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The 10 best clean protein powders, reviewed by a dietitian

Slapping a “clean” badge of approval on a product may seem impressive, but what does it actually mean? By our standards, the term “clean” indicates there are minimal ingredients, zero artificial ingredients or sweeteners such as sucralose, and no fillers or thickeners like gums (with the exception of ready-to-drink shakes). This is especially important when it comes to the items you rely on for your health and wellbeing, like the best clean protein powder.

Protein comes from a variety of different animal and plant sources. If you want to lose fat but build muscle while intermittent fasting or calorie counting, whey protein isolate powder is the gold standard. If you’re following a gluten-free or vegan diet, or allergic to dairy, then plant protein may be a better choice.

To help you narrow down which is the best protein powder for you, our team tested dozens of options, evaluating them for price, ingredients, protein source, mixability, nutrition, taste, side effects and customer reviews.

Editor’s choice

The Transparent Labs 100% Grass-Fed Whey Protein Isolate offers a clean, protein-packed mix with less lactose and no sugar. This powder’s nutrient profile isn’t limited to just protein, either. It’s also rich in calcium, iron, and potassium, making it our team’s top pick for best clean protein powder.

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.

Our picks for the best clean protein powder

Compare clean protein powders

Transparent Labs Whey Protein Isolate Legion Casein+ Nutricost Organic Pea Protein Gainful Lose Weight Plant Based Protein Powder Transparent Labs Grass-Fed Protein+ Bars Sports Research Collagen Peptides Promix Nutrition Unflavored Vegan Protein Powder Naked Nutrition Goat Whey Protein Powder Orgain Keto Collagen Protein Powder Cymbiotika Plant Protein Vital Proteins Vital Performance Protein Powder Slate Milk High Protein Shake
Transparent Labs Whey Protein Isolate Legion Casein+ Nutricost Organic Pea Protein Gainful Lose Weight Plant Based Protein Powder Transparent Labs Grass-Fed Protein+ Bars Sports Research Collagen Peptides Promix Nutrition Unflavored Vegan Protein Powder Naked Nutrition Goat Whey Protein Powder Orgain Keto Collagen Protein Powder Cymbiotika Plant Protein Vital Proteins Vital Performance Protein Powder Slate Milk High Protein Shake
Rating
4/5
4.5/5
4.2/5
4/5
4.2/5
4/5
4.1/5
4/5
3.7/5
3.2/5
4.8/5
4.3/5
Servings 30 30 38 or 95 14 12 10-82 38 30 20 24 21 12
Cost per serving $2.00 $2.00 $0.47-$0.65 $3.21 $3.33 $0.87-$1.30 $1.04 $2.33 $2.10 $3.67 $1.43 $3.00
Flavor options 15 4 1 8 1 6 1 1 2 1 4 6
Protein source Whey protein isolate Casein Organic pea protein isolate Organic pea protein and organic brown rice protein Whey protein isolate Hydrolyzed bovine collagen peptides Organic Canadian yellow pea protein isolate Goat whey protein concentrate Bovine collagen Hemp, spirulina, and pea protein Bovine collagen and milk protein isolate Milk
Third-party tested Yes Yes Yes No N/A Yes Yes Yes No Yes Yes N/A

Best clean whey protein powder: Transparent Labs 100% Grass-Fed Whey Protein Isolate

a closeup of a person in a gym with their hand on top of a container of Transparent Labs's 100% Grass-Fed Whey Protein Isolate

Best clean whey protein powder

a closeup of a person in a gym with their hand on top of a container of Transparent Labs's 100% Grass-Fed Whey Protein Isolate
Each scoop of Transparent Labs Whey Protein Isolate contains 28 grams of protein and comes in a variety of flavors to choose from.
Fortune Score:
4 / 5

Key product features

FI Workout Type
High protein 28 grams
FI Third Party Testing
Sugar None added
FI Insurance Accepted
Fat Low
Fortune Icons
Flavors 15

What you should know

At 28 grams of protein per serving, the Transparent Labs Whey Protein Isolate provides the highest protein per serving on our list, with no additional additives or fillers.

  • Our testers found no issues with product mixing.
  • Each serving costs about $2, which is on the more expensive end of the market.
  • This protein powder is best for those focusing on building muscle, shedding fat, and post-workout recovery.
  • This whey protein isolate contains highly absorbable protein. ( 1 )
Pros
Third-party tested
Sourced from grass-fed cows
Available in 15 flavors
No artificial dyes or sweeteners
Gluten-free and non-GMO
Easy to mix
Cons
Higher price point than average
Not suitable for vegan or dairy-free diets
Some flavors are high in sodium

Why we like Transparent Labs 100% Grass-Fed Whey Protein Isolate as best whey

Transparent Labs Whey Protein Isolate is an easy win for best clean whey protein powder. It’s made from whey protein isolate, a type of protein sourced from cow’s milk that boasts benefits like muscle mass gains and muscle recovery.

Whey protein isolate is a product of minimizing fat and carbohydrate, namely lactose, and is a highly concentrated source of protein. ( 2 ) Compared to casein, a different type of milk protein, whey is slightly higher in one of the three branched-chain amino acids (BCAA), called leucine, which may give it a leg up on muscle-building potential. ( 3 )

“Leucine is a critical component in the process of protein synthesis, which is ultimately necessary for gaining muscle.”

Chris Mohr, Ph.D., RD, Fortune Recommends Advisor

The price of this Transparent Labs protein powder is right around average at $2 per serving, and you truly get what you pay for. We like that the ingredient list is a simple read and that it’s free of many ingredients found in other nutritional supplements like sucralose, aspartame, and fillers.

Aside from being easy to mix into beverages, we love the diverse array of flavors Transparent Labs offers, from blueberry pancake to chocolate peanut butter. Our testers personally couldn’t get enough of the peppermint hot chocolate flavor and are convinced that adding whipped cream and marshmallows would transform your post-workout drink into something truly delicious. The brand also offers an unflavored option that can take on the flavor of whatever you add to it and is soluble in virtually anything.

It’s worth noting that sodium levels are generally higher per serving with this protein powder than others on the market, but opting for the unflavored or vanilla options will help keep sodium levels down if that’s a concern.

We also appreciate that Transparent Labs makes their purity and composition third-party testing visible to the customer and potential customers right on their website, so you know you can trust the contents of what you’re buying.

“The Transparent Labs Whey Protein is Informed Choice Certified, which is an important standard, to know that what’s on the label is in the product—and nothing more,” says Chris Mohr, Ph.D., RD.

What customers are saying

Transparent Labs Whey Protein Isolate has 160 reviews on Amazon, with customers noting great taste and a trusted ingredient list as reasons for liking the product.

“It tastes delicious, has no sugar, mixes perfectly, perfect for keto,” Jeannette C wrote. “I blend it with water real quick in my little Ninja Bullet, and it’s like a milkshake. Delicious!”

“A little more expensive than standard off the shelf proteins, simply based on volume, but the effort and intentionality that goes into producing such a clean and nutritionally rich protein, you’re definitely getting more bang for your buck with this product.”

Nancy S., verified Amazon customer

Solubility—how easy the powder dissolved in water—also earned high praise from reviewers.

“Fantastic product! It tastes great and it blended really well in my shakes,” wrote Caleb H. “It’s my new favorite protein powder.”

What our lab analysis showed

Our third-party lab analysis showed Transparent Labs Whey Protein Isolate did not contain unsafe levels of heavy metals, bisphenols, phthalates, or pesticides.

Specs

Rating 4/5
Third-party testing Yes
Servings 30
Cost per serving $2.00
Protein type Whey protein isolate
Protein per serving 28 grams
Calories per serving 120–150
Carbohydrates per serving 0–3 grams
Fat per serving 0.5–2.5 grams

Best clean casein protein powder: Legion Casein+

a close-up of a blue and black bag of Legion Athletics's Casein+ protein powder, dutch chocolate flavor, against a bright blue background

Best Clean Casein Protein Powder

a close-up of a blue and black bag of Legion Athletics's Casein+ protein powder, dutch chocolate flavor, against a bright blue background
The brand offers 24–26 grams of casein protein and minimal ingredients, meeting our standards for “clean.”
Fortune Score:
4.5 / 5

Key product features

FI Workout Type
High protein 24–26 grams
FI Third Party Testing
Sugar None added
FI Insurance Accepted
Fat Low
Fortune Icons
Flavors 4

What you should know

The Legion Casein+ nutrition label provides one of the highest grams of protein per serving we reviewed, from ingredients we trust.

