The Best Sugar-Free Protein Powder: 8 Low-Carb Protein Options for Any Fitness Goal

Whether you’re a seasoned fitness enthusiast or someone who’s brand new to building exercise, health, and wellness habits, you’re probably aware of the importance of adequate protein intake. For those who struggle to get enough protein from food, which is very common, protein powders are a great way to bridge the gap and increase your daily protein intake. The best protein powders, like whey protein, are packed with health benefits that can help you reach your goal. 

However, if you’re currently on a weight loss plan, or you’re simply looking to minimize your sugar intake, you may be looking for the best sugar-free protein powder. Despite many proteins using flavors like chocolate, vanilla, or cookies and cream, you can find plenty of sugar-free options that will meet your dietary needs. 

With so many options, choosing the right protein powder can feel overwhelming, so I’m here to help you out. I’ve been a fitness professional and certified nutrition coach for 12 years, and I’ve tried plenty of protein powders over the years. I also spoke with Destini Moody, a registered dietitian, who helped me answer a few questions about the nuances of sugar-free protein powder. 

To make this list, I used our extensive supplement testing methodology to find protein powders that have been highly scored by our testers. Each product on this list contains no added sugar, though they may contain small amounts of naturally occurring sugar, or carbohydrates from other sweeteners.  

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.

8 Best Sugar-Free Protein Powders

• Best Sugar-Free Protein Powder Overall: Transparent Labs Whey Isolate
• Best Unflavored Sugar-Free Protein Powder: Nutricost Whey Protein Concentrate
• Best-Tasting Sugar-Free Protein Powder: Cellucor Cor-Performance Whey
• Best Vegan Sugar-Free Protein Powder: Ritual Essential Protein 18+
• Best Natural Sugar-Free Protein Powder: Legion Whey+
• Best Sugar-Free Protein Powder for Weight Loss: Kaged Whey Protein Isolate
• Best Sugar-Free Protein Powder for Building Muscle: Ascent Whey Protein
• Best Sugar-Free Protein Powder for Sensitive Stomachs: Dymatize ISO-100

Best Overall Sugar-Free Protein Powder: Transparent Labs Whey Isolate

Good for: Anyone looking for a versatile, low-sugar protein powder for any fitness goal

Best Overall

Transparent Labs 100% Grass-Fed Whey Protein Isolate

GGR Score: 4.2

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Product Highlights

• High-quality whey protein isolate
• 28 grams of protein per serving
• 15 flavors to choose from
• $1.99 per serving

Pros & Cons

Pros

• High-quality protein
• No artificial sweeteners, food dyes, or preservatives
• Lots of flavors to choose from
• Good customer reviews
• Whey isolate may be easier to digest for some people
• Subscribe and save 10% plus free shipping

Cons

• Price per serving on the high end
• Some reviews complain that it's too sweet

Bottom Line

Our testers love Transparent Labs 100% Grass-Fed Whey Protein Isolate because we know exactly what's in it, and almost every flavor we've tried is a 5 out of 5 on taste. Yes, it's a little more expensive than other protein powders but you get what you pay for.

Transparent Labs 100% Grass-Fed Whey Protein Isolate earned the title of best overall sugar-free protein powder for several reasons. First is the protein content, which comes in at a whopping 28 grams per serving, while most protein powders contain anywhere between 20 to 25 grams. 

There are no artificial sweeteners or colors, and the protein is gluten-free and non-GMO. 

GGR performance editor and certified nutrition coach Anthony O’Reilly tried the seasonal Peppermint Hot Chocolate flavor and gave it a 5-out-of-5 rating for flavor, saying that it tastes like a candy cane dropped into hot chocolate. 

It’s worth calling out that the carb and fat content can vary by flavor, ranging from 0 to 2 grams of carbs and 0 to 2 grams of fat, but most flavors contain no sugar at all. A couple of the flavors contain 1 gram of added sugar, but since most flavors are sugar-free, this still made our list due to the high quality. 

