingredients
60-day return policy
Subscribe and save
Product Type
Organic vitamin D supplement
Price Per Serving
$0.33, or less with a subscription
Active Ingredients
Vitamin D3, omega-9, raw organic fruit and vegetable blend, raw probiotic and enzyme blend
Third-Party Testing
Yes
Athletes
With third-party testing, you can rest assured your supplement is free of contaminants or banned substances
Natural Shoppers
This vitamin D supplement is certified non-GMO and is packed with raw, organic ingredients
Pros
Clean ingredients
Third-party certified
Vegetarian
Added probiotics and enzymes
Cons
Dosage may be too high for some
Added probiotics may cause digestive problems for some
Price per serving
$0.33
Key Ingredients
Vitamin D3, omega-9, raw organic fruit and vegetable blend, raw probiotic and enzyme blend
Total Servings
60
Vitamin D Content
125 mcg (5,000 IU)

The Garden of Life Vitamin Code Raw D3 is a gluten- and dairy-free whole food vitamin D complex that also contains a healthy dose of probiotics and digestive enzymes.

What our tester says:

“These capsules do taste a bit plant-like when I have them, but it’s not off-putting by any means.”

Garden of Life Raw Whole Food Vitamin D is formulated with whole food nutrition and contains a heavy dose of vitamin D3—5,000 IU to be exact. With such a large dose, compared to other products on our list, it’s urged to consult your healthcare practitioner before starting the supplement.

Vitamin D might be the nutrient of interest, but it cannot be overshadowed by the other 20+ whole food ingredients it contains. For that reason, it earns a 5-star rating for its formulation. Kate Meier, GGR editorial team member, scored the capsule’s taste a 4 out of 5, saying, “You might notice a bit of a plant-like taste from the fruit and vegetable blend, but it’s not strong. I don’t think it’d be too much for most people.”

If the flavor is a bit much, it at least goes down easy. Kate rated the swallowability a 5 out of 5. “It’s just one capsule, and while the capsule may be large, it’s very easy to take, and I never had any issues,” she adds.

An image of Garden of Life Vitamin Code Raw D3

We’ll first note the vitamin D supplement is joined with omega-9—a lipid base sourced from organic green chlorella (a type of algae)—to promote absorption. It also provides a raw organic blend of live probiotics and digestive enzymes to further enhance the absorption of nutrients, although we also recommend checking out the best probiotics to optimize your gut and overall health.

The robust vitamin D formulation also contains an organic fruit and vegetable blend of apple, beet, and broccoli, amongst many others down the colorful alphabet. Their addition is intended to provide antioxidants, vitamins, and nutrient cofactors that help drive essential chemical processes in the body. 

The whole food supplement is also certified by the nonprofit B Lab to meet rigorous standards related to social and environmental performance, accountability, and transparency. It’s also certified non-GMO, gluten-free, and kosher and manufactured without high heat, synthetic binders, fillers, artificial flavors, artificial sweeteners, artificial colors, and other additives.

Garden of Life also prides itself on its traceability, meaning each ingredient can be traced back to its source, and partnering with charitable organizations and foundations. They were also the first vitamin and supplement brand to be Certified Carbon Neutral and are committed to sustainable practices. For this reason, Garden of Life earns a 5-star rating for third-party testing.

FormCapsule
Vitamin D per serving125 mcg (5,000 IU)
Other active ingredientsOmega-9, raw organic fruit and vegetable blend, raw probiotic and enzyme blend
Dosing instructionsAdults take 1 capsule daily or as directed by your healthcare practitioner; best when taken with a meal; capsule may also be opened and contents added to water or juice 
Cost per serving$19.94/60 servings = $0.33/serving

Best Vitamin D Supplement for Kids: Carlson Labs Kid’s Super Daily Vitamin D3+K2

Good for: Kiddos recommended to an effective and high-quality vitamin D supplement

Best Vitamin D for Kids
Carlson Kid’s Super Daily Vitamin D3+K2
Gluten-free
Non-GMO
Third-party tested
No artificial preservatives
Subscribe and save
Product Type
Vitamin D supplement formulated for children 4 years and older
Price Per Serving
$0.08, or less with a subscription
Active Ingredients
Vitamin D3, vitamin K2
Third-Party Testing
Yes
Kids
This supplement is formulated for children aged 4 years or older
Natural Shoppers
This vitamin D supplement is certified non-GMO and has no artificial preservatives
Pros
Non-GMO certified
Has both vitamins D3 and K2
No artificial preservatives
Cons
Rosemary extract is too fragrant for some
Price per serving
$0.08
Key Ingredients
Vitamin D3, vitamin K2
Total Servings
360
Vitamin D Content
25 mcg (1,000 IU)

Made in an FDA-registered laboratory, Carlson’s Kid’s Super Daily Vitamin D3 + K2 liquid supplement provides 25 micrograms (1,000 international units) of concentrated vitamin D3 and 22.5 micrograms of vitamin K2 per serving.

What our tester says:

“After a bad reaction with a couple other brands for my second child, I switched to this brand after reading reviews and seeing they were vegetarian and gluten-free. It worked great! I’ll be using this for my third child too.”