  • Casein is thick in texture and may take extra effort (or liquid) to mix.
  • At about $2.00 per serving, Legion’s Casein+ protein powder costs right around average compared to others on the market.
  • Might be a good choice for those who workout in the evenings, since data suggests a serving of casein protein in the evening may help with recovery and growth. ( 4 )
  • Legion Athletics offers great customer service and refund policies.
Pros
Third-party tested
No artificial dyes or sweeteners
Gluten-free and non-GMO
Made with high-quality casein protein
Offers 50–60% of the daily value of calcium per serving
NSF-certified for Sport (no banned substances)
Cons
May be hard to mix on the go
Only available in four flavors
Not suitable for vegan or dairy-free diets
Higher price point per serving than average

Why we like Legion Casein+ as best casein

Legion Casein+ is our pick for best casein protein because it delivers 24 to 26 grams of protein in each serving while remaining a low 110 calories, depending on what flavor you choose. This sets it apart from other casein proteins that are higher in calories and provide less protein. Legion Casein+ sources micellar casein, high-quality casein, from Irish dairy cows. Because of its high-quality ingredient list, Casein+ has a higher price point of about $2 per serving.

Casein can take longer to digest than other forms of protein, like whey. This could be a positive thing for people who like to train into the evening—a slower digestion of protein may help promote muscle growth even while you sleep. ( 4 )

“As a dietitian who works with a variety of athletes, I love the utility of casein protein, particularly for those who are training hard, often multiple hours each day. The data suggesting it could make for an effective evening snack is one most athletes can get behind.”

Chris Mohr, Ph.D., RD, Fortune Recommends Advisor

Casein is a complete protein, meaning it contains all essential amino acids necessary for protein synthesis and recovery. ( 5 ) Each scoop of Legion’s Casein+ also packs 50% to 60% of the daily value for calcium, one of four critical nutrients many Americans are lacking .

“While more research is necessary, studies have shown that casein protein can cause gastrointestinal distress in certain individuals. Particularly, if you are lactose intolerant, this may not be a good option for you,” says Jen Roper, Ph.D., CSCS, an associate professor of health and human sciences at Loyola Marymount University. ( 6 )

Casein protein powder tends to be thick in texture, and our testers found that it took a little more effort to blend it smoothly into shakes. Relying on a blender ball may not be enough for this protein powder. But, because it’s thicker, it may leave you feeling more satisfied, which may come in handy when post-workout hunger strikes. Therefore, we still gave it a high score for mixability, since it does mix well with the added effort.

Though free of added sugars, the four Legion Casein+ flavors are still pleasantly sweet thanks to monk fruit, stevia, and/or erythritol. Our testers tasted the banana cream pie flavor, a popular choice with a rich, creamy texture and subtle banana taste.

Legion claims to have all products analyzed through third-party testing to make sure you’re getting a pure, honest product; however, we couldn’t verify this for their Casein+ powder. We like that Legion has a “no returns necessary policy” where you can get a full refund without having to return the protein powder. But, we didn’t like navigating their website, which bombards you with ads and email forms.

What customers are saying

The Legion Casein+ has 1,020 reviews on Amazon, with reviewers noting how nicely the powder blends into beverages.

“Really loved this Casein+. Mixes superbly and doesn’t have that chalky unpleasant texture that some casein does,” verified customer Alex wrote.

“This product blended well—1 scoop to 10 oz of water—and the flavor crew at Legion deserve major props. Tastes EXACTLY like cinnamon toast crunch the kids cereal… I will gladly drink this nightly as a bedtime shake!!”

Alan C., Amazon

Several reviewers, on the other hand, pointed out that they didn’t feel well after consuming the product.
“This product made my stomach hurt and wreaked havoc on my digestion,” Elyssa wrote.

What our lab analysis showed

Our third-party lab analysis showed that Legion Casein+ did not contain unsafe levels of heavy metals, bisphenols, phthalates, or pesticides.

Specs

Rating 4.5/5
Third-party testing Yes
Servings 30
Cost per serving $2.00
Protein type Casein
Protein per serving 24–26 grams
Calories per serving 110–140
Carbohydrates per serving 2–5 grams
Fat per serving 0–2 gram

Best clean organic protein powder: Nutricost Organic Pea Protein

Nutricost Organic Pea Protein Powder container

Best Clean Organic Protein Powder

Nutricost Organic Pea Protein Powder container
Nutricost Organic Pea Protein offers 20 grams of protein from organic yellow split peas and serves as a good source of iron.
Fortune Score:
4.2 / 5

Key product features

FI Third Party Testing icon
Flavors Unflavored
FI Warranty icon
Iron 35% daily value per serving
FI Best Of icon
Protein 20 grams per serving
FI Diet Type icon
Calories Under 100

What you should know

Nutricost Organic Pea Protein contains 20 grams of protein and absolutely no additives. Here’s what else you should know before purchasing it.

  • This product only comes in an unflavored option, meaning you can easily mix it with whichever beverage you’d like.
  • You’ll spend only $0.47 to $0.65 per serving, depending on the size of the container purchased, making it the most affordable protein powder featured here.
  • This is a great option for those following a vegan diet or those with an allergy or intolerance to dairy, soy, or egg.
Pros
Made in a GMP-compliant facility to ensure quality
No artificial ingredients
Very affordable
Certified organic
Third-party tested
Cons
Only comes unflavored
Higher in sodium than other options
Not suitable as a primary protein source

Why we like Nutricost Organic Pea Protein as best organic

Nutricost Organic Pea Protein is our pick for the best clean organic protein powder, providing 20 grams of protein and 90 calories per serving, with zero additives. This unflavored formula contains just a single ingredient: organic pea protein isolate.

For protein powders, pea protein typically comes in two forms—concentrate and isolate. Pea protein isolate, found in Nutricost’s formula here, is derived from yellow split peas. It contains less carbohydrates and has a higher protein content (by weight) than its concentrate counterpart. ( 7 ) The protein digestibility of pea protein isolate is also higher than other plant-based proteins and on par with that of casein, meaning it has a high nutritional quality. ( 8 )

Pea protein contains all nine essential amino acids, which play a key role in protein synthesis in the body. ( 9 ) But it’s low in methionine, which helps with digestion function and reducing DNA damage, among other benefits—so it shouldn’t be relied on as a primary protein source. ( 10 ) Pea protein is also high in branched-chain amino acids (BCAAs), which help maintain and grow muscles. ( 27 )

Nutricost Organic Pea Protein is a good source of iron, containing 30% of the daily value per serving, which helps store oxygen in muscle cells, helps transport oxygen throughout the bloodstream, and is important to the overall function of organs. ( 11 , 18 ) Plus, it provides 6% of the daily value for calcium per serving, which, along with contributing to bone health, helps muscles contract.

The sodium levels of this formula are a bit higher than average for a protein powder though, with 220 milligrams or 10% of the daily value per serving, which may not be suitable for those following a low-sodium diet.

This product is only available in an unflavored option, but that means it can be easily mixed into any beverage of choice.

This vegan and non-GMO protein powder is made in a GMP-compliant facility, meaning that the manufacturing process follows the regulations set by the FDA to ensure a high quality, pure product.

It’s worth noting that the iron, sodium, calcium, potassium, fiber, and overall calorie content as listed on each nutrition label varies slightly by container size for the unflavored option. But the protein content for each is still 20 grams per serving.

What customers are saying

Nutricost Organic Pea Protein has over 700 reviews on Amazon. Most customers appreciate the affordability and high quality of the product, but think it needs to be mixed with other ingredients to improve its flavor.