We’re big fan of Transparent Labs because they live up to their name by listing all of their ingredients (as well as the amount by weight) and being third-party tested by Informed Choice, but we never take a company’s word for granted. We collaborated Ellipse Analytics, a third-party accredited lab, to analyze 150 protein powder samples. Transparent Labs Whey Isolate ranked Above Average when compared to its peers, and ranked Excellent in label purity and accuracy, pesticides, and phthalates and bisphenols (chemicals used in the production of plastic). Our Independent Testing Supplement Glossary breaks down all these terms.

Check out our complete Transparent Labs Protein Review to learn more.

Best Unflavored Sugar-Free Protein Powder: Nutricost Whey Protein Concentrate

Good for: Anyone looking for an unflavored protein powder they can mix with other supplements or baked goods

Best Unflavored

Nutricost Whey Protein Concentrate

GGR Score: 4.42

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Product Highlights

• 25 grams of whey protein concentrate per serving
• Available in 5 flavors, including unflavored
• High-quality ingredients and third-party testing
• Supports lean muscle growth and recovery after workouts

Pros & Cons

Pros

• Budget-friendly
• Non-GMO and gluten-free
• Manufactured in GMP-compliant facility
• Unflavored option only contains one ingredient, instantized whey protein concentrate
• Subscribe-and-save options
• Cost-effective price that starts around $0.87 per serving

Cons

• Whey concentrate may not mix as well as whey isolate
• Flavored options are higher in calories than other whey proteins

Bottom Line

Nutricost Whey Concentrate contains 25 grams of high-quality whey protein concentrate, available in five flavors. It's gluten-free, non-GMO, manufactured in a GMP-compliant facility, and third-party tested.

While many protein powder users enjoy the flavors, especially when mixing protein with water or milk, we know that plenty of our readers prefer unflavored whey protein. Unflavored whey is exactly what it sounds like—completely flavorless. While there may still be a neutral taste from the milk, unflavored proteins are generally very easy to “hide” in smoothies or baked goods. 

Nutricost is known for producing high-quality ingredients that won’t break the bank and its unflavored whey protein concentrate is another high-quality product. We haven’t tested this formula yet to rate the taste, but we’ve tested other unflavored whey protein powders, and they tend to taste quite similar. 

I’ve also personally used Nutricost Creatine for over five years with no issues, and we recently took a closer look at it in our Nutricost Creatine Review. Nutricost supplements are manufactured in a GMP-compliant facility and third-party tested, so you know you’re getting a product you can trust. 

Unsweetened whey proteins aren’t for everyone, and they’re not that great if you’re going to drink them plain. However, if you prefer to mix your protein into things like oatmeal, smoothies, or baked goods, and need a neutral flavor, this is a great option that’s very high in protein. 

This formula uses whey concentrate, a complete protein source, with no fillers, allergens, preservatives, or other sketchy things on the ingredient list. You get one single ingredient, whey protein concentrate, though the flavored options have other ingredients.

There is 1 gram of sugar from the whey concentrate itself, but 0 grams of added sugar. You can also order this in a variety of flavors on Amazon, though many of the flavored options are also higher in calories due to more carbs and fats.

For more, check out our in-depth Nutricost Whey Protein Concentrate review.

Best-Tasting Sugar-Free Protein Powder: Cellucor Cor-Performance Whey

Good for: Anyone looking for a delicious protein source with low sugar

Best-Tasting

Cellucor COR-Performance Whey Protein

GGR Score: 4.9

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Product Highlights

• Fast-digesting whey protein containing 24 grams of whey protein per serving
• Available in molten chocolate and whipped vanilla
• Each serving is 120 calories and is formulated with 5.25 grams of naturally occurring BCAAs

Pros & Cons

Pros

• Tastes good, according to reviews
• Mixes well
• 24 grams of protein per serving
• Large tub (70 servings)
• Low in carbs and fats per serving

Cons

• Contains sucralose
• Only two flavor options

Bottom Line

Cellucor COR-Performance Whey Isolate Protein Powder delivers 24 grams of protein in each serving and is available in two flavors.

