Best whey protein isolate powders

Top 5 Best Whey Protein Isolate Powders 

If you’re “just” working out, you might be missing out on some major benefits. An easy (and tasty) way to rev up your body’s ability to build muscle faster is by taking protein drinks made with 100% whey protein isolate (WPI). 

The best whey protein isolate supplements can help you build lean muscle faster, manage your weight, recover from intense workouts more effectively, and minimize muscle soreness. 

The Whey Protein Isolates We RAVE About

Shifted Whey Protein Isolate
Best Overall
SHIFTED Whey Protein Isolate
transparent labs grass fed whey protein review
Best Grass-Fed WPI
Transparent Labs Grass-Fed Whey Isolate 
Kaged whey protein isolate review
Best Tasting
Kaged Whey Protein Isolate
optimum nutrition wpi review
Best Value
Optimum Nutrition Gold Standard 100% Whey Isolate
Thorne WPI Review
Strongest Formula
Thorne Whey Protein Isolate

Table of Contents

why take protein supplements

Why Protein Matters

Muscles are made of protein.

If you want to get stronger, you need to build lean muscle mass through a combination of exercise and sufficient protein consumption. 

Whey protein isolate is just one type of protein supplement, but the unique properties it possesses as a result of an extensive refinement process make it the highest-quality protein powder widely available on the market. 

What Is Whey Protein Powder?

A whey protein powder supplement is a nutritional supplement that provides nutrients the body needs to build, maintain, and restore muscle mass.

Protein supplements are widely sold in powder formulations. Users mix a scoop of protein powder with water and drink it to increase their protein consumption. 

The Difference between Whey Protein, Whey Protein Isolate, and Other Protein Powders

different protein supplements

A protein supplement can amplify the gains you make through exercise, but not all protein powders are equally beneficial. 

Too many protein powders on the market use a formulation full of cheap, low-quality sources of protein, artificial flavors, and sugar. Some protein powders contain as much as two-thirds to nearly the full maximum recommended amount of sugar in a day. Choosing the right protein powder matters. 

What Is Protein?

Protein is a nutrient the body needs to build and repair muscle. In the body, protein molecules are made up of the amino acids that break foods down into nutrients, grow muscle mass, and rebuild and repair tissues. 

Because proteins are so critical to the functions of the body, the National Library of Medicine’s MedlinePlus reported that they are commonly called “the building blocks of life.” Proteins make up skin, hair, bone, and muscle. 

To grow new muscle (as you accomplish by working out) and sustain and repair damage to existing muscle, you need to consume adequate amounts of the macronutrient protein. Eating protein-rich foods like meat and dairy provides this macronutrient. However, fitness enthusiasts who are exercising intensely and working on building muscle need more protein than a typical diet can provide. 

Protein supplements provide a higher concentration of the macronutrient you need to build muscle than you could consume through food alone. Different protein supplements are derived from different sources. 

Types of Protein Supplements

Most protein supplements are derived from animals in some way. Whey protein is an animal-derived protein supplement, as are casein and egg protein. Some protein supplements on the modern market are plant-based. 

Proteins can also be complete or incomplete, depending on whether they include all nine of the essential amino acids the body needs to consume through dietary ingestion. 

Whey Protein: The Basics

Whey protein, the most popular type of protein supplement, is a complete form of protein derived from dairy. Whey is a by-product of the process of converting cow’s milk into cheese. 

For athletes and gym-goers, there’s a lot to love about whey protein. It’s widely considered the highest-quality and most effective protein supplement source available, thanks to the blend of amino acids it naturally contains—particularly the high content of an essential amino acid called leucine—and its easy absorption by the body. 

What Is Whey Protein Isolate?

Whey protein isolate (WPI) refers to a specific type of refined whey protein. Although whey protein as a whole is generally considered the highest quality of protein, not all forms of whey protein are equally beneficial for exercise enthusiasts. Ultra-refined whey protein isolate is a higher quality supplement than whey protein concentrate. 

Whey Protein Isolate vs. Whey Concentrate

Whey contains a healthy dose of protein, but it can also be full of fats and carbs—exactly what most fitness enthusiasts are looking to reduce when optimizing their diet and increasing their protein intake. 