“If you are in the market for unflavored vegan protein, this product is great also because it’s 1) affordable and 2) organic. I love that it comes in a 5 lb tub and lasts for months!” wrote a verified Amazon customer named Phileo.

“This protein powder blends great with no aftertaste or grittiness. I make a protein shake every morning with this, almond milk, frozen strawberries and bananas. Sometimes I switch up the fruit for a different flavor. It’s half the cost of the pea protein powder I was using,” wrote an anonymous Amazon customer.

Reviews were mixed on the product’s taste and blendability.

“It is very very blah in taste, however, I make my smoothies with it and add different fruits and/or peanut butter. It’s a great smoothie for when on the go or road. It has more texture than your average protein powder and is very filling. I’ll definitely get it again. If you want flavor you have to add it, that’s for sure!” wrote a verified Amazon customer with the username Flomango.

Specs

Rating 4.2/5
Third-party testing Yes
Servings 38 or 95
Cost per serving $0.47 or $0.65
Protein type Organic pea protein isolate
Protein per serving 20 grams
Calories per serving 90-100
Carbohydrates per serving 1 gram
Fat per serving 1.5-2 grams

Best clean protein powder for weight loss: Gainful Lose Weight Plant Based Protein Powder

Customizable Gainful Protein Powder

Best Clean Protein Powder for Weight Loss

Customizable Gainful Protein Powder
Gainful Lose Weight Plant Based Protein Powder is a great all-natural option designed to promote satiety and weight loss.
Fortune Score:
4 / 5

Key product features

FI Third Party Testing icon
Flavors 8 flavor “boosts”
FI Warranty icon
Protein 24 grams
FI Veteran Discount icon
Carbs 2 grams per serving
FI Diet Type icon
Calories 120

What you should know

Gainful Lose Weight Plant Based Protein Powder is a natural, unflavored option with a high-protein, low-carb formula oriented to helping promote weight loss.

  • This product comes unflavored, but you can choose to add one of eight flavor “boosts”—two of which come with your purchase.
  • Gainful Protein Powder costs above average, at $3.21 per serving, and only contains 14 servings total.
  • Our testers enjoyed the taste and liked that they could customize the flavor, though they noted the powder didn’t blend well in a shaker bottle.
Pros
Only contains natural ingredients
Combining pea and rice protein provides a more complete plant-based protein source
Flavor boosts taste good according to our testers
Comes with access to registered dietitians
Cons
Not third-party tested
Your purchase only comes with two flavor boost packets, despite containing 14 servings
Costs much higher than average at $3.21 per serving
Doesn’t blend well in a shaker bottle

Why we like Gainful Lose Weight Plant Based Protein Powder as best for weight loss

Gainful’s Lose Weight Plant Based Protein Powder option is our pick for the best clean protein powder for weight loss because of its high-protein, low-fat, and low-carb formula that doesn’t contain any artificial additives.

This formula contains 24 grams of protein per serving, which comes from organic pea protein and organic brown rice protein. There is also only 1.5 grams of fat and 2 grams of carbohydrates per serving, plus 1 gram of fiber.

As discussed with Nutricost’s Organic Pea Protein above, pea protein contains all essential amino acids (EAAs) and is especially high in lysine, though it’s low in methionine. Rice protein, on the other hand, is low in lysine but high in methionine. ( 12 ) So, the two protein sources complement each other well. Gainful’s protein powder formula here is a more complete and balanced source of protein (and all EAAs) than other plant-based options.

One study comparing the effectiveness of rice protein versus whey protein supplementation in men over eight weeks of resistance training found there were similar changes in both body composition and performance—with both a 24-gram dose and 48-gram dose. ( 13 )

Gainful’s Lose Weight Plant Based formula is a good source of iron, providing 3.3 milligrams or 20% of the daily value per serving. It also provides 20% of the daily value of phosphorus (250mg), 6% of the daily value of calcium (80mg), and 2% of the daily value of potassium (60mg).

This formula also contains green tea extract, though it doesn’t specify how much. One study conducted on 115 women found that a daily high dose (856.8 mg) of green tea extract over 12 weeks resulted in weight loss (approximately 2.4 pounds) as well as a decrease in total cholesterol. ( 14 )

Though it comes unflavored, there are currently eight “flavor boost” options that are naturally sweetened with stevia extract and monk fruit extract: strawberry cream, Madagascar vanilla, rich chocolate, caffe mocha, cookies & cream, chocolate peanut butter, cinnamon toast, and sea salt caramel.  Depending on which flavor you choose, a single flavor boost packet will add another five to 10 calories from carbohydrates.

Our testers enjoyed the different flavors and being able to customize the taste of the protein powder. But they noted the powder doesn’t blend well in a shaker bottle and remains clumpy.

Though Gainful advertises their commitment to using “clean” ingredients, their protein powder does not seem to be third-party tested or made in a GMP-compliant facility.

Purchasing this product will also give you access to Gainful’s team of registered dietitians.

Specs

Rating 4.5/5
Third-party testing No
Servings 14
Cost per serving $3.21
Protein type Organic pea protein and organic brown rice protein
Protein per serving 24 grams
Calories per serving 120
Carbohydrates per serving 2 grams
Fat per serving 1.5 grams

Best clean protein bar: Transparent Labs Grass-Fed Protein+ Bars

a closeup of Transparent Labs's Grass-Fed Protein+ peanut butter chocolate chip-flavored protein bar in its wrapper

Best Clean Protein Bar

a closeup of Transparent Labs's Grass-Fed Protein+ peanut butter chocolate chip-flavored protein bar in its wrapper
Transparent Labs’s Grass-Fed Protein+ Bars contain 15 grams of protein and are free of artificial sweeteners, coloring, and preservatives
Fortune Score:
4.2 / 5

Key product features

FI Third Party Testing
Sugar No artificial sweeteners
FI Serving Size
Ingredients Whole foods
FI Shipping Mattress
Subscription Available

What you should know

At 15 grams of protein per bar, the Transparent Labs Grass-Fed Protein+ Bars are a high-quality, on-the-go protein boost.

  • At $3.33 a bar, this is a more expensive protein option than many others on the market.
  • This is a great option for people who are looking for an alternative to traditional protein powder.
  • Contains 3 grams of filling fiber for a satisfying snack.
Pros
Made with high-quality whey protein isolate
Portable
Great taste and texture
Good source of fiber
Contains real ingredients
Cons
Higher price point per serving than average
High in sodium and saturated fat
Only one flavor option
Not suitable for vegan, peanut-free, egg-free, or dairy-free diets

Why we like Transparent Labs Grass-Fed Protein+ Bars as best protein bars

Protein bars like Transparent Labs’s Grass-Fed Protein+ Bars can be a convenient alternative to blending shakes, making increasing your protein intake easier by taking it on-the-go. But this convenience does come at a higher price point. The brand sells its only flavor, peanut butter chocolate chip, in a 12-pack, which comes to $3.33 per bar.

You’ll find that Transparent Labs sticks to providing high-quality protein from grass-fed cattle, offering an impressive amino acid profile that complements fitness and overall wellness. Unlike protein bars made with refined sugars and natural flavors, these bars utilize naturally sweet ingredients like tapioca syrup (from cassava root), honey, and dates. We like that Transparent Labs remains transparent, and explains every ingredient for the bars on their website.

Our testers noted that the bars have a defined peanut butter and chocolate taste, with real pieces of chocolate that melt in your mouth. If you find it hard to stomach protein bars, consider still giving these a try. Unlike other protein bar brands, this one doesn’t have the typically chalky textures and super sweet aftertaste, while also providing a soft and chewy texture with some dryness.

If you’re keeping careful watch of your macros, it’s important to know that every bar has 16 grams of fat, 23 grams of carbohydrates, and 15 grams of protein. Additionally, there’s also 3 grams of fiber, which may support gut health. ( 15 )

“Fiber has been called a ‘nutrient of concern’ since most Americans aren’t eating enough of this important nutrient. Fiber supports heart health, gut health, and just wellbeing as a whole.”