While Transparent Labs may have won the No.1 overall spot for quality, Cellucor Cor-Performance Whey comes pretty close thanks to its fantastic flavors and taste. You’ll see 1 gram of sugar listed on the container but 0 added sugars, which is why we feel confident including it on this list. It’s sweetened using cocoa powder and sucralose. 

Now, while there isn’t a wide variety of flavors to choose from—just Molten Chocolate and Whipped Vanilla at present—Cellucor more than makes up for it with the quality and delicious taste of their protein powder. Our expert product tester Anthony O’Reilly, CPT, CNC, tried the Molten Chocolate and was excited to report that it’s “instantly [his] new favorite chocolate protein powder, bar none.” He adds, “I wouldn’t be able to tell this was a protein drink.” 

No surprises here; Anthony rated Cor-Performance a 5 out of 5 for taste. This is high praise from someone who has tested over 50 protein powders.

Cellucor also took home perfect scores for its solubility and value—it’s about $0.99 per serving, with each container holding an impressive 70 servings. It’s even less per serving when on promo. Currently, you can get it for as low as $0.79 per two-scoop serving.

Best Vegan Sugar-Free Protein Powder: Ritual Essential Protein 18+

Good for: Anyone looking for a plant-based protein powder

Best Vegan

Ritual Essential Protein Daily Shake

GGR Score: 4.13

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Product Highlights

• Organic pea protein powder
• 20 g of protein per serving
• Formulated to support adults 18-49
• Third-party tested
• 150 mg of choline per serving 

Pros & Cons

Pros

• Soy-free, gluten-free, and vegan-friendly
• No artificial sweeteners
• Complete amino acid profile
• Non-GMO
• USA-grown peas

Cons

• Only comes in one flavor
• Price per serving is on the high end
• Velcro bag closure ineffective

Bottom Line

Ritual’s Essential Protein Daily Shake has 20 grams of protein per serving and 150 milligrams of chlorine (to support brain and nervous system function). This protein powder from Ritual is third-party tested and Informed Sport Certified, which means this formula has been screened for over 250 banned substances.

Sugar-free protein powders don’t only come in the form of whey protein isolates, and Ritual has come out with a fantastic vegan protein powder for those who avoid dairy.

Plant-based protein powders can be tricky, especially when it comes to the flavoring. These proteins are generally derived from whole-food sources like peas, rice, soybeans, chia seeds, or brown rice, and may have a bit of a gritty texture to them, along with a stronger natural flavor. 

Masking the flavor of the plant ingredients without sugar is challenging, which is why Ritual Essential Protein 18+ made our list. Instead of sugar, it uses Reb M, a zero-calorie sweetener derived from sugar cane, along with organic monk fruit. The protein comes from organic pea protein, which contains both EAAs and BCAAs, although each serving contains 20 grams of protein and only 3 grams of carbohydrates, while other plant-based proteins like Orgain have 15 grams of carbohydrates.

RELATED: Orgain Protein Powder Review

GGR’s Senior Director of Content Kate Meier, CPT, USAW-L1, used this soy-free protein in her morning smoothies and said that while the aftertaste was noticeable, it wasn’t too overwhelming, and she was very impressed with the ingredient quality. She also scored this a 5 out of 5 for solubility, saying that it dissolved shockingly well in water and was very smooth, which isn’t common with plant proteins.

Compared to whey isolate proteins, this may not taste quite as good, and it’s on the pricey side at $2.66 per serving, but the quality is fantastic. If you’re looking for a great dairy-free protein with no added sugar, this is a solid option. 

Read our Ritual Protein Powder Review to learn our full thoughts, or you can watch our video review on Garage Gym Reviews Everything.