Carlson Labs Kid’s Super Daily D3 + K2 is formulated for children aged four years or older, specifically providing 25 mcg (1,000 IU) of vitamin D. The amount of vitamin D matches some of our picks for adults, so is this too much or just right for the kiddos?

The NIH recommends7 infants from 0-12 months get 10 mcg (400 IU) of vitamin D each day and graduate to an adult dose of 15 mcg (600 IU) at age 1. However, the Endocrine Society says that children one year and older require at least 600 IU daily to maximize bone health. 

The Endocrine Society further states at least 1,000 IU of vitamin D daily can help raise blood levels consistently. And under medical supervision, maintaining tolerable upper limits (UL) of vitamin D should be at least 3000 IU/d for children aged 4 to 8 and 4000 IU/d for everyone over 8 years of age. However, higher levels of 4000 IU/d for children 1 to 18 years old may be needed to correct vitamin D deficiency.

An image of Carlson Kid's Super Daily Vitamin D3 K2 in a spoon

Preventing and correcting vitamin D deficiency is essential at all life stages, but especially in growing children to support their growing bones and bodies. Adequate vitamin D also reduces the risk of rickets, a condition described as the softening and weakening of the bones, particularly in children ages 6 to 24 months.  

GGR Head of Content (and mom of three) Nicole Davis, is no stranger to Carlson vitamin D drops. “With my second we went through two different types of vitamin D before trying this brand…she had a bad reaction to others (we think), crying super duper hard, and was just so unhappy. Something did not sit right with her. In my delirium at 2 a.m. with a screaming newborn, I remember Googling vitamin D drops and reading reviews about these so I thought I’d try them. Voila!”

Nicole scored taste, swallowability, and side effects all at 5 out of 5 stars for these Carlson drops.

Carlson vitamin D supplement provides 22.5 mcg of vitamin K2 as well. While we’ve explored the benefits of vitamin K2 for adult health, a 2022 review14 examining the impacts of vitamin K2 on children’s health points out children have the highest vitamin K needs. Vitamin K2 is shown to be safe and effective for children and promotes bone health, blood clotting, and a healthy heart. 

The review further suggests that 45 to 50 mcg of vitamin K2 is an appropriate intake range for children, although the supplement contains about half of the vitamin K2 recommendations. Parents and caregivers can help fill in the remaining needs with vitamin K2-rich food sources15, including cheese, milk, and other fermented foods and animal products. 

Overall, even though everyone benefits from seeking medical assistance regarding their vitamin D and nutritional needs, it’s a critical step for children. Before starting this product, or any other supplement for that matter, please consult with your child’s pediatrician for their utmost safety. 

The D3+K2 supplement also contains MCT oil and an antioxidant blend—of d-alpha tocopherol and rosemary extract—to enhance absorption and freshness. The formulation comes in unflavored vegetarian drops, that can be added to food or a drink, to lower any intake resistance from the little recipient. 

Also rest easy knowing the kid’s vitamin D supplement is free of GMOs, soy, gluten, dairy, and artificial preservatives. It’s also tested to meet potency and purity standards. 

FormLiquid drops
Vitamin D per serving25 mcg (1,000 IU)
Other active ingredientsVitamin K2
Dosing instructionsChildren 4 years of age or older: take one drop daily or as directed by your healthcare professional 
Cost per serving$29.90/360 servings = $0.08/serving

Best Vitamin D Supplement for Black Women: Mela Vitamins Daily Essentials for Women

Good for: Women with darker skin who are likely to have vitamin D deficiencies

Best Vitamin for Black Women
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4.03
Mela Vitamins Daily Essentials for Women
Certified vegan
Gluten-free
Non-GMO
30-day return policy
Subscribe and save
Product Type
Multivitamin formulated for women of color
Price Per Serving
$1.33, or less with a subscription
Active Ingredients
Vitamins A, B6, B12, C, D, K, and E; folate; biotin; magnesium; zinc; ceylon cinnamon bark; lion’s mane extract; probiotic blend
Third-Party Testing
No
Women of Color
Mela Vitamins Daily Essentials is formulated specifically with women of color in mind, specifically addressing vitamin D deficiencies
Natural Shoppers
Mela Vitamins are certified vegan and non-GMO
Pros
Subscribe and save 15%
Science-based nutrients and ingredients
High customer satisfaction
Vegan and non-GMO
Cons
Pricier multivitamin
Some customers don’t notice much difference
Price per serving
$1.33
Key Ingredients
Vitamins A, B6, B12, C, D, K, and E; folate; biotin; magnesium; zinc; ceylon cinnamon bark; lion’s mane extract; probiotic blend
Total Servings
30
Vitamin D Content
60 mcg (2,400 IU)

Mela Vitamins Daily Essentials for Women is made by and for women of color. Specifically, the multivitamin contains high doses of vitamins D3 and B12 to help combat deficiencies and to support energy levels and healthy red blood cells, respectively. Additionally, this multivitamin has five strains of probiotics to help with gut health and digestion.

What our tester says:

“These multivitamins don’t taste very bad, so long as you don’t let them rest on your tongue for too long.”