Chris Mohr, Ph.D., RD, Fortune Recommends Advisor

For those following a heart-healthy diet, the protein bars have 25% of the daily value of saturated fat, which the American Heart Association advises reducing to protect heart health. ( 16 ) Moreover, they’re higher in sodium, at 12% of your daily value per bar. Neither of those make it a bar that’s “off limits,” but rather a reminder that these should be used as a complement to a diet balanced with plenty of variety and nutrition, instead of a regular staple.

These bars also aren’t free of several common allergens and are not fit for people allergic to peanuts, eggs, or dairy.

Specs

Rating 4.2/5
Third-party testing N/A
Servings 12
Cost per serving $3.33
Protein type Whey protein isolate
Protein per serving 15 grams
Calories per serving 280
Carbohydrates per serving 23 grams
Fat per serving 16 grams

Best clean collagen protein powder: Sports Research Collagen Peptides

Container of Sports Research Collagen Peptides

Best Clean Collagen Protein Powder

Container of Sports Research Collagen Peptides
Sports Research Collagen Peptides contains 11 grams of hydrolyzed bovine collagen peptides and is third-party tested.
Fortune Score:
4 / 5

Key product features

FI Third Party Testing icon
Flavors Unflavored
FI Resistance levels icon
Sizes 7 options
FI Best Of icon
Collagen 11 grams per serving
FI Diet Type icon
Calories Low

What you should know

Sports Research Collagen Peptides contains 10 grams of protein and only one ingredient: hydrolyzed bovine collagen peptides. Here’s what else you should know before purchasing it.

  • This product only comes in an unflavored option, meaning you can easily mix it with whichever beverage you’d like.
  • You’ll spend less per serving than average, from $0.87 to $1.30, but you’ll also get a lower amount of protein.
  • May be good for those who are endurance athletes or experience joint pain.
Pros
No artificial ingredients
Easy to mix
Available in many sizes
Informed Choice Certified
NSF Certified gluten-free
Cons
Not suitable for vegan or dairy-free diets
Sizes and availability vary by flavor
May not be enough protein for some

Why we like Sports Research Collagen Peptides as best collagen

Sports Research Collagen Peptides is our pick for the best clean collagen protein powder, providing 10 grams of protein and 40 calories per serving. It has zero artificial additives. While many protein powders on the market have a laundry list of ingredients, this formula only contains cow-derived hydrolyzed collagen peptides, natural flavors, and natural sweeteners.

Collagen is a connective tissue protein and is the most abundant protein in the body. It is a structural protein, providing strength and integrity for healthy bones, tendons, and cartilage. A large 2021 review of research studies found that supplementing with collagen may improve muscle recovery and body composition, and reduce joint pain and enhance joint function, but didn’t support muscle protein synthesis. ( 17 )

The sodium levels in this formula are minimal, at 3% daily value per serving, which may be helpful for those following a low-sodium diet. Our reviewers also noted how smooth this protein powder is.

Sports Research Collagen Peptides is available in a variety of sizes including 10, 20, 24, 30, 40, 41, or 82 servings, depending on the flavor selected. There are currently six flavor options: unflavored, dark chocolate, matcha green tea, vanilla, organic chocolate, and organic unflavored.

This product is NSF Certified gluten-free, meaning it’s tested and verified to be gluten-free. It’s also Informed Choice Certified, which means it’s tested for banned substances, ensuring you’re getting a safe product that meets label claims.

What customers are saying

Sports Research Collagen Peptides has over 131,000 reviews on Amazon, and the large majority are positive. Most customers like the product for its ease of solubility, enjoyable taste, simple ingredients, and support in injury recovery and other conditions.

“For cost, convenience, flavor, and effectiveness, this is [the] best collagen product I’ve tried overall.”

Rocky S., Amazon customer

“I have enjoyed my daily coffee with 1-2 scoops of Collagen Peptides for 3 years. It dissolves quickly and has almost no flavor (as expected). It also does not add any bulk to my coffee texture but has given me some amazing benefits,” wrote verified Amazon customer Brian Ammon.

Specs

Rating 4/5
Third-party testing Yes
Servings 10-82
Cost per serving $0.87-$1.30
Protein type Bovine collagen
Protein per serving 10 grams
Calories per serving 40
Carbohydrates per serving 0 grams
Fat per serving 0 grams

Best clean vegan protein powder: Promix Nutrition Unflavored Vegan Protein Powder

Bag of Promix Nutrition Unflavored Vegan Protein Powder

Best Clean Vegan Protein Powder

Bag of Promix Nutrition Unflavored Vegan Protein Powder
Promix Nutrition Unflavored Vegan Protein Powder has 25 grams of pea protein, plus vitamin B12.
Fortune Score:
4.1 / 5

Key product features

FI Key Ingridient icon
Ingredients Plant-based
FI Best Of icon
High protein 25 grams per serving
FI Warranty icon
Third-party tested Yes
FI Third Party Testing icon
Flavors 1

What you should know

Completely free of additives, Orgain Keto Collagen Protein Powder supplies 10 grams of protein in each 90-calorie scoop.

  • This is an excellent option for people following a keto diet.
  • At $2.10 per serving, this costs slightly above average compared to other protein powders on the market.
  • It’s naturally sweetened with stevia extract.
Pros
Third-party tested
USDA organic
No artificial sweeteners, colors, or flavors
Easy to mix and digest
Suitable for a wide-range of special diets
Iron-rich
Cons
Pea protein powders are low in methionine
Unflavored option may taste bad to some

Why we like Promix Nutrition Unflavored Vegan Protein Powder as best vegan

Some research reports a higher prevalence of iron and vitamin B12 deficiency among people who are vegetarian or vegan. ( 18 , 19 )  Our top pick for best clean vegan protein powder, Promix Nutrition Unflavored Vegan Protein Powder is a helpful tool for vegans to add not only protein but also iron and vitamin B12 to their diet, to limit their risk of deficiency or insufficiency.

This vegan protein powder contains 25 grams of protein from Canadian yellow peas, no fat, and 2 grams of carbohydrates. It’s a good source of iron, too, and provides 23% of the daily value per serving. It also provides 10% of the daily value of calcium and 3% of the daily value of potassium per serving.

Plus, Promix has added in vitamin B12, which is readily found in many animal products and may need to be supplemented by those following a vegan diet. ( 19 )

“Research has shown that those who do not eat animal protein may have higher protein needs than those who do, to ensure all essential amino acid needs are met. ( 20 ) Adding in a quality vegan protein powder, such as this, offers the ability to increase protein intake in a simple, yet effective, manner,” says Mohr.

If you’re seeking a product that offers a complete protein, you’ve found it. Promix’s formula supplies all essential amino acids, which are key to synthesizing protein in the body, as well as 5.2 grams of branched-chain amino acids, which may help with muscle recovery and growth. ( 9 , 27 ) However, pea protein is low in methionine and should not be used as a primary protein source.

“It’s important to note that consumption of amino acid supplements can have some side effects. Bloating, nausea, diarrhea, etc. have often been reported with supplements, likely due to the lactose content. This protein could be beneficial for those who are sensitive to other products on the market,” says Roper, Ph.D., CSCS, an associate professor of Health and Human Sciences at Loyola Marymount University. ( 21 )

While this protein powder also comes in raw chocolate and french vanilla flavors, we think the  unflavored option is the cleanest and least likely to be contaminated with heavy metals. But we like that Promix does go the extra mile and provides the data results from third-party testing for their products right on their website.

If you follow a low-sodium diet, it’s worth noting that this pea protein powder has half the amount of sodium of Nutricost’s Organic Pea Protein, listed above.

What customers are saying

Promix Nutrition Vegan Protein Powder has over 850 reviews on Amazon. Many customers like the quality of the protein powder, how well it mixes, and how it doesn’t result in bloating like some other options.