Video Review

Best Natural Sugar-Free Protein Powder: Legion Whey+

Good for: Anyone looking for high-quality ingredients with third-party testing

Best Natural

Legion Whey+

GGR Score: 4

Check Price Use code GARAGEGYM to save 20%

Product Highlights

• Sourced from small dairy farms in Ireland
• Over 5 g of BCAAs per serving
• Non-GMO and animal welfare approved
• Third-party tested for banned substances

Pros & Cons

Pros

• Low in carbs and fat but high in protein
• Natural ingredients
• Money-back guarantee
• Made with ethically-sourced milk
• Lots of flavor options
• Subscribe and save 10%

Cons

• Comparably high cost per serving
• May be clumpy when mixed
• Some customers thought flavor was too sweet, or in some cases lacked flavor

Bottom Line

Legion Whey+ is a clean, sustainable protein powder that also is macro-friendly and a great option for anyone looking for a clean protein supplement. Many of our testers have bought this with their own money because they love the taste and easy mixability.

The whey protein isolate used is “Truly Grass-Fed” milk, which means it comes from cows that spend most of their time outdoors, roaming and grazing on grass. It’s sweetened with stevia, and free from artificial chemicals, flavors, or colors. Most of the flavors have no added sugar, though a few have small amounts, like the cookies and cream flavor, which uses real gluten-free cookie bits. 

Not only is the quality high, but the taste is excellent. GGR Performance Editor Anthony O’Reilly gave the Cinnamon Toast Crunch flavor a 5-out-of-5 rating, and Lindsay Scheele also said it’s one of her favorite flavors, and she puts it in smoothies, oatmeal, or mixes it with water. 

I’ve also been using Legion Whey+ myself and can attest to the quality and taste. This mixes well, tastes fantastic, and doesn’t cause any bloating or side effects for me, which is not the case with many other whey proteins. 

Furthermore, Legion Whey+ is third-party tested for banned substances and potentially harmful substances. We took it a step further by collaborating with Ellipse Analytics, a third-party accredited lab, to test for pesticides, heavy metals, and more. Overall, it ranked in the top 50% of the 150 protein powder samples we tested, and in the top 10% for pesticides and chemicals found in plastics. We explain our testing processes in our Independent Supplement Testing Glossary.

The only reason it’s not higher on the list is due to its cost, which can be high if it’s not on sale, and the protein content, which is slightly lower than average at 22 grams per serving. 

Finally, while this isn’t related to the protein itself, it’s worth calling out that Legion has fantastic customer service. You can chat with them at any time while browsing the website, and if you’re not happy, they’ll refund your order–you don’t even have to return the product. 

To learn more, check out our complete Legion Whey Protein Review.

Video Review

Best Sugar-Free Protein Powder for Weight Loss: Kaged Whey Protein Isolate

Good for: Those looking for a low-calorie protein for weight loss goals

Best For Weight Loss

Kaged Whey Protein Isolate

GGR Score: 4.5

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Product Highlights

• Whey protein isolate
• 25 grams of protein per serving
• Available in 3 flavors
• Third-party tested

Pros & Cons

Pros

• Affordable
• Good macro profile
• Reviewers claim it's easy on the stomach
• Tastes good
• Subscribe and save 10%
• Chocolate flavor described as the best chocolate protein powder by our product tester

Cons

• Clumpy when mixed
• Certain flavors out of stock frequently
• Only 3 flavors available

Bottom Line

Kaged Whey Protein Isolate is a fast-digesting protein available in five flavors with 25 grams of protein per serving.

If you’re losing weight and worried about losing muscle tissue along the way, studies show that adequate protein intake can help preserve muscle¹ in a calorie deficit, as well as reduce your appetite and help you stay full between meals.

Kaged Whey Protein Isolate uses high-quality ingredients, is gluten-free and non-GMO, and contains no artificial flavors. The macros vary slightly across flavors, but overall, this is one of the best protein powders for weight loss. The vanilla flavor packs in 25 grams of protein and only 100 calories per serving, which is notable. 