One of the unique features of vitamin D is that it can be absorbed through the skin from sunlight; however, some studies suggest16 that melanin can inhibit vitamin D production and absorption in the skin. Therefore, darker-skinned men and women have a greater chance of being deficient in the sunshine vitamin. 

For women of color who may need to offset a vitamin D deficiency, there’s Mela Vitamins Daily Essentials for Women, a daily multivitamin made for and designed by women of color to aid in vitamin D deficiencies, with 60 micrograms of the vitamin—300% of your recommended daily value.

“I love the amount of vitamin D in this multivitamin,” says our product tester and registered dietitian Destini Moody. “Not only is science starting to show most of us likely need more than the current recommendation, but women with darker skin are much more likely to be deficient, so a megadose is awesome in a product like this.”

Along with vitamin D, there are other vitamins and minerals present, and all near or above the recommended daily value, earning Mela Vitamins a 5 out of 5 for its formulation. Among notable ingredients is vitamin B12, used in the body for healthy red blood cell formation17, and vitamins A and E, which can boost your skin health18. There’s even a probiotic blend of five strains to aid in gut health.

Destini rates the taste of the veggie capsules a 4 out of 5, saying that the capsules have a stale flavor. “If you don’t let them rest on your tongue for too long, it’s not too bad,” she adds. They can be a bit of a hassle if you have trouble swallowing pills, though; Destini rates the swallowability a 3.5 out of 5. “They aren’t huge by any means, but having to take two of them at a time wasn’t my favorite thing in the world,” she explains.

One last call out is the price. At $1.33 per serving, these are pricey—even for a multivitamin. Destini rates the price a 3 out of 5 and admits the price is steep, especially when these multivitamins aren’t third-party tested. “In their defense, though,” Destini adds, “the thoughtful formulation composed specifically for darker-skinned women is something you won’t find in many other places.”

FormVegan capsules
Vitamin D per serving60 mcg (2,400 IU)
Other active ingredientsVitamins A, B6, B12, C, K, and E; folate; biotin; magnesium; zinc; ceylon cinnamon bark; lion’s mane extract; probiotic blend
Dosing instructionsTake 2 capsules daily
Cost per serving$39.99/30 servings = $1.33/serving

Best Calcium and Vitamin D Supplement: Thorne Advanced Bone Support

Good for: People who want a supplement for bone health

Best Vitamin D with Calcium
Thorne Advanced Bone Support
Gluten-free
Soy-free
Third-party tested
60-day satisfaction guarantee
Subscribe and save
Product Type
Supplement formulated to support bone health
Price Per Serving
$0.25, or less with a subscription
Active Ingredients
Vitamin B6, vitamin B12, vitamin D, folate, calcium, magnesium, boron
Third-Party Testing
Yes
Athletes
Thorne is trusted by 100+ sports teams and US Olympic teams, and has many products that are NSF-certified for sport
Budget Shoppers
At $0.25 per serving, this is a fairly inexpensive supplement to add to your daily stack
Older Lifters
This is a supplement formulated to help strengthen bones, which is a more serious matter as we age
Pros
Science-backed ingredients
Inexpensive
Gluten-free, soy-free, dairy-free
Free of many major allergens
Subscribe-and-save options
Cons
Some customers dislike the use of B vitamins
Some customers report digestive issues
Price per serving
$0.25
Key Ingredients
Vitamin B6, vitamin B12, vitamin D, folate, calcium, magnesium, boron
Total Servings
60
Vitamin D Content
25 mcg (1,000 IU)

Thorne Advanced Bone Support is formulated to help support bone health, particularly people who need extra support, like those diagnosed with osteoporosis. This supplement contains calcium, magnesium, and vitamin D, all used to help support bone health. Additionally, this multivitamin is gluten-free and free of major allergens.

What our tester says:

“I’ve used Thorne supplements throughout my athletic career because of their rigorous third-party testing. I always am confident that their supplements are free of contaminants and banned substances.”

As established, vitamin D can be an important part of bone health as it helps the body better absorb the calcium needed to support healthy bones and potentially prevent osteoporosis. For those wanting a vitamin D supplement that’s geared toward improving and supporting bone health, there’s Thorne Advanced Bone Support.

In addition to 25 micrograms of vitamin D, Advanced Bone Support contains B vitamins, calcium, magnesium, and boron—all used to support bone health. A 2023 review19 suggests that calcium taken with vitamin D can increase bone mineral density, which can help prevent or reduce the symptoms of osteoporosis as you age.

While we haven’t tested out this bone health supplement yet, we’ve tried out Thorne supplements before and can recommend them because of their transparency and strong formulation of many products, like Thorne Creatine.

Many of Thorne’s products are also third-party tested, being NSF Certified for Sport. While Thorne Advanced Bone Support isn’t NSF-certified itself, Thorne is very transparent about their ingredients and formulations, screening all ingredients for contaminants, so you should feel confident in what you’re taking.

Aside from large doses of vitamins D, B6, and B12, other vitamins and minerals are underdosed, so this won’t be a good source for your daily requirements. Think of this as the name implies: It’s a support to your current diet. At $0.42 per serving, you won’t break the bank adding this to your current supplements and vitamins, either.