“Many protein powders on the market contain detrimental ingredients. When I saw this product and its ingredients, I was excited about how ‘clean’ it was. When I had my first smoothie with it, my digestive system agreed and it felt ‘pure.’ The taste is mild, but my body simply feels clean with it, rather than all the bloating from traditional protein powders,” wrote verified Amazon customer Kyle.

Unsavory reviews were rare, however, they were related to taste and texture.

“I have never had unflavored vegan protein powder, so I am not sure how this compares to others, but I did not enjoy the taste of this product.”

Anna, verified Amazon customer

Specs

Rating 4.1/5
Third-party testing Yes
Servings 38
Cost per serving $1.04
Protein type Pea protein isolate
Protein per serving 25 grams
Calories per serving 115
Carbohydrates per serving 2 grams
Fat per serving 0 grams

Best clean goat protein powder: Naked Nutrition Goat Protein

a close-up of Naked Nutrition's Naked Goat 100% premium grass-fed goat whey protein powder

Best Clean Goat Protein Powder

a close-up of Naked Nutrition's Naked Goat 100% premium grass-fed goat whey protein powder
This protein powder’s single ingredient—goat whey protein concentrate—makes it a simple, clean protein option.
Fortune Score:
4 / 5

Key product features

FI Workout Type
High protein 23 grams per serving
Fortune Icons
Flavor Unflavored
FI Diet Type
Fat Low
FI Insurance Accepted
Carbs Low
FI Shipping Mattress
Subscription Available

What you should know

Naked Nutrition Goat Whey Protein Powder is comparable to whey protein isolate, with 23 grams of protein per serving.

  • At about $2.33 per serving, this is more expensive than average.
  • Great option for those with a mild lactose sensitivity.
  • Sourced from grass-fed Wisconsin cattle.
Pros
Versatile
Low lactose
High-quality protein with BCAAs
No artificial ingredients
Certified gluten-free
Responsive customer service
Cons
Refunds only on unused items
Not suitable for vegan or dairy-free diets
More expensive than average

Why we like Naked Nutrition Goat Whey Protein Powder as best goat protein

Naked Nutrition Goat Whey Protein Powder steals the top spot for best clean goat protein powder with its one ingredient formula—goat whey concentrate. Whey concentrate undergoes less processing than whey protein isolate. “This doesn’t make whey protein concentrate ‘bad’ per se, but whey concentrate is generally higher in lactose and fat compared to whey isolate,” says Mohr.

Milk coming from a cow or goat is generally the same nutritionally, but some research suggests goat milk is more easily digestible, which could be important for those who may not tolerate dairy protein from cow milk. ( 22 )

Naked Nutrition’s product also impressed us with its nutrient profile, which is comparable to whey protein isolate. Each two scoop serving provides 110 calories, 2 grams of carbohydrates, 0.5 grams of fat, and 23 grams of protein.

Similar to other whey protein powders, Naked Nutrition is a complete protein, providing all essential amino acids (EAAs) including branched-chain amino acids (BCAAs), which may reduce muscle soreness after weight lifting, particularly if overall protein intake isn’t optimal. ( 23 )

“While BCAAs are important, they aren’t necessary in a diet that already provides adequate quantities and quality of protein. More isn’t necessarily better, unless protein intake is inadequate and needs aren’t being met.”

Chris Mohr, Ph.D., RD, Fortune Recommends Advisor

Naked Nutrition Goat Protein is also third-party tested and prides itself on having “nothing to hide.” We like that it’s free of soy and gluten. Naked Nutrition’s products are certified gluten-free, so those with celiac disease or a gluten intolerance can trust this product.

The company’s customer service was not only easy to access via live chat, but also impressively responsive, quickly addressing our inquiry even outside regular business hours.

What customers are saying

Naked Nutrition Goat Whey Protein Powder has 764 Amazon reviews, with many reviewers noting how easy the product is to digest.

“I like that there are no artificial sweeteners or other additives, just pure goat’s milk. This doesn’t bother my stomach like cow’s milk whey protein powder.”

Jean K., verified Amazon customer

“I like it, it has a very slight goat milk flavor but nothing too bad,” Nermine H. said. “I love the quality and it doesn’t get me bloated and digests well.”

While most reviewers enjoy the goat protein powder overall, the price point was a sore spot for many customers.
“The only reason I gave it a 4 instead of a 5 is that it’s kind of expensive,” Max H. wrote.

Specs

Rating 4/5
Third-party testing Yes
Servings 30
Cost per serving $2.33
Protein type Goat whey protein concentrate
Protein per serving 23 grams
Calories per serving 110
Carbohydrates per serving 2 grams
Fat per serving 0.5 grams

Best clean keto protein powder: Orgain Keto Collagen Protein Powder

a closeup of a container of Orgain's Keto Collagen Protein Powder for hair, skin, nail, and joint support

Best Clean Keto Protein Powder

a closeup of a container of Orgain's Keto Collagen Protein Powder for hair, skin, nail, and joint support
This collagen-based protein powder is as keto-friendly as it is clean, with only a handful of ingredients
Fortune Score:
3.7 / 5

Key product features

Fortune Icons
Flavors 2
FI Third Party Testing
Sugar None added
FI Diet Type
Carbs Low
FI Shipping Mattress
Subscription Available

What you should know

Completely free of additives, Orgain Keto Collagen Protein Powder supplies 10 grams of protein in each 90-calorie scoop.

  • This is an excellent option for people following a keto diet.
  • At $2.10 per serving, this costs slightly above average compared to other protein powders on the market.
  • It’s naturally sweetened with stevia extract.
Pros
Made with easily absorbed collagen peptides
No artificial sweeteners, colors, or flavors
Iron-rich
Less than 100 calories per serving
Cons
Not third-party tested
Only available in two flavors
Only 20 servings per container

Why we like Orgain Keto Collagen Protein Powder as best keto

If you’re a follower of the keto diet—eating low carb and higher fat foods—you might be searching for a clean protein that fits the bill. We like Orgain Keto Collagen Protein Powder, a grass-fed bovine collagen protein powder with just six ingredients that’s completely free of additives.

It’s fairly common for keto fans to keep a close watch on their calorie intake in the name of weight loss. That said, this protein powder only supplies 90 calories per scoop. Its fat comes from medium-chain triglycerides (MCTs), which may lower symptoms of keto-induction according to one study. ( 24 )

“While some symptoms of keto-induction may be lower, those who experience abdominal pain may have greater symptom frequency and severity. But, if that is not a symptom you deal with, this protein is a great option.” ( 24 )

Jen Roper, Ph.D., CSCS, Fortune Recommends Advisor

Orgain Keto Collagen Protein Powder is allergen-friendly and suitable for those who are soy-free, gluten-free, and dairy-free. Plus, it contains 25% of the daily value of iron. But the product isn’t free of drawbacks. Keep in mind, it only provides 10 grams of protein, to satisfy the keto 2:1 ration. It’s common for protein powder users to want at least 20 to 30 grams of protein per serving, but since this is a keto-specific formula, there’s much less.

It’s important to keep in mind that collagen should be considered more as a means of providing functional peptides (short protein fragments) that support body connective tissue health, not necessarily meeting general daily protein requirements.

“Collagen is a poor form of protein itself, with little effect on protein synthesis,” says Mohr. ( 25 ) “While collagen may have other beneficial outcomes, it shouldn’t be used with the intention of providing quality protein to the diet and particularly not in place of other, high quality protein options like a whey protein isolate.”

This protein powder costs right around average, at $2.10 per serving. And with only 20 servings per container, you may run out of it fast. Like many other brands, Orgain does have a subscribe-and-save option that will save you 15%.

What customers are saying

Orgain’s Keto Collagen Protein Powder has over 15,500 reviews on Amazon. While reviews on taste are mixed, most customers agree that the product mixes well, particularly in hot beverages like coffee.

“Orgain’s keto protein powder has become my go-to choice for maintaining a low-carb lifestyle. The taste is fantastic, and it mixes well with both water and almond milk. I appreciate that it’s not overly sweet, and the smooth texture makes it enjoyable to drink.”