For those with sensitive stomachs who find that even whey isolates cause issues, Kaged has added prohydrolase, a digestive enzyme that helps break down and absorb the protein as quickly as possible.

The biggest callout is the solubility, which earned a 3.5-out-of-5 rating from GGR head of content and certified nutrition coach, Nicole Davis. She noted that the protein powder is a bit chunky with both cold water and milk, even when mixed in a shaker cup with a blender ball.

GGR collaborated with Ellipse Analytics, a third-party accredited lab that analyzed 150 protein powder samples to test for heavy metals, chemicals found in plastics, and label accuracy and purity. Kaged Whey Isolate met all standards and exceeded standards for pesticides and other harmful substances. Check out our Independent Supplement Testing Glossary for more information on how we tested these powders.

If you’re looking for a low-calorie, high-protein shake to help you reach your weight loss goals, without any added sugar, this is a great option that also has some of the lowest fat content we’ve seen in a protein powder. To read more, check out our complete Kaged Whey Protein Isolate Review.

Best Sugar-Free Protein Powder for Building Muscle: Ascent Whey Protein

Good for: Anyone looking to build muscle with a fast-digesting whey protein isolate

Best For Building Muscle

Ascent Whey Protein

GGR Score: 4.5

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Product Highlights

• Native whey protein blend
• 25 g of of protein per serving
• 6 flavor options
• 2- or 4-lb packaging
• Single serving packets available 
• Gluten-free
• Informed Sport Certified

Pros & Cons

Pros

• Native whey is the least-processed whey
• No artificial sweeteners or flavors
• Positive customer reviews

Cons

• Produced in a facility with tree nuts and peanuts
• Slightly pricey per serving

Bottom Line

Ascent Whey Protein offers a native protein blend, which the brand states is the least processed whey protein available on the market. This whey protein is also gluten-free and does not contain artificial ingredients. The brand offers six flavors (including an unflavored option). You can buy Accent whey in 2- or 4-pound bags or single-serving packets, which are available in 15-count increments.

For those looking to bulk up and build lean muscle tissue, the best protein powders for muscle gain will provide adequate protein without the excess sugar and calories that can easily lead to unwanted fat gain. Having some Ascent Whey Protein post-workout is a great choice for this goal. 

What makes it so special?

Well, for starters, Ascent uses a protein blend that contains native whey protein isolate, which they claim is the fastest-digesting whey protein available, along with regular whey isolate and whey protein concentrate. The difference between the three is small, but whey concentrate usually digests just a little bit slower than isolate, and research shows that whey concentrate may contain more biologically active components² that can support muscle growth. 

However, as Sydney Lappe, RD, pointed out in her Ascent Whey Protein Review, whey concentrate contains more fat and lactose than whey isolate and may cause digestive challenges for some users.

Kate Meier, NASM-CPT, USAW-L1, CF-L1, tested this protein and awarded it a 5-out-of-5 rating for both taste and solubility. She said it was somehow creamy, even with mixed with water, and was impressed that she couldn’t detect an aftertaste from the stevia at all. 

Each serving is also slightly higher in carbohydrates than many other options, and consuming carbs with your protein can reduce muscle damage³ after exercise. 

We also love that Ascent is Informed-Sport certified, which means it’s been tested for over 250 banned substances, making this a safe choice for athletes who undergo drug testing in their sport. Furthermore, a test by Ellipse Analytics, a third-party accredited lab that GGR collaborated with, found it exceeded standards for most harmful substances as well as label accuracy and purity. Check out our Independent Supplement Testing Glossary for more information on how we tested 150 protein powder samples.