FormCapsules
Vitamin D per serving25 mcg (1,000 IU)
Other active ingredientsVitamin B6, vitamin B12, folate, calcium, magnesium, boron
Dosing instructionsTake 2 capsules daily
Cost per serving$25/60 servings = $0.42/serving

Best Vitamin D Supplement for Women: Ritual Essential for Women 18+

Good for: Women looking for a high-quality, effective dose of vitamin D

Best Vitamin D for Women
GGR Score
We test and review fitness products based on an independent, multi-point methodology.
4.125
Ritual Essential for Women 18+
Vegan-friendly
Non-GMO
Third-party tested
Flexible delivery options
30-day money-back guarantee
Subscribe and save
Product Type
Multivitamin for women over 18 years of age
Price Per Serving
$1.23 per serving, or less in bulk or with a subscription
Active Ingredients
Vitamin D, vitamin E, folate, vitamin B12, iron, magnesium, omega-3 fatty acids, boron, vitamin K2
Third-Party Testing
Yes
Athletes
Third-party testing means it’s safe for those who may be subject to drug testing
Active women
With added iron, this multivitamin is formulated specifically with women in mind
Natural Shoppers
This multivitamin has traceable nutrients, is vegan-friendly and non-GMO, plus it has no synthetic colorants
Pros
Transparent ingredients
Clinically studied
Delayed-release capsule
Vegan-friendly
Cons
Pricier multivitamin
Some customer complaints about the mint flavor
May cause indigestion
Price per serving
$1.23
Key Ingredients
Vitamin D, vitamin E, folate, vitamin B12, iron, magnesium, omega-3 fatty acids, boron, vitamin K2
Total Servings
30
Vitamin D Content
50 mcg (2,000 IU)

Ritual Essential for Women is a clinically-backed, vegan multivitamin made with nine high-quality traceable ingredients.

What our tester says:

“The minty flavor is quite pleasant; definitely preferable to a typical pill flavor! I also didn’t get any stomach issues that I typically do with other vitamin supplements.”

Providing 50 micrograms of D3, Ritual Essential for Women 18+ has a nice amount of vitamin D, as well as other key minerals and vitamins. Also available in a men’s formula, both provide a whopping 250% of the recommended daily value of Vitamin D3.

GGR product tester Frieda Johnson, CNC, tested these vitamins for our team. She said these were a great option because they didn’t hurt her stomach as much as other multivitamins usually do, which is why these earned a 5-star rating for side effects—because she didn’t experience any.

ritual essential for women multivitamin 2

The women’s formulation contains in addition to vitamin D:

  • Vitamin B12
  • Vitamin E
  • Folate
  • Iron
  • Magnesium
  • Vitamin K2
  • Omega-3

While we do appreciate the vitamin D content in this formula, as a multivitamin, Ritual lacks selenium and chromium, and doesn’t meet the recommended daily value of many of the other ingredients. For that reason, it earns a 1 out of 5 for formulation. It can still be used as a multivitamin, so long as you’re extra sure to get plenty of micronutrients in your diet.

Frieda scored these multivitamins 5 out of 5 stars for taste and swallowability. Frieda was thrilled to find that these capsules have a minty flavor. “It’s quite pleasant; definitely preferable to a typical pill flavor!”

Originally a subscription-only service, Ritual offers single purchase and bulk purchases (which save the most money). Whichever way you choose, they do offer a money-back guarantee, and you can cancel your subscription at any time.

These vitamins are a little more expensive than other multivitamins. However, they are third-party tested, which makes the price much easier to digest, much like these vitamins. (Plus, you might be able to save more with our exclusive Ritual promo code.)

FormCapsules
Vitamin D per serving50 mcg (2,000 IU)
Other active ingredientsVitamin E, folate, vitamin B12, iron, magnesium, omega-3 fatty acids, boron, vitamin K2
Dosing instructionsTake 2 pills daily
Cost per serving$37/30 servings = $1.23/serving

Other Vitamin D Supplements We Researched

Because there are hundreds of vitamin D supplements out, it’s nearly impossible to capture other great finds into one small, yet mighty list. Beyond our top picks, other vitamin D supplements we researched and approve include: 

  • Nordic Naturals Zero Sugar Vitamin D3 Gummies
  • TheraCal D2000 Bone Health Supplement
  • NATALIST Vitamin D3 Gummies
  • Source Naturals Vitamin D-3 Liquid Drops
  • Designs for Health Liposomal D Supreme Vitamin D

How We Picked and Tested the Best Vitamin D Supplements

We take our product reviews very seriously and the same goes for picking and testing the best vitamin D supplements on the market. To form our top picks, we specifically analyzed and factored in the following:

  • Vitamin D type: As we’ve mentioned, vitamin D3 shows to be the most effective for increasing blood levels of vitamin D. This said, we are preferential towards vitamin D3 and each of our chosen products contains this form. 
  • Additional ingredients: If additional ingredients are formulated with vitamin D, what’s the intention? The inclusion of extra virgin olive oil is a great example of this, as the fat source can help enhance the absorption of the fat-soluble vitamin. We also favor products with cleaner formulas that are free of artificial ingredients, fillers, and other lower-quality, unnecessary ingredients.
  • Supplemental form: Consumers differ on how they wish to take a supplement—such as a liquid or softgel—so we captured various supplemental forms to honor various preferences. 
  • Cost: While vitamin D supplements tend to be budget-friendly as a whole, we made sure to pick assorted price points to accommodate just about every personal budget. 
  • Manufacturing and testing: Because supplements are not tightly regulated, we always always prioritize products that have undergone tight manufacturing and testing practices. This includes compliance with the Current Good Manufacturing Practice (cGMP) set and monitored by the U.S. Food and Drug Administration (FDA).
  • Brand loyalty: Is the company committed to high-quality products? Do they strive to keep customers both informed and satisfied? Just as we’re loyal to our review process and consumers, we place major weight on brands that do the same. 

