PETE NASTASI, CERTIFIED SPORTS NUTRITION COACH

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Our Top Picks for Best Whey Protein Powders in 2024:

Protein powder used to be fodder mainly for bodybuilders working to add muscle mass. My first exposure to whey protein was at a smoothie and supplement shop geared toward the type of people you see in physique contests—ripped and unnaturally tan wearing neon speedos or bikinis.

Since then, protein powder has gone mainstream, and the market options have exploded. In addition to standard whey protein concentrate, there are now whey isolates, casein, mass gainers and a variety of plant-based protein powders with protein sources as surprising as chia seeds and buckwheat, which are actually high in protein (1). (And here I thought plant-based milk manufacturers were grasping with pea milk.)

To help you make an informed decision, we’ve created this comprehensive guide to the best whey protein powders on the market in 2024. We consulted several registered dietitians and certified sports nutrition experts, and included our personal testing notes for each of the proteins on our list.

This content is meant to be informative, but should not be taken as medical advice. It is not intended for use as diagnosis, prevention or treatment of health problems. Always speak with your doctor before starting any new supplement or exercise regimen.

Why I picked it:

XWerks Grow 100% Grass-Fed Whey Protein Isolate is similar to Transparent Labs’ whey protein isolate because the foundation of both formulas is whey from 100 percent grass-fed cows. Supplement companies emphasize that their whey comes from 100 percent grass-fed cows usually because the cows are free to graze, and are thus less likely to need antibiotics from getting sick in crowded feedlots (4). XWerks Grow whey powder, like Transparent Labs whey powder, is sourced from cows free from antibiotics, hormones and pesticides. Both are also free of artificial flavors, colors and sweeteners.

So why did we choose XWerks Grow as the best whey protein powder? In addition to the purity of the formula, this protein is cold-pressed during processing, which purportedly preserves more of the protein and amino acids than processing with heat. It’s similar to how veggies like broccoli are considered more healthy when raw than cooked (5). 

Preserving the amino acids in your whey protein is important if you’re trying to build muscle. “Amino acids are important for many functions in the body, from building muscle to creating new immune cells,” says Maxine Smith, RD, LD of the Cleveland Clinic. “Whey protein contains branched-chain amino acids, a specific type of amino acid that helps with muscle building.”

It’s also delicious. Our testing team said it tasted the most like real chocolate out of all the protein powders we’ve tested. It’s made with real cocoa powder instead of chocolate flavoring, which gives it a much less artificial flavor than many protein supplements.

Testing scores:

What we love:

What to consider:

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Why I picked it:

If you’re interested in a low-calorie protein powder, chances are that you’re trying to cut fat without losing lean muscle mass. To ensure you’re getting enough protein without extra calories, a low-calorie protein powder supplement such as Legion Athletics Whey Protein can be useful.

“Protein powder can help with weight loss if you find eating enough protein difficult,” says Rachel MacPherson, CPT, CSCS and certified nutrition coach. “Protein is vital during weight loss diets because diets lower in calories than what you need to maintain your weight cause you to lose muscle as well as fat and other fat-free mass (such as water). To preserve muscle mass in a [caloric] deficit, increasing the ratio of protein in your diet is a very good idea.” (12)

Protein powders are generally low calorie, though some have a higher calorie count than others, depending on the protein source and additional ingredients. Whey isolate is the best form of protein for weight loss because it’s processed to reduce the fat and lactose content, leaving mainly high quality protein.

Legion Athletics Whey Protein has 100 calories and 22 grams of protein per serving from grass-fed cows on a small dairy farm in Ireland. It’s hard to find a protein powder with a lower calorie count and 22 grams of protein. For example, most of the protein powders we’ve tested have at least 120 calories per serving (though they typically have 24-25 grams of protein per serving). That’s one reason we chose Legion Athletic’s whey protein isolate as the best low-calorie protein powder.

We also chose it because it contains no artificial colors, sweeteners or flavors (it’s sweetened with stevia). Smith also says, “If you use a supplement, look for one that lists whey protein as the only ingredient,” and Legion Athletics Whey Isolate comes pretty close without skimping on flavor—the Chocolate Peanut Butter flavor is one of the best tasting protein powders I have ever tried.

Testing scores:

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Why I picked it:

Since protein supplements aren’t regulated by the FDA (6), quality and purity are vital when choosing the best protein powders. Some protein supplements can have filler ingredients or heavy metal contaminants that aren’t listed on the label (7).

Just like the name implies, Transparent Labs is a brand that works to put transparency and quality at the forefront of all its products. Each product is third-party tested for the presence of heavy metals and harmful bacteria, and you can find a certificate of analysis and certificate of composition (the percentage of each ingredient) on the Transparent Labs website. Having spent 10 years as a quality control chemist before becoming a sports nutrition coach, this commitment to transparency is exceptionally rare among supplement brands, and definitely factors into our team’s decision to name Transparent Labs 100% Grass-Fed Whey Protein Isolate as the best grass-fed whey protein powder.