Best Sugar-Free Protein Powder for Sensitive Stomachs: Dymatize ISO100

Good for: Anyone sensitive to lactose who wants an easily digestible protein

Best For Sensitive Stomachs

Dymatize ISO 100

GGR Score: 4.09

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Product Highlights

• Each serving contains 25 g of whey protein isolate 
• Pre-hydrolyzed protein to speed up absorption
• Available in 11 flavors, including Dunkin’ coffee flavors
• Low in both fat and carbohydrates

Pros & Cons

Pros

• 11 flavor options
• Includes 5.5 grams of BCAAs
• Fast absorption
• Flavors are highly rated

Cons

• Complaints of quantity in container
• Contains sucralose and stevia

Bottom Line

Available in 11 different flavors, Dymatize ISO100 is stacked with 25 grams of protein, including 5.5 grams of BCAAs and 4.4 grams of glutamine designed to enhance muscular growth and recovery.

For any protein enthusiasts out there who struggle with bloating after too many protein shakes, like myself, finding an option that’s both sugar-free and easy to digest is tremendously helpful, and Dymatize ISO100 is a great choice. 

Dymatize formulated this product with hydrolyzed whey, which is a type of protein that’s been processed even further for the fastest possible digestion. If you take whey isolate and pre-digest it with heat, enzymes, or acid, you’re left with the easiest possible protein to digest—hydrolyzed whey.

This results in a protein that’s very easy to digest, mixes well in liquids, and is extremely easy to digest. I’ve used ISO100 on and off for years and have tried six different flavors, all of which are delicious. However, our tester, Amanda Capritto, CPT, commented that the solubility is almost too good. She gave it a 4-out-of-5 score, saying that the texture is very thin, which is a bit strange with flavors like chocolate. 

GGR partnered with third-party accredited lab Ellipse Analytics to test 150 protein powder samples for harmful substances and label accuracy and purity. Dymatize ISO 100’s Gourmet Chocolate flavor met all standards explained in our Independent Supplement Testing Glossary, and ranked in the top 10% of its peers for label accuracy.

While the carb content ranges from 2-3 grams depending on the flavor, there are no added sugars in any of the flavors, even with delicious options like Fruity Pebbles, Cocoa Puffs, and Dunkin’ Glazed Donut. 

Those who are extremely sensitive to lactose may still need to find a different option, but for most people, this protein will digest perfectly fine without causing a stomach upset.

Read our Dymatize ISO100 review to see our full thoughts, or watch Lindsay’s video review below.

RELATED: Whey Protein Isolate vs Hydrolyzed Whey

Other Sugar-Free Proteins We Researched

We wanted to narrow down our list to eight protein powders so there are quite a few others that didn’t quite make the cut. 

Ghost Whey Protein: The Chips Ahoy protein is one of the best-tasting protein powders I’ve ever tried. However, several flavors do contain added sugar thanks to the pieces of Chips Ahoy, Oreos, and Nutter Butter. It’s a great protein, but we left it off because of this.

Transparent Labs Casein: While this formula scored a solid 4.18 in our Transparent Labs Casein review, casein protein is a slower-digesting protein that works well as a meal replacement or pre-bed snack, but many find the thick texture difficult to mix into smoothies or oatmeal. Even though whey and casein share a similar amino acid profile, we tip the scale slightly in favor of whey due to its versatility.

SEEQ Protein: This is a very popular clear whey protein, and we thought about adding it to our list. However, the protein content is on the low end compared to some of the other proteins, and as clear proteins often have strong fruit or berry flavors, they don’t have as much versatility. 

Truvani Plant-Based Protein: A lot of plant-based protein powders have a bit of a strange taste and texture, but this one does not. The ingredient profile is great, but the varying costs and higher carb content in many flavors kept it from making the list.

Optimum Nutrition Gold Standard Whey: This is a true classic in the protein world and one of the most popular protein powders around. However, we liked the ingredient profile and macros in the proteins we selected just a bit more, even though it’s still a great choice if you’re already a Gold Standard fan. 

How We Picked and Tested the Best Sugar-Free Protein

There’s no shortage of protein powders on the market, and it seems like every time I walk into my local health store, I see more brands I’ve never heard of. 