Benefits of Vitamin D Supplements

Some health benefits of vitamin D are familiar, but others are less obvious. Regardless, what vitamin D can do for the body and health is impressive and all backed by research. 

Supports Bone Health

One of the most obvious and notable functions of vitamin D is its critical role to build and support healthy bones. Vitamin D deficiency also increases the risk of rickets in children, as well as osteomalacia and osteoporosis in adults.

This is because the body needs vitamin D20 for calcium absorption; and without enough of each, the body will start pulling available calcium in the skeletal system and eventually weaken bones. Supporting data21 clearly indicates that inadequate vitamin D over long periods of time can lead to bone demineralization. 

An image of Ritual multivitamin.

A meta-analysis22 shows that vitamin D supplementation does not appear to improve bone health for those with adequate vitamin D levels. However, 2019 research23 advises that vitamin D intake of 800 IU per day—in tandem with sufficient calcium intake—is optimal for fracture prevention. 

Protects from Several Chronic Diseases

Chronic diseases24 are conditions that last one year or more—like heart disease, Type 2 diabetes, and cancer—and are the leading causes of death and disability in the U.S. Lifestyle factors, including diet and exercise, mainly contribute to the risk of chronic disease but vitamin D also shows to protect from the following:

  • Heart/cardiovascular disease: A 2014 meta-analysis25 suggests vitamin D supplementation might protect against heart failure in older adults. A supporting 2019 systematic review and meta-analysis26 shows supplementing with vitamin D may reduce blood cholesterol and triglyceride levels.
  • Cancer: Research27 proposes that low blood vitamin D is associated with an increased risk of 15 different cancers—including breast, colon, lung, and prostate cancers—whereas adequate vitamin D may reduce the growth and spread of malignant (cancer) cells. Another systematic review28 also found that vitamin D supplementation could reduce the risk of cancer death by 15%. 
  • Type 2 diabetes: Because vitamin D deficiency is linked to insulin resistance and type 2 diabetes, researchers continue examining if vitamin D supplementation could prevent or help manage the chronic disease. Although a 2017 review29 advises vitamin D supplementation cannot be recommended to prevent or improve Type 2 diabetes at this time, a recent 2022 study30 hints vitamin D could be effective in decreasing diabetes in adults with prediabetes. 

Promotes Muscle Function and Recovery

Along with bone health, vitamin D can be integral in maintaining and supporting muscle strength and function. Recent research31 has even suggested that vitamin D can promote muscle regeneration after an injury, including fiber damage from resistance training. Likewise, muscular atrophy and defects have been reported with those with severe vitamin D deficiency, according to a 2018 review32. The same review showed an association between low vitamin D and an increase in falls or limb weakness.

While more research needs to be done to demonstrate the impact of vitamin D supplementation on athletic performance, it certainly will benefit athletes to maintain healthy levels of vitamin D to get the most out of their training, muscle-building, and reecovery.

Bolsters Immune Function

The immune system helps the body defend against harmful invaders, and 2011 data33 suggests lower levels of vitamin D may increase the risk of infections. Cells of the immune system—like B cells, T cells, and monocytes—may also positively respond to vitamin D, thus bolstering immune function, especially in individuals managing an autoimmune disease. 

A more recent 2020 review published in Nutrients34 tells us that vitamin D shows to exert immunological activities on many immune system responses. There have also been associations between low levels of vitamin D and greater risks of immune-related health conditions, including psoriasis, multiple sclerosis, type 1 diabetes, and rheumatoid arthritis. 

Can Promote Digestive Health

While this is a growing field of study still, vitamin D has been associated with a healthy microbiome in the intestines, according to recent reviews35. A higher intake of vitamin D seems to have a positive impact in the probiotics in your gut, although studies have been a little mixed on how effective it is. More research should be done to determine the actual effects, but initial findings do seem promising.

Boosts Mental and Cognitive Health

Have you ever felt down in the dumps, only to get an instant mood and energy jolt after basking in the sweet sunshine? Well, not only can getting out in the sun boost your mood, but vitamin D supplementation might as well. 

Stamina running

A 2020 systematic review and meta-analysis36, covering 25 trials and 7,500+ participants, found that vitamin D supplementation can reduce negative emotions. The benefits may be more pronounced in patients with major depressive disorders and individuals with vitamin D deficiency, though the evidence appears promising. 

Furthermore, adequate vitamin D supplementation can the brain from inflammation and free radicals, which is linked37 to cognitive decline and degenerative disorders like dementia or Alzheimer’s disease. Healthy vitamin D levels can reduce your risk of these and other mental health disorders, too.