This is one of my favorite whey protein powders for several reasons: the ingredients list is minimal (whey protein isolate, stevia, salt and organic or natural flavors), the whey isolate is sourced from 100 percent grass-fed cows, the per-serving protein content is excellent and it tastes amazing.

I recommend this protein powder as a post-workout muscle boost or a meal replacement shake to my clients. There are eight flavors to choose from, and my favorite flavor is the Chocolate Peanut Butter, with Oatmeal Chocolate Chip Cookie taking a close second.

Testing scores:

What we love:

What to consider:

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Why I picked it:

I’m lactose intolerant, and generally stick to plant-based protein powders, but if I opt for a whey powder, I use a whey protein isolate. Whey isolates like XWerks Grow are ultra-filtered to isolate only the highest quality whey protein. The filtration process removes unwanted carbs, fats and sugars (including lactose sugars), which makes whey isolate highly digestible for those with lactose intolerance.

It is also gluten-free, making it a stomach-friendly choice for those with gluten intolerance. I don’t feel comfortable recommending it to those with celiacs disease because, while XWerks says their whey protein is gluten-free, it doesn’t appear to be certified gluten-free. If this changes, I’ll update my recommendation.

Xwerks Grow is sweetened with stevia leaf extract. Unlike with sugar-free sweeteners such as erythritol, those who use stevia generally don’t report gastrointestinal issues like diarrhea or bloating (15). Grow does contain xanthan gum, which can cause gas and diarrhea at high levels (15 grams) (16), but you’re very unlikely to consume that much in a day, much less with one serving of this protein powder.

Overall, unless you’re allergic to dairy or have celiac disease, this protein powder is a creamy protein supplement that should digest easily without discomfort. I suggest mixing it with gluten-free oats, hot water, a spoonful of peanut butter and a few chocolate chips as a rich, tasty breakfast or mid-morning snack.

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What we love:

What to consider:

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Why I picked it:

Transparent Labs takes traditional chocolate protein powder and ups the ante with elevated flavor options like Milk Chocolate, Oatmeal Chocolate Chip Cookie, Chocolate Peanut Butter and Mocha for coffee lovers. I recommend this protein powder to my weight loss and personal training clients who have a sweet tooth because the flavors I’ve tried are delicious, and they’re sweetened with stevia and cocoa instead of sugar and artificial sweeteners or flavors.

Plus, this protein powder serves up so much more than a sweet treat. Each 34-gram scoop provides your muscles with 28 grams of grass-fed whey protein isolate and essential amino acids with minimal calories. The Chocolate Peanut Butter flavor is one of my absolute favorites. I mix it with water, but Transparent Labs and Gymshark athlete Diana Conforti bakes the Milk Chocolate flavor into chocolate chip peanut butter cookies for a protein-packed treat.

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How to Choose the Best Protein Powder for You

When looking for a protein supplement, think about more than just the amount of protein per serving. Also take into account the ingredient quality, macronutrient numbers, amino acid profile, taste and cost. It’s also good to look at manufacturing and third party testing. In most cases, supplements are not regulated by the FDA, so NSF Certified for Sport is the gold standard to look for. “Look for powders that have been third-party tested and ideally carry a certification like Informed Sport, Informed Sport, or NSF, which ensures that it’s not only safe, but that the label is accurate,” says Landes. And finally, consider what your goals are for supplementing with protein powders.

Here are a few common reasons people use protein powder and how to choose the right protein and dose for each of those goals:

Athletes who aren’t aiming to change their weight

Athletic performance-oriented individuals who aren’t concerned with gaining or losing weight can be fairly flexible with their protein powder choice. The main factor for them is choosing a protein that’s NSF Certified for Sport. They should also aim for the following daily protein intakes, expressed in grams of protein per pound (grams/pound) of body weight:

  1. Sedentary or low-intensity activity = 0.4 grams/pound
  2. Endurance Training (moderate/heavy training) = 0.5 to 0.7 grams/pound
  3. Strength & Power Training = 0.6 to 0.8 grams/pound

Muscle building/weight gain program

During a “bulking” phase, where you’re aiming to gain weight and build muscle, you are consuming excess calories and therefore have carbohydrates and fats to burn as fuel. This type of plan has a protein-sparing effect; because your body won’t need to use protein as energy, you won’t need to consume excess protein. The protein recommendations for a bulking program are 0.7 to one gram/pound of body weight (26). A protein powder with around 25 grams of protein per serving should work for this group.