While we haven’t tested every protein powder just yet, our team of expert testers has personally tried over 115 protein powders and counting, carefully rating them according to our supplement testing methodology. Our testers have a variety of certifications and include registered dietitians, certified nutrition coaches, certified personal trainers, gym owners, and even an Olympian, so it’s safe to say that we understand how to rate protein powder. 

I considered collagen peptides, but they have different benefits and are typically better for joint health and anti-aging, rather than muscle building and repair. If you’re interested in reading more about collagen, we have a guide covering the benefits of collagen peptides.

Here are some of the most important factors we considered when assembling this list of the best sugar-free protein powders, which are useful things to consider when doing your own protein shopping. 

Sugar Content

The most important thing to consider is sugar, as sugar-free proteins should be mostly free of sugar. 

I say mostly because milk is rich in natural sugars, and while protein powders attempt to remove most of it, most proteins will have at least 1 gram of sugar from the protein itself. 

For this list, we specifically chose products with no added sugars, although some of the products may have small amounts of sugar for specific flavors, such as cookies and cream flavors that use bits of real cookies. If you’re in doubt, check the nutrition label first, and make sure there is no added sugar, or sugar in the ingredients list.

Protein Content

There’s no point in using a powder that doesn’t contain an adequate amount of protein, which supplies the essential amino acids your body needs to rebuild muscle. Protein content varies from brand to brand and can depend on the type of protein used, but we only award a 5-out-of-5 rating to products with at least 20 grams of protein per serving. 

For this specific list, we want to see at least 20 grams of protein, with minimal carbs, fats, and added sugars. Some of the products we chose may have certain flavor options with small amounts of sugar, but most flavors are sugar-free.

RELATED: How is Protein Powder Made?

Protein Source

There are several types of protein that can be used in protein powders. For a low-sugar protein, we generally look for whey proteins or whey isolates. While plant-based proteins can work well, they’re often higher in carbohydrates and may need extra sweeteners to make them taste good. Whey isolates are very low in carbs and can taste great even without sugar.

Price Per Serving

Price per serving is important, especially because protein isn’t exactly cheap. While we tried to be conscious of price, if a protein is expensive but well worth it according to our testing methodology, we feel comfortable recommending it. 

Though of course, if there’s an expensive product that doesn’t meet our standards, we’ll certainly avoid recommending it.

Solubility

Solubility refers to how well a protein powder mixes with liquid, a very important component if you’re going to be drinking a shake every day. After all, as GGR reviewer Lindsay Scheele said, there’s nothing worse than gagging on a weird, chunky protein ball that didn’t quite dissolve when you’re trying to enjoy a shake.

Taste

At the end of the day, the quality of the ingredients is the most important factor… but if the best sugar-free protein is something you dread every day, you’re never going to drink it. That’s why we carefully selected proteins that taste good, in addition to having quality ingredients. 

Third-Party Testing

Third-party testing is a great way to ensure the quality of your protein, verifying that each serving contains the ingredients it claims, and is free from harmful chemicals and ingredients. While we strongly recommend looking for products that use third-party testing, not all companies do this as the cost can be quite expensive.

If you don’t see third-party testing done on the protein powder you’re considering, the next best thing would be to look for a transparent label that clearly lists the exact amounts of each ingredient. 

Benefits of Sugar-Free Protein

If you’re wondering why you’d want to choose sugar-free protein, aside from the general idea that avoiding excess sugar is probably a good thing, there are a few additional benefits. I reached out to Destini Moody, RD, CSSD, LD, a sports nutrition expert and the head of performance nutrition for the NBA G League Ignite, to get her thoughts and recommendations. 