Supports Weight Loss

Fat loss is the byproduct of lifestyle factors, especially diet, and vitamin D might surprisingly play a role. Interestingly, obesity can increase the risk of vitamin D deficiency whereas weight loss can increase vitamin D levels according to a 2011 study published in The American Journal of Clinical Nutrition38

In a 2018 study39, researchers conducted a double-blind clinical trial on 50 overweight and obese women: one group received 50,000 IU of vitamin D per week while the other group received a placebo for six weeks. The group receiving vitamin D significantly reduced weight, waist circumference, and body mass index while increasing blood levels of vitamin D. 

A less recent, yet larger 2014 study40 prescribed over 200 overweight and obese women (aged 50-75 years) with a calorie-restricted diet and exercise routine—and half of the women received 2,000 IU daily of vitamin D3, or and the other half took a placebo. After one year, the researchers found women who repleted vitamin D stores experienced greater improvements in their weight loss. 

Sources of Vitamin D

There are different ways to get vitamin D; the most unique out of them (and easiest, depending on your location) is through natural sunlight. All you need to do is make sure your arms aren’t blocked by a long-sleeve shirt, and go out into direct sunlight in the middle of the day, and you’ll have your recommended amount of vitamin D in about 20 minutes.

Still, some locations might not get a lot of sunlight, and certain times of the year will also prove difficult to get direct sunlight. For those times, you may want to supplement vitamin D, or look to getting the nutrient in foods as well.

Vitamin D shows up in certain foods, and other foods can also be fortified with vitamin D. Here are common sources of vitamin D in foods we eat:

  • Egg yolks
  • Fatty fish like salmon or tuna
  • Cheese
  • Liver
  • Fortified foods like milk, cereal, or orange juice

Vitamin D supplements are also a viable option, and might especially be needed if you’re deficient in the vitamin.

Symptoms of Vitamin D Deficiency

There are many symptoms of vitamin D deficiency, but not everyone experiences all (or any) of these symptoms. If you suspect you are deficient in vitamin D, or another micronutrient, consult with your physician on the best course of action. Common symptoms can include41:

  • Muscle and/or bone pain
  • Muscle weakness
  • Fatigue
  • Depression
  • Brittle bones

Because of vitamin D’s role in bone health, in extreme cases, bones may become deformed or a person may develop bowed legs.

Dosing and Interactions 

While vitamin D supplements are mostly considered to be safe, you should still dose accordingly. Vitamin D can also interact with certain medications, which could pose serious risks and/or reduce the efficacy of the supplement or prescription. 

Dose Recommendations

The amount of vitamin D you need each day is based on Recommended Dietary Allowances (RDAs), or the average daily intake level to meet nutrient requirements. Provided by the National Institutes of Health7, the RDAs below indicate daily intakes sufficient to maintain bone health and calcium metabolism in healthy metabolism: 

AgeMaleFemalePregnancy & Lactation
0-12 months*10 mcg (400 IU)10 mcg (400 IU)
1-13 years15 mcg (600 IU)15 mcg (600 IU)
14-18 years15 mcg (600 IU)15 mcg (600 IU)15 mcg (600 IU)
19-50 years15 mcg (600 IU)15 mcg (600 IU)15 mcg (600 IU)
51-70 years15 mcg (600 IU)15 mcg (600 IU)
>70 years20 mcg (800 IU)20 mcg (800 IU)

*Recommendation based on Adequate Intake (AI)

Interestingly, too, a 2020 review27 hints there’s still debate on what level of vitamin D in the blood is optimal to achieve the health benefits of vitamin D. However, it’s likewise advisable to increase vitamin D intake—and have sensible sunlight exposure—to maintain levels.

To add more complexity to the matter, vitamin D testing can be expensive and not always supported as a screening tool2. For successful repletion of vitamin D, it’s prudent to mention who might be at the greatest risk of deficiency which includes:

  • People who cannot tolerate or avoid dairy products or follow a vegan diet
  • Those who are classified as obese
  • Individuals condition that impacts the digestive system, including Crohn’s disease and conditions that interfere with normal fat digestion
  • People who have undergone gastric bypass surgery
  • Darker-skinned individuals or those who are regularly fully-clothed/use sunscreen that blocks vitamin D absorption from the sun
  • Older adults, especially who spend more time indoors
  • Those who live in the northern hemisphere, especially when winter arrives and sun exposure lessens

All this said, recommended intake values also vary based on an individual’s vitamin D level. Someone with a significant vitamin D deficiency will require more vitamin D to replete those vitamin D stores. 

Interactions & Safety

It’s smart to consult with your doctor before taking any sort of supplement, especially if you’re taking medication. This is because there’s always a risk of drug interactions, which can make the prescription less effective and/or lead to unwanted—and sometimes dangerous and fatal—side effects. 