Lauren Hudson, verified Amazon customer

“There are many good brands of hydrolyzed collagen powder, this one seems to have the best flavor for the price,” wrote an anonymous verified Amazon customer.

Some reviewers noted how they wished each serving contained more protein, as they felt 10 grams per serving was too little for a protein supplement.

Specs

Rating 3.7/5
Third-party testing No
Servings 20
Cost per serving $2.10
Protein type Bovine collagen
Protein per serving 10 grams
Calories per serving 90
Carbohydrates per serving 3 grams
Fat per serving 5 grams

Best clean plant-based protein powder: Cymbiotika Plant Protein

a close-up of a dark green bag of Cymbiotika's Plant Protein supplement on a white oak surface against a bright green background, with a scoop of the powder sitting in front of it

Best Clean Plant-Based Protein Powder

a close-up of a dark green bag of Cymbiotika's Plant Protein supplement on a white oak surface against a bright green background, with a scoop of the powder sitting in front of it
This protein powder blends organic hemp, spirulina, and pea protein as well as greens, fiber, digestive enzymes, and probiotics.
Fortune Score:
3.2 / 5

Key product features

FI Workout Type
High protein 20 grams per serving
Fortune Icons
Flavor Vanilla
FI Insurance Accepted
Fat Low
FI Shipping Mattress
Subscription Available

What you should know

Cymbiotika’s formula supplies 20 grams of protein from organic hemp, organic spirulina, and organic pea protein.

  • Our testers found the initial flavor to be smooth, but followed by an earthy aftertaste.
  • It’s more expensive than average, at $3.67 per serving.
  • It’s good for those who want more than protein, but plant nutrients and digestive support too.
  • It provides fiber, digestive enzymes, prebiotics, and probiotics to support gut health.
  • The formula is made up of proprietary blends.
Pros
Easy to mix
No artificial dyes or sweeteners
Allergen-friendly
Offers 100% of the daily values of vitamins E and K
GMP-certified
Cons
No third-party testing
Only available in one flavor
Has an earthy aftertaste
Expensive compared to other similar products
Contains proprietary blends

Why we like Cymbiotika Plant Protein as best plant-based

Cymbiotika Plant Protein is our pick for best clean plant-based protein powder thanks to its blend of 20 grams of protein and organic ingredients that include greens, prebiotics and probiotics , and significant amounts of other essential nutrients including fiber, iron, and vitamin E. The formula also includes L-glutamine, which may help with weight loss and performance fatigue, which could help extend your workout. ( 26 , 27 ) Alpha-GPC is also present in small amounts in the supplement, which helps maintain choline levels and may therefore benefit athletic performance and muscle protein synthesis. ( 28 )

Our testers liked the nutrient profile of this blend, with its 130 calories, 10 grams of carbohydrates, and 2.5 grams of fat. Overall, Cymbiotika Plant Protein has more carbohydrates than other protein powders, which are critical for exercise. Additionally, you’ll get 100% of the daily value for vitamin E and vitamin K, and 25% of your daily value for iron. The sodium content, at 17% of the recommended daily intake, is worth paying attention to, since the American Heart Association notes excess sodium may increase your risk for heart condition. ( 29 )

When adding the blend into a shaker cup, our testers found it was easy to mix despite its slightly grainy texture. Our testers also noted an unexpected, earthy aftertaste that followed the product’s original vanilla flavor. This might be because the ingredients list carries a wide range of raw greens, adaptogenic mushrooms, and fiber-rich ingredients.

One thing to consider before purchasing this blend is that it contains multiple proprietary blends, which appear on the supplement facts label as grouped ingredients under one title. The problem with proprietary blends is that it conceals the amount of each ingredient in the formula. Further, there was no sign of third-party testing.

Ease of digestion is another thing to note when discussing this protein powder. One of our testers had symptoms the morning after drinking this blend. “I have been gassy and bloated since drinking this yesterday, woke up this morning extremely bloated and gassy still almost 18 hours later,” they wrote.

What customers are saying

Cymbiotika’s Plant Protein has garnered 47 reviews on Amazon. Reviews of the product’s taste were mixed.

“If you’re looking for something that’s not full of junk that will keep you full and doesn’t taste bad, this is great… Just have reasonable expectations and plan on using it in shakes rather than just with milk unless you’re genuinely into earthy flavors.”

Jen S., verified Amazon customer

“This supplement is not necessarily bad tasting, but it does not taste good,” Joseph S. added.

Specs

Rating 3.2/5
Third-party testing Unknown
Servings 24
Cost per serving $3.67
Protein type Hemp, spirulina, and pea
Protein per serving 20 grams
Calories per serving 130
Carbohydrates per serving 10 grams
Fat per serving 2.5 grams

Best clean protein powder for muscle gain: Vital Proteins Vital Performance Protein Powder

a closeup of Vital Protein's Vital Performance Protein chocolate shake in its container

Best Clean Protein Powder for Muscle Gain

a closeup of Vital Protein's Vital Performance Protein chocolate shake in its container
The bovine-collagen protein powder boasts a minimal ingredient list while delivering a protein count of 25 grams per scoop.
Fortune Score:
4.8 / 5

Key product features

FI Workout Type
High protein 25 grams per serving
Fortune Icons
Flavors 4
FI Diet Type
Fat Low
FI Shipping Mattress
Subscription Available

What you should know

Vital Proteins stands out above the rest thanks to an ingredient list that provides 25 grams of protein without any unnecessary fillers.

  • At about $1.43 per serving, Vital Proteins is a more affordable option than many others on the market.
  • This is best for people looking to build muscle and promote healthy tendons, bones, and joints.
  • For those looking for an energy boost, the cold brew coffee flavor has 100mg of caffeine.
Pros
Third-party tested
May support bones, tendons, and joint health, as well as muscle
Affordable
NSF-Certified for Sport
GMP-certified
Cons
Not suitable for vegan or dairy-free diets
Only available in four flavors
Only 21 servings per container

Why we like Vital Protein Vital Performance Protein Powder as best for muscle gain

We chose Vital Protein Vital Performance Protein Power as the best clean protein powder for muscle gain because it supplies 25 grams protein from bovine collagen and milk protein isolate, and has a minimal ingredient list.

Collagen protein is abundant in muscle tissues. ( 30 ) Since collagen contains unique peptides that can promote the production of collagen in our body, research says it may promote the building of connective tissue proteins, which may support muscles. ( 31 ) While researchers are still studying the connection between collagen and muscle development, we found this protein powder to have a few exemplary qualities that many kinds of athletes can benefit from.

The protein powder contains 130 calories, no fat, and 6 grams of carbohydrates from glucose, an energy source. It also includes MCT oil, which contains medium-chain fatty acids that can be absorbed and readily available as an energy source for muscle. ( 32 )

Vital Proteins gives customers four flavor options to choose from: chocolate, vanilla, strawberry, and cold brew coffee. One downside is that there’s no unflavored option for those who may prefer a flavorless powder to add to coffee or shakes. If you workout into the evening, keep in mind that their coffee flavor has 100mg of caffeine.

“It’s also important to consider other sources of caffeine that you ingest throughout the day, as the maximum recommended intake is 400 mg per day. Additionally, caffeine is known to impact sleep quality, which is vital for exercise recovery.” ( 33 )

Jen Roper, Ph.D., CSCS, Fortune Recommends Advisor

We like that Vital Proteins products are made in an NSF-certified and cGMP-certified facility so we know manufacturing standards are up to par. Their products also undergo third-party testing, however, those reports don’t appear on their website.

“NSF Sport Certification is important to me, as a sports dietitian, since it ensures the product is safe for athletes and that there are no banned substances included in the product itself,” says Mohr.

Additionally, this collagen protein powder is more affordable than many others on this list, costing $1.43 per serving.

If you have any problems with your order, their customer service is fairly quick and painless. The website’s live chat option gets you connected to a real person, quickly, which we greatly appreciate.

What customers are saying

The Vital Performance Protein Powder has nearly 5,000 reviews on Amazon, with many customers singing the praises of the powder’s quality.