Also, those on a muscle-building journey might also choose to supplement with creatine, one of the most well-researched supplements for improving muscle strength and growth. When simultaneously consuming a sufficient amount of protein and training properly, creatine can elevate your muscle stores by enhancing energy production (27).

Fat loss program

During a “cutting” phase, you are taking in less food (energy) than your body is burning, which places you in a caloric deficit to lose weight. While you are in a caloric deficit, you have less overall body fat and glycogen stores, which are the energy reserves for the body. In this scenario, your body is much more likely to break down muscle tissue as a source of energy since you are no longer getting energy from excess carbohydrates and fats (28). For this reason, you should increase your protein consumption. The protein recommendations are 0.8 to 1.2 grams/pound of body weight. As such, you should opt for a low calorie, high protein powder.

Body recomposition program

During this program you are looking to build muscle and lose fat at the same time. Although you might not see your overall weight change during this process, you should be able to see progress over time in the mirror. In this program, you’ll be using a maintenance level of calories (i.e., the number of calories your body needs in one day to stay at the same weight you are now) with the same protein requirement as a cutting phase (i.e. more protein).

Methodology: How We Chose the Best Protein Powders

As a certified sports nutrition coach and NASM certified personal trainer, I’m familiar with most of the protein powder formulations on the market. After personally testing 25+ protein powders and rating them out of five for mixability, texture, quality, protein per serving and third-party certifications, I compiled this list of the best protein powders based on each protein’s average score. The protein powders on this list are some of the highest scoring protein powders that I tested. Additionally, I referenced the expertise of dietitians and nutrition coaches such as Ellen Landes, MS, RDN, Emily Tills, RD and nutrition coach, and Rachel MacPherson, CPT, CSCS and certified nutrition coach.

Here’s a breakdown of what I look for when testing each protein powder. The scores are out of five, and then I calculate an average score across all five categories for the overall score.

Protein Powder FAQS

How much protein powder should I take in a day?

This depends on factors including your activity level, age and body weight. 50-60 grams of protein is what the average person should strive for in a day, sometimes more if you are working on building muscle or have different nutritional needs. According to the Mayo Clinic, excessive protein intake would exceed two grams per kilogram of body weight per day (29).

Are protein powder supplements regulated?

While the FDA doesn’t regulate any dietary supplements, there are companies that offer third-party testing. By looking for protein powder that’s Informed Sport certified or NSF Certified for Sport, you’ll ensure that what you see on the label is exactly what you get. This is even more important if you’re an athlete, as you’ll want to ensure there are no banned substances in your protein powder.

Is protein powder the same for men and women?

There is no difference between a protein powder for men and a protein powder for women. You may see protein powders recommended to either sex (we even have “best of” protein powder roundups for both men and women), but men and women process protein the same way.

The only case you could make for distinguishing between protein for men vs women is how much protein is recommended for each sex, though even those recommendations are based on generalized body types for men and women. “Men typically need a little bit more protein as they carry more muscle mass on their bodies,” says Emily Tills, a registered dietitian and nutrition coach. “Athletes are definitely going to need more, but also, that’s going to be dependent on the sport.”

Bottom line: Instead of choosing a protein powder based on your sex, look for protein that aligns with your dietary preferences, weight and fitness or health goals. When in doubt, talk with your healthcare provider or a registered dietitian.