Mayo Clinic42 counsels the following medications can lead to possible interactions, including:  

  • Aluminum 
  • Anticonvulsants, specifically phenobarbital and phenytoin
  • Atorvastatin
  • Calcipotriene
  • Cholestyramine 
  • Cytochrome P-450 3A4 substrates 
  • Digoxin
  • Diltiazem 
  • Orlistat
  • Thiazide diuretics 
  • Steroids
  • Stimulant laxatives
  • Verapamil 

Beyond medication interactions, vitamin D supplementation shows to be safe and toxicity is rare13. Severe adverse effects have only been reported with very extreme intakes of vitamin D ranging from 15,000-42,000 mcg, which is well above natural intakes from food or supplements.

Still, most of the risks are related to vitamin D’s function of increasing calcium absorption—the more vitamin D available, the more calcium that’s absorbed, which can cause hypercalcemia. Defined as high calcium in the blood, hypercalcemia43 can cause bone pain, digestive complications, kidney stones and failure, depression, and other worrisome health concerns. 

It might sound like a broken record, but it’s genuinely important to seek medical guidance to help determine your unique nutrient needs. 

Buying Guide: What to Look for in Vitamin D Supplements

Whether you’re looking for additional guidance to choose between our top picks or venturing outside the list, lean on these expert tips to decide which vitamin D supplement is right for you.

An image of the best vitamin d supplements

Review the Formulation

The formulation is what you’ll actually be consuming, so it’s important to review it. Here’s what to look out for in a vitamin D supplement: 

  • Vitamin D form: Vitamin D supplements mostly contain one of two forms, including vitamin D2 (ergocalciferol) or vitamin D3 (cholecalciferol). Both are great sources of vitamin D but we do recommend choosing a supplement with vitamin D3 since it’s more effective in raising vitamin D levels in the blood. 
  • Vitamin D content: Most vitamin D supplements provide 1,000-2,000 IUs of vitamin D, although some offer higher doses. Ultimately, you and your doctor should explore together how much vitamin D might be best for your individual needs and select a dosage to match.
  • Added ingredients: Beyond vitamin D, review and consider additional ingredients in the supplement. For instance, some vitamin D supplements contain other nutrients such as vitamins A and K while others (outside of our picks) might contain unwanted fillers. 

Consider the Supplement Form

Would you rather consume the vitamin D supplement as liquid drops, softgels, or gummies? Pick a supplement form based on your preferences, as you’ll be more consistent in taking it if it’s in a preferential form. 

Factor in Your Dietary Needs and Preferences

Do you follow a vegan diet? Or perhaps you’re managing Celiac disease and needing a gluten-free option. Consider your dietary needs and/or preferences and choose a vitamin D supplement to match. 

Explore Verifications and Certifications

Exploring the product verification and certifications can give you great insight into what’s actually in the supplement. (And what’s not in the product.)

Look out for third-party testing verifications to best validate the product’s safety, purity, and quality. Also, check to see if the product holds verifications that are important to you like certified gluten-free and/or vegan. 

Investigate the Brand Behind the Product

Investigating the brand behind the product of interest can deepen your understanding of the brand’s standards and reputation. Areas that can provide great insight include: 

  • Return policies and 100% money-back guarantees
  • Customer reviews on the site’s main webpage, as well as on Amazon and other third-party seller sites if available
  • Customer service access or at minimum a contact form you can fill out—and actually get a response back

Taking this extra step can help you decide if you’re willing to support a company (and acquire your hard-earned dollars)!

FAQs About Vitamin D Supplements

Which form of vitamin D is best absorbed?

Research suggests vitamin D3 is the best form to take rather than vitamin D2. Both forms act and function similarly in the body, although vitamin D3 shows to be effective in increasing vitamin D levels. 

How much vitamin D should you take every day? 

How much vitamin D you should take depends on many factors, including your age and current vitamin D status. As a general rule, most males and females should consume 15 mcg (600 IU) of vitamin D daily and increase to 20 mcg (800 IU) after age 70.

Is it better to take vitamin D in the morning or at night?

When it comes to timing your vitamin D supplements, all that matters is to follow the dosing instructions. Some supplements require you take with a meal or a certain amount of water.

What is the difference between Vitamin D and Vitamin D3?

Vitamin D3, also known as cholecalciferol, is a form of vitamin D. Vitamin D is available in different forms, primarily D2 and D3. The two forms of vitamin D2 and D3 are both produced through sunlight exposure, making them very similar at a glance.

However, vitamin D3 is mostly discussed in vitamin D supplements because this form seems to be more potent and effective in the body than D2, although the studies with these findings are older4.