• Lower in calories: By replacing the sugar with artificial sweeteners, you’ll reduce the overall calorie intake, which can support weight loss goals.
• Keto-friendly: Because sugar-free proteins are very low in carbs, they work well for anyone following a ketogenic diet.
• Good replacement for certain whole foods: As Destini pointed out, whole food sources of protein, like cottage cheese, are often rich in natural milk sugars. Using a sugar-free alternative frees up some of those carbohydrates to use on other foods, like whole grains.
• Anti-inflammatory: While inflammation can have all sorts of causes, a 2022 study⁴ found that excessive sugar intake is associated with increased inflammation throughout the body, which may increase the risk of developing obesity, cardiovascular disease, and type 2 diabetes.

Potential Side Effects

As most of our selections use dairy-based protein, those with lactose intolerance may experience digestive problems when consuming these proteins. Whey isolates remove most of the lactose, and as someone with mild lactose intolerance myself, I can say that most whey isolates don’t cause any issues for me. However, some may need to avoid dairy entirely and choose a lactose-free option. 

While many experts agree that protein intake is both safe and beneficial for healthy adults, there can be some concern that too much protein intake may impact your kidneys, or cause side effects like bad breath, headaches, or constipation. 

RELATED: How Much Protein is Too Much?

I asked Destini Moody, RD, CSSD, LD if there were any issues with using artificial sweeteners like sucralose instead of regular sugar, as many are concerned about the regular consumption of these sweeteners. 

“Despite what the media says, RDs are not entirely convinced that artificial sweeteners are bad for your health,” Destini says. “That said, people should be wary of sugar alcohols in their protein powder and protein bars as these are low-calorie sweeteners that do not break down well in the gut and excess consumption can cause gas, stomach cramps, and diarrhea.” 

FAQs About Sugar-Free Protein Powder

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any diseases.

References

1. Leidy HJ, Clifton PM, Astrup A, et al. The role of protein in weight loss and maintenance. Am J Clin Nutr. 2015;101(6):1320S-1329S. doi:10.3945/ajcn.114.084038
2. Hoffman JR, Falvo MJ. Protein – Which is Best? J Sports Sci Med. 2004;3(3):118-130. Published 2004 Sep 1.
3. Liang Y, Chen Y, Yang F, et al. Effects of carbohydrate and protein supplement strategies on endurance capacity and muscle damage of endurance runners: A double blind, controlled crossover trial. J Int Soc Sports Nutr. 2022;19(1):623-637. Published 2022 Oct 12. doi:10.1080/15502783.2022.2131460
4. Ma X, Nan F, Liang H, et al. Excessive intake of sugar: An accomplice of inflammation. Front Immunol. 2022;13:988481. Published 2022 Aug 31. doi:10.3389/fimmu.2022.988481

Matt Dustin, CES, PN1-NC

Matt is a writer and fitness coach who's been working in the fitness industry for 11 years. Before joining the GGR team, Matt was a freelance health and fitness writer for 11 years, writing for dozens of fitness websites, influencers, and wellness brands. He's also the author of three nutrition books published through Simon & Schuster. He currently lives in Las Vegas, NV.

Further reading

Best Running Headphones in 2024: An Excellent Audio Experience That Stands Up To Intensity

by Lindsay Boyers, CN

Whether you’re looking for earbuds, an over-ear model, or something a little different, these are the best running headphones according to our testing. Read more

Best Time to Take Ashwagandha, According to a Registered Dietitian

by Alexandra Ginos, RD, MBA, CSP

Wondering when the best time to take ashwagandha is? Our registered dietician expert weighs in. Read more

How to Do a Seated Cable Row: Expert Tips and Mistakes to Avoid

by Kate Meier NASM-CPT, USAW-L1, CF-L1

Wondering how to do a seated cable row? Our in-depth guide provides cues and images of how to tackle this great upper-body exercise. Read more

Back Muscles Anatomy: Everything You Need to Know About Building Strong, Healthy Back Muscles

by Christopher Covello

What muscles make up your back? GGR’s Kate Meier covers back muscles anatomy, the best exercises for your back, and a killer back workout. Check it out! Read more