“Good alone or mixed with other shakes. Nice combo of whey and collagen,” Joe V. wrote.

“I have tried many expensive powders that are gritty and leave me feeling bloated. This one is the best so far… I am very hopeful that it makes a difference for my training. Mixed the vanilla with water in a smoothie.”

J. Parker, verified Amazon customer

Nutritionally, a few customers aren’t happy that the product contains added sugars, coming from glucose, which seems to be an ingredient mainly used as a carbohydrate or energy source.

Specs

Rating 4.8/5
Third-party testing Yes
Servings 21
Cost per serving $1.43
Protein type Bovine collagen and milk protein isolate
Protein per serving 25 grams
Calories per serving 130
Carbohydrates per serving 6 grams
Fat per serving 0 grams

Best clean protein shake: Slate Milk High Protein Shake

a closeup of a 24-pack of Slate Milk High-Protein Shake cans, french vanilla flavor

Best Clean Protein Shake

a closeup of a 24-pack of Slate Milk High-Protein Shake cans, french vanilla flavor
Slate Milk’s ready-to-drink milk-based shake packs 20 grams of protein per can.
Fortune Score:
4.3 / 5

Key product features

FI Workout Type
High protein 20 grams per serving
Fortune Icons
Flavors 7
FI Diet Type
Fat Low
FI Insurance Accepted
Carbs Low
FI Third Party Testing
Sugar None added
FI Shipping Mattress
Subscription Available

What you should know

At 20 grams of protein per shake, Slate Milk High Protein Shake is a convenient option for consumers looking for a lactose-free protein boost.

  • At about $3.00 per can, these shakes are a more expensive protein option.
  • This is a great choice for people who are lactose-free and looking for something that’s easy to digest.
  • The energy varieties contain caffeine.
Pros
Available in variety packs
Build-your-own box option
Portable
Lactose-free
Cons
Energy varieties are not suitable for those with caffeine sensitivity
More expensive than average

Why we like Slate Milk High Protein Shake as best clean protein shake

We like Slate Milk High Protein Shake as the best clean protein shake because it’s a simple, on-the-go option teeming with 20 grams of protein from ultra-filtered milk and good nutrition. Aside from its richness in protein, the protein shake is low in fat, only has 100 calories per serving, and is free of added sugars. The supplement comes in seven flavors, including classic chocolate, mocha, and french vanilla. The brand also lets you order a combination of flavors in their variety pack, so you can try more than one at a time.

We also like that Slate Milk has an energy variety pack option, with latte shakes that contain caffeine for a morning protein pick-me-up. However, it has almost as much caffeine as two cups of coffee, so if you’re caffeine-sensitive, you may want to consider another flavor or the time of day you’re drinking it.

“As someone who is caffeine sensitive, I tend to avoid all things caffeine. Otherwise, you may experience some unwanted side effects such as jitters, anxiousness, and upset stomach to name a few. So, be mindful of your normal intake to avoid these effects.” ( 34 )

Jen Roper, Ph.D., CSCS, Fortune Recommends Advisor

The brand is mindful of people with lactose intolerance. Their ultra-filtration processing effectively removes lactose from the shakes. The shakes are also low in carbohydrates so they’re suitable for those following a keto diet, too.

Conveniently, Slate Milk is shelf stable so you don’t have to worry about it going bad quickly. That said, you may question how “clean” the product is because of some of its ingredients; but without some of them—like dipotassium phosphate—the product would go bad faster. It’s worth noting that almost all ready-to-go protein shakes on the market include a source of gum, which helps with thickening and stabilizing.

In addition to offering a quality source of protein, the ready-to-drink shake also offers 25% of the daily value of vitamin D, which has numerous benefits and has been defined as a shortfall nutrient in the diets of Americans. ( 35 ) Not to mention, there’s plenty of calcium and vitamin A at 40 % and 25 % of the daily value, respectively.

What customers are saying

Slate Milk High Protein Shake has 1,575 reviews on Amazon, the majority of which are positive. Customers particularly like how the shake keeps them satisfied longer than other products.

“This is my first time trying this brand. I have many protein shakes that have left me more hungry an hour later,” verified Amazon customer J. Flemming wrote. “This shake holds me over for hours!”

“Delicious and filling drink. I’ve really enjoyed how I feel after having this High Protein Shake. I will definitely be ordering more.”

Adam, Amazon

Some reviewers wrote how they noted an aftertaste with some of the flavors, particularly vanilla and chocolate. “Classic chocolate and dark chocolate are pretty good,” Savannah A. wrote. “The classic chocolate has more sweet aftertaste but its not bad. The vanilla was horrible. I wouldn’t drink it.”

Specs

Rating 4.3/5
Third-party testing N/A
Servings 12
Cost per serving $3.00
Protein type Milk
Protein per serving 20 grams
Calories per serving 100
Carbohydrates per serving 2–15 grams
Fat per serving 1 gram

How we test supplements

Our team understands the role supplements play in enhancing your health and wellness. When it comes to choosing the best clean protein powder, it’s important to consider the ingredients and how the product makes you feel, as well as how it impacts your fitness goals.

Our goal is to provide you with easy-to-understand insights that help you make the right choice for your own health and wellbeing.

You read our full supplement testing methodology here.

Testing criteria

Efficacy—40%

Consumers take dietary supplements to achieve specific goals and improve their overall wellbeing. That’s why our main focus when we evaluate protein powders is efficacy. Before recommending anything, we need to make sure a product delivers on its promised benefits.

Here’s what we look for when assessing efficacy:

  • Clinical evidence
  • Calories per serving
  • Dose efficacy
  • Synergistic effects
  • Proprietary blends
Safety and side effects—35%

Our top priority is consumer safety. Before recommending a product, we examine its potential health risks, adverse effects, and safety profiles.

We evaluate:

  • Reported side effects
  • Third-party testing
  • Manufacturer accreditation
  • Artificial sweeteners
Value—20%

Value doesn’t just imply price—we look at a product’s value based on what you receive for the price you pay. Finding a high value protein powder doesn’t mean finding the cheapest option, but identifying a product that provides the health benefits, quality, efficacy, and satisfaction you’re looking for at a price that’s fair.

The main thing we look at in this rating is:

  • Price per serving
Customer experience—5%

Customer experience can make or break how you feel about a product, and how likely you’ll be to buy that product again.

To evaluate customer experience we assess:

  • Ease of purchase
  • Shipping and returns
  • Customer support

About our chemical lab analysis

Our dedicated team of product testers have hands-on experience using the protein powders we evaluate. In this article, we incorporate their insightful feedback, including both the positive and less favorable aspects of each supplement. However, our commitment to transparency doesn’t end there.

To guarantee the products we recommend are from reputable brands adhering to industry best practices for quality and safety, we took the extra step of subjecting them to independent, third-party testing through ISO 17025 accredited lab Ellipse Analytics. Many of the products underwent thorough analysis for safety, purity, and ingredient accuracy. The testing confirms the accuracy of ingredient amounts and ensures the absence of harmful levels of contaminants, pesticides, heavy metals, bisphenols, and phthalates.

The results of these assessments are incorporated into the individual reviews.

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.


What is clean protein powder?

A clean protein powder is a subjective term that doesn’t have a true definition, according to Alyssa Pacheco , RD, from The PCOS Nutritionist Alyssa.

“Typically, it refers to protein powders that have simple, minimally processed ingredients and don’t use “extra” ingredients like fillers and artificial sweeteners,” she said.

Benefits of clean protein powder

Clean protein powders help you build lean muscle during workouts and repair muscle during recovery rest days. These protein powders may also aid in weight loss because they tend to have less extra calories and sugars. Studies show that grass-fed cows, which are generally where clean protein powder comes from, produce milk higher in antioxidants and proteins than cows with other diets. ( 36 )

How we chose the best clean protein powder

Price

High-quality protein powders have a reputation for being high-ticket. Because budget is a concern for many, we’ve outlined the protein powder’s cost per serving for each category. In our list, protein powders range between $1.43 to $3.67 per serving; therefore, many protein powders cost around $2.00 on average. Some companies offer discounts when you subscribe or sign up for the first time. But price is something important to consider, because more often than not, you’re looking for a protein supplement for the long-haul.