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Expert Contributors

References

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  2. USDA. (2020). Dietary Guidelines for Americans 2020 -2025 (p. 97). https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf
  3. Kerksick, C. M., Wilborn, C. D., Roberts, M. D., Smith-Ryan, A., Kleiner, S. M., Jäger, R., Collins, R., Cooke, M., Davis, J. N., Galvan, E., Greenwood, M., Lowery, L. M., Wildman, R., Antonio, J., & Kreider, R. B. (2018). ISSN exercise & sports nutrition review update: research & recommendations. Journal of the International Society of Sports Nutrition, 15(1). https://doi.org/10.1186/s12970-018-0242-y
  4. Animals, N. R. C. (US) C. on D. U. in F. (1999). Approaches to Minimizing Antibiotic Use in Food-Animal Production. In www.ncbi.nlm.nih.gov. National Academies Press (US). https://www.ncbi.nlm.nih.gov/books/NBK232568/
  5. Van Eylen, D., Oey, I., Hendrickx, M., & Van Loey, A. (2007). Kinetics of the Stability of Broccoli (Brassica oleraceaCv. Italica) Myrosinase and Isothiocyanates in Broccoli Juice during Pressure/Temperature Treatments. Journal of Agricultural and Food Chemistry, 55(6), 2163–2170. https://doi.org/10.1021/jf062630b
  6. U.S. Food and Drug Administration. (2022, June 2). FDA 101: Dietary Supplements. U.S. Food and Drug Administration. https://www.fda.gov/consumers/consumer-updates/fda-101-dietary-supplements
  7. Bandara, S. B., Towle, K. M., & Monnot, A. D. (2020). A human health risk assessment of heavy metal ingestion among consumers of protein powder supplements. Toxicology Reports, 7, 1255–1262. https://doi.org/10.1016/j.toxrep.2020.08.001
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  9. de Azevedo Bittencourt, L. L., Pedrosa, C., de Sousa, V. P., Trindade Pierucci, A. P., & Citelli, M. (2013). Pea Protein Provides a Promising Matrix for Microencapsulating Iron. Plant Foods for Human Nutrition, 68(4), 333–339. https://doi.org/10.1007/s11130-013-0383-8
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  13. WHO advises not to use non-sugar sweeteners for weight control in newly released guideline. (2023, May 15). Www.who.int. https://www.who.int/news/item/15-05-2023-who-advises-not-to-use-non-sugar-sweeteners-for-weight-control-in-newly-released-guideline
  14. Is Sucralose (Splenda) Bad for You? (2021, January 12). Health Essentials from Cleveland Clinic. https://health.clevelandclinic.org/is-sucralose-splenda-bad-for-you/
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  16. Daly, J., Tomlin, J., & Read, N. W. (1993). The effect of feeding xanthan gum on colonic function in man: correlation with in vitro determinants of bacterial breakdown. British Journal of Nutrition, 69(3), 897–902. https://doi.org/10.1079/bjn19930089
  17. Stout, J. R., Smith-Ryan, A. E., Fukuda, D. H., Kendall, K. L., Moon, J. R., Hoffman, J. R., Wilson, J. M., Oliver, J. S., & Mustad, V. A. (2013). Effect of calcium β-hydroxy-β-methylbutyrate (CaHMB) with and without resistance training in men and women 65+yrs: a randomized, double-blind pilot trial. Experimental Gerontology, 48(11), 1303–1310. https://doi.org/10.1016/j.exger.2013.08.007
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  19. National Institutes of Health . (2020). Office of Dietary Supplements – Calcium. Nih.gov. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/
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  22. Proksch, E., Segger, D., Degwert, J., Schunck, M., Zague, V., & Oesser, S. (2014). Oral Supplementation of Specific Collagen Peptides Has Beneficial Effects on Human Skin Physiology: A Double-Blind, Placebo-Controlled Study. Skin Pharmacology and Physiology, 27(1), 47–55. https://doi.org/10.1159/000351376
  23. Khatri, M., Naughton, R. J., Clifford, T., Harper, L. D., & Corr, L. (2021). The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise: a systematic review. Amino Acids, 53(10), 1493–1506. https://doi.org/10.1007/s00726-021-03072-x
  24. Paul, C., Leser, S., & Oesser, S. (2019). Significant Amounts of Functional Collagen Peptides Can Be Incorporated in the Diet While Maintaining Indispensable Amino Acid Balance. Nutrients, 11(5), 1079. https://doi.org/10.3390/nu11051079
  25. León-López, A., Morales-Peñaloza, A., Martínez-Juárez, V. M., Vargas-Torres, A., Zeugolis, D. I., & Aguirre-Álvarez, G. (2019). Hydrolyzed Collagen—Sources and Applications. Molecules, 24(22), 4031. https://doi.org/10.3390/molecules24224031
  26. Iraki, J., Fitschen, P., Espinar, S., & Helms, E. (2019). Nutrition Recommendations for Bodybuilders in the Off-Season: A Narrative Review. Sports, 7(7), 154. https://doi.org/10.3390/sports7070154
  27. EARNEST, C. P., SNELL, P. G., RODRIGUEZ, R., ALMADA, A. L., & MITCHELL, T. L. (1995). The effect of creatine monohydrate ingestion on anaerobic power indices, muscular strength and body composition. Acta Physiologica Scandinavica, 153(2), 207–209. https://doi.org/10.1111/j.1748-1716.1995.tb09854.x
  28. Carbone, J. W., & Pasiakos, S. M. (2019). Dietary Protein and Muscle Mass: Translating Science to Application and Health Benefit. Nutrients, 11(5), 1136. https://doi.org/10.3390/nu11051136
  29. Wempen, K. (2016, November 21). Are you getting too much protein. Www.mayoclinichealthsystem.org. https://www.mayoclinichealthsystem.org/hometown-health/speaking-of-health/are-you-getting-too-much-protein

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.

Prices are accurate and items in stock at time of publishing.

Pete Nastasi, certified sports nutrition coach

BY PETE NASTASI, CERTIFIED SPORTS NUTRITION COACH

Pete Nastasi, the owner of Nastasi Nutrition, is a Certified Sports Nutrition Coach residing in North Carolina.