References

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  2. Kennel KA, Drake MT, Hurley DL. Vitamin D deficiency in adults: when to test and how to treat. Mayo Clin Proc. 2010;85(8):752-758. doi:10.4065/mcp.2010.0138
  3. Harvard T.H. Chan School of Public Health. (2024, May 9). Vitamin D. The Nutrition Source. https://nutritionsource.hsph.harvard.edu/vitamin-d/
  4. Armas LA, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab. 2004 Nov;89(11):5387-91. doi: 10.1210/jc.2004-0360. PMID: 15531486.
  5. Halder M, Petsophonsakul P, Akbulut AC, et al. Vitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease. Int J Mol Sci. 2019;20(4):896. Published 2019 Feb 19. doi:10.3390/ijms20040896
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  16. Young, A. R., Morgan, K. A., Ho, T. W., Ojimba, N., Harrison, G. I., Lawrence, K. P., Jakharia-Shah, N., Wulf, H. C., Cruickshank, J. K., & Philipsen, P. A. (2020). Melanin has a Small Inhibitory Effect on Cutaneous Vitamin D Synthesis: A Comparison of Extreme PhenotypesThe Journal of investigative dermatology140(7), 1418–1426.e1. https://doi.org/10.1016/j.jid.2019.11.019
  17. National Institutes of Health (2024). Vitamin B12 – Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
  18. Joshi, M., Hiremath, P., John, J., Ranadive, N., Nandakumar, K., & Mudgal, J. (2023). Modulatory role of vitamins A, B3, C, D, and E on skin health, immunity, microbiome, and diseasesPharmacological reports : PR75(5), 1096–1114. https://doi.org/10.1007/s43440-023-00520-1
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  24. CDC. (2024, October 04). About chronic diseases. Centers for Disease Control and Prevention. Accessed October 17, 2024 from: https://www.cdc.gov/chronic-disease/about/index.html
  25. ‌Ford JA, MacLennan GS, Avenell A, et al. Cardiovascular disease and vitamin D supplementation: trial analysis, systematic review, and meta-analysis. Am J Clin Nutr. 2014;100(3):746-755. doi:https://doi.org/10.3945/ajcn.113.082602
  26. Dibaba DT. Effect of vitamin D supplementation on serum lipid profiles: a systematic review and meta-analysis. Nutr Rev. 2019;77(12). doi:https://doi.org/10.1093/nutrit/nuz037
  27. ‌Holick MF. Cancer, sunlight and vitamin D. J Clin Transl. Endocrinol 2014;1(4):179-186. doi:https://doi.org/10.1016/j.jcte.2014.10.001
  28. Zhang Y, Fang F, Tang J, et al. Association between vitamin D supplementation and mortality: systematic review and meta-analysis. BMJ. Published online August 12, 2019:l4673. doi:https://doi.org/10.1136/bmj.l4673
  29. ‌Lips P, Eekhoff M, van Schoor N, et al. Vitamin D and type 2 diabetes. J Steroid Biochem Mol Biol. 2017 Oct;173:280-285. doi: 10.1016/j.jsbmb.2016.11.021. Epub 2016 Dec 5. PMID: 27932304.
  30. Pittas AG, Kawahara T, Jorde R, et al. Vitamin D and Risk for Type 2 Diabetes in People With Prediabetes. Ann Intern Med. Published online February 7, 2023. doi:https://doi.org/10.7326/m22-3018
  31. Latham CM, Brightwell CR, Keeble AR, Munson BD, Thomas NT, Zagzoog AM, Fry CS and Fry JL (2021) Vitamin D Promotes Skeletal Muscle Regeneration and Mitochondrial Health. Front. Physiol. 12:660498. doi: 10.3389/fphys.2021.660498
  32. Gunton, J. E., & Girgis, C. M. (2018). Vitamin D and muscleBone reports8, 163–167. https://doi.org/10.1016/j.bonr.2018.04.004
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  34. Charoenngam N, Holick MF. Immunologic Effects of Vitamin D on Human Health and Disease. Nutrients. 2020 Jul 15;12(7):2097. doi: 10.3390/nu12072097. PMID: 32679784; PMCID: PMC7400911.
  35. Bellerba, F., Muzio, V., Gnagnarella, P., Facciotti, F., Chiocca, S., Bossi, P., Cortinovis, D., Chiaradonna, F., Serrano, D., Raimondi, S., Zerbato, B., Palorini, R., Canova, S., Gaeta, A., & Gandini, S. (2021). The Association between Vitamin D and Gut Microbiota: A Systematic Review of Human StudiesNutrients13(10), 3378. https://doi.org/10.3390/nu13103378
  36. Cheng Y, Huang Y, Huang W. The effect of vitamin D supplement on negative emotions: A systematic review and meta‐analysis. Depress Anxiety. Published online May 4, 2020. doi:https://doi.org/10.1002/da.23025
  37. Anjum, I., Jaffery, S. S., Fayyaz, M., Samoo, Z., & Anjum, S. (2018). The Role of Vitamin D in Brain Health: A Mini Literature ReviewCureus10(7), e2960. https://doi.org/10.7759/cureus.2960
  38. Mason C, Xiao L, Imayama I, et al. Effects of weight loss on serum vitamin D in postmenopausal women. Am J Clin Nutr. 2011;94(1):95-103. doi:10.3945/ajcn.111.015552
  39. Khosravi ZS, Kafeshani M, Tavasoli P, et al. Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study. Int J Prev Med. 2018;9:63. Published 2018 Jul 20. doi:10.4103/ijpvm.IJPVM_329_15
  40. Mason C, Xiao L, Imayama I, et al. Vitamin D3 supplementation during weight loss: a double-blind randomized controlled trial. Am J Clin Nutr. 2014 May;99(5):1015-25. doi: 10.3945/ajcn.113.073734. Epub 2014 Mar 12. Erratum in: Am J Clin Nutr. 2014 Oct;100(4):1213. PMID: 24622804; PMCID: PMC3985208.
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