Protein per serving

On average, protein powders pack around 20 grams of protein per serving. Some may want more protein while others might look for a different balance of carbohydrates to protein, depending on their overall goal. That’s why protein per serving played into our top choices. While one of our selections contains less than 20 grams of protein, it is specific to those following a keto diet who have to closely monitor protein intake. Also, because it is collagen, which is supplemented to deliver collagen peptides, total protein content is less important than how much peptides are provided.

Ingredients

We prioritized brands making formulas with the fewest ingredients possible, or formulas with natural ingredients such as whole foods. Artificial sweeteners such as sucralose, aspartame, and sugar alcohols are non-nutritive but common in protein powder supplements on the market. Here, we’ve only included those with natural sweeteners such as stevia and monk fruit. We also limited our selection to those without any fillers or thickeners like gums; however ready-to-drink shakes, such as the Slate Milk High Protein Shake, require a gum to stabilize the mixture of ingredients.


What to look for in clean protein powder

The growing number of available protein powders can be overwhelming. But, the truth is, choosing the best clean protein powder comes down to several factors: the protein source, your fitness goals, cost, and taste.

Protein source

Your dietary needs drive what source of protein is best for you. If you’re lactose intolerant, you could choose either a lactose-free whey protein or a plant-based protein. However, if you’re following a dairy-free diet, your options are limited to plant-based proteins only. Moreover, if you’re a person living with digestive issues, you may consider options that include probiotics and/or digestive enzymes to help relieve gas and stomach pain.

Fitness goals

Whether you want to lose weight and preserve muscle mass, or you’re training to bulk up, you’ll be focused on the nutrition a certain protein powder provides. For weight loss and retaining muscle, you may seek a lower calorie, high protein option. However, if you’re wanting to add mass, you might be after a higher calorie formula. A moderate amount of calories and protein in a supplement may be fit for you if you are simply trying to increase your protein intake while exercising.

Cost

Protein powders can get costly, and if you’re supplementing daily, you may be replacing your container every month. That said, you want to make sure your protein choice fits your monthly budget.

Taste

Flavors matter when it comes to protein because if it doesn’t taste good, you’re not going to drink it. Some brands make sample packs so you can try out their products without buying a full tub, while others will let you have a refund solely from being dissatisfied with the taste. If sampling the protein powder beforehand isn’t possible, customer reviews can be helpful in guiding your path to the best tasting protein powders.

Other clean protein powders we reviewed

During our evaluation of clean protein powders, we also assessed the following. While they didn’t make our list, they may be good options for some consumers.

  • Momentous Essential Grass-Fed Whey Protein: At $2.70 per serving, this protein powder is a little pricier than some of the other supplements we tried and the non-flavored one clumped up  a bit in the shaker bottle.
  • Naked Micellar Casein: We like that this clean protein powder only contains one ingredient, but the lactose in casein is high, which, for people with lactose sensitivities may experience G.I. upset.
  • Gainful Vegan: This protein powder isn’t third-party tested, which gives us pause. You’re also likely to find another protein powder for less than $3 per serving.
  • Huel Black Edition: We like being able to try protein powders without having to sign up for a subscription, which is why Huel’s Black Edition didn’t make the cut. Additionally, our tester noted a slight aftertaste from this plant-based protein powder.

FAQs

What is the cleanest form of protein powder?

The “cleanest” form of protein powder is one with minimal ingredients that does not contain artificial colors, flavors, additives, or sugars. The label should say the product has been third-party tested to ensure only the ingredients in the nutrition list are in there.

How do I know if my protein powder is clean?

When looking for a clean protein powder, it all comes down to what’s on the nutrition label. Third-party testing and minimal ingredients are the main things you’ll want to assess. If you’re still not sure, reach out to your doctor or a licensed nutritionist or dietitian.

How do I choose a clean protein powder?

Choosing a clean protein powder depends on your goals. If you want to gain lean muscle, you’ll want to prioritize an option that’s high in protein. If you are looking to lose weight, a fiber-rich protein powder may be more of what you’re looking for.

Choosing a clean protein powder depends on your goals. If you want to gain lean muscle, you’ll want to prioritize an option that’s high in protein. If you are looking to lose weight, a fiber-rich protein powder may be more of what you’re looking for.

After careful consideration of quality, nutritional value, protein content, and available flavor options, our top pick is Transparent Labs Whey Protein Isolate. Perfect for people on the path to building lean muscle and gaining strength, the protein powder is jam-packed with 28 grams of protein per serving. Moreover, it provides low amounts of fats and carbs, and provides just 120 150 calories per scoop. Sourced from grass-fed cows on hormone- and antibiotic-free American farms, its clean blend has no gluten, added sugars, or artificial flavors. Lastly, you’ll have plenty of flavors to entice your taste buds given their selection of 15 appealing flavors.

Is whey or plant protein better?

The right answer depends on your lifestyle and goals. If you can tolerate dairy and are looking to build muscle, then whey protein would benefit you. If you follow a vegan or vegetarian diet, or have a dairy allergy, then your best choice would be plant protein.

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


Our experts

Christopher Mohr, Ph.D., RD

Dr. Christopher Mohr is an internationally recognized subject matter expert and speaker and performance coach. He works closely with some of the largest corporations in the world including Deloitte, Delta Airlines, Johnson & Johnson, and more to help busy executives develop the energy to thrive personally and professionally. Chris was a member of the Men’s Health Magazine advisory board for 10 years, co-authored a NY Times Bestseller with LL Cool J, called LL Cool J’s Platinum Workout, and worked as the sports nutritionist for the Cincinnati Bengals and select WWE wrestlers.

Jennifer Roper, Ph.D., CSCS

Dr. Jen Roper is an associate professor of Health and Human Sciences at Loyola Marymount University. She received her Ph.D. in Physical Education, Sports and Exercise Science in 2015 from the University of New Mexico, with a specialization in Exercise Science and Biomechanics. She has been a Certified Strength and Conditioning Specialist from the National Strength and Conditioning Association since 2014.

Robert Wildman, Ph.D., RD, LD, CISSN, FISSN

Dr Robert Wildman (“Dr Rob”) is a globally renowned exercise, fitness, and nutrition expert who speaks around the world on exercise and sport nutrition, and continues to work with professional and elite athletes to achieve their highest level of performance as well as health and fitness. Rob received his Ph.D. from The Ohio State University, earned his M.S. from Florida State University, and earned his B.S. from the University of Pittsburgh. He is also a registered and licensed dietitian.

Lily Moe

Lily is a Brooklyn-based writer and editor with over seven years of experience in health media. As a former Fitness Coach, Lily’s editorial prowess has largely focused on fitness, nutrition, and weight management. She has also spent a fair share of time in testing labs, analyzing everything from protein powders to yoga mats. Her work has appeared in Verywell Fit, Verywell Mind, Health, and more.

Jessica Coulon

Jessica is an editor and writer who specializes in fitness, health, nutrition, and science content. Previously, she was an editor for Popular Mechanics and Bicycling, where she covered pro cycling news, wrote how-to guides, and tested all the latest and greatest bike gear. She was also a regular shoe tester and contributor for Runner’s World. These days, you can often find her skiing or riding her mountain bike, and racing with the F1RE female enduro team.

Kelly Uhler

Kelly has a multifaceted background in elder care, health care, and copywriting. She has worked for organizations such as A Place For Mom and Homecare.com, which gave her the opportunity to work closely with families, providing reliable information to help them make informed decisions about their loved one’s health, safety, and quality of life.

Gaby McPherson

Gaby McPherson

MS, RDN, LDN

About Author

Gaby McPherson, MS, RDN, LDN, is a freelance health and nutrition writer. She holds a bachelor’s degree in nutrition and dietetics and a master’s degree in medical dietetics with a pediatric nutrition emphasis. She’s spent several years educating and helping families boost their nutrition in practical, simple, and realistic ways.

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