Whey protein concentrate undergoes a less extensive refinement process than WPI. As such, it contains a lower percentage of protein. At best, whey protein concentrate will be a blend of 80% of actual protein by weight and the remaining 20% consisting of carbohydrates and fats. Certain whey concentrate protein supplements may contain even lower proportions of protein (and higher proportions of carbs and fats). 

That’s why WPI is preferable to whey concentrate. More extensive processing allows whey protein isolate to instead contain at least 90% protein, if not more. The processing steps WPI supplements go through reduce the carbs, fats, and total calories that can upend your otherwise healthy diet. 

4 Key Benefits of Whey Protein Powder

wpi health benefits

Protein powder supplements serve to boost an individual’s consumption of protein to help them gain, maintain, and rebuild muscle. 

The benefits of whey protein powder, in general, include the following: 

  • Its effectiveness in providing a high-quality source of protein 
  • The naturally occurring amino acid content, and particularly an essential amino acid called leucine, that supports the building of lean muscle mass 
  • A high degree of digestibility, so the body can easily absorb the protein source

The benefits of whey protein isolate, in particular, are getting significantly more protein and less of the unwanted components—fats, carbs, and extra calories—in each serving. Protein supplements that provide 100% whey protein isolate cost a bit more than lower-quality whey concentrate supplements or supplements that blend the protein sources, but they offer more bang for your buck in terms of enhanced protein consumption. 

Benefit #1: Whey Protein Supplements Build Muscle Effectively

Whey protein’s efficacy in building muscle mass is well-established. In an article published in the journal Nutrition and Metabolism that dates back to 2010, researchers found that dietary protein, and especially whey protein, “stimulate the greatest rise in [muscle protein synthesis]” and “result in greater muscle cross-sectional area when combined with chronic resistance training.” 

Consumption of whey protein can also improve exercise recovery in healthy adults, especially among younger fitness enthusiasts. The extra protein can help restore and rebuild the damage muscles sustain through intense workouts. This can actually reduce the post-exercise muscle soreness you experience, so you won’t be held back by discomfort. 

Benefit #2: Whey Protein Supplements Start Acting Fast

Whey protein is a fast-acting protein, as established by scientific research. Taking whey protein supplements can help you build muscle faster than you could with only the amount of protein you consume through your regular diet. Further, supplements that consist of whey protein begin acting on the body quickly. 

The body can fully absorb an entire serving of whey powder in a matter of two to three hours, researchers reported in a 2018 article published in the Journal of the International Society of Sports Nutrition. That’s about three times faster than the time it would take for the body to digest dietary protein consumed in the form of a cooked egg, according to researchers. 

Once you begin taking whey protein supplements to help you maximize the gains you make in the gym, you’re likely to start seeing results in a matter of weeks. 

Benefit #3: WPI Supplements Contain Optimal Proportions of Protein, Fat, and Carbs

What makes WPI supplements really special is that these refined sources of whey protein give you more of the nutrients you want—protein, of course—and less of the ones you don’t. 

As part of your healthy lifestyle that prioritizes protein consumption, you’re probably striving to reduce your intake of carbs, fats, and sugars. Choosing whey protein isolate supplements over whey concentrate forms of protein allows you to maximize the actual protein you consume. WPI supplements simultaneously cut down on the carbs, fats, and sugars that can negatively impact your diet. 

Benefit #4: WPI Supplements Offer a Better Value

You’ll pay more for 100% whey protein isolate supplements than for whey concentrate supplements, but you’re getting more protein and less of the nutritionally sub-optimal fillers for your money. 

Protein powder supplements are more than a post-workout snack to curb your hunger. They’re an investment in your body and your health. The best such investment is one in which you’re getting a return of at least 90% high-quality protein, with the fat, carbs, and sugar content minimal. Only 100% whey protein isolate supplements, not whey concentrate supplements or whey supplements that blend cheap, lower-quality sources with a small proportion of higher-quality sources, offer this return on your investment. 

How to Use Whey Protein Powder

how to use wpi powder
Just mix in water and enjoy!

Whey protein isolate supplements usually come in powder form. Most brands recommend mixing a scoop with plain water. Mixing can be accomplished by adding the powder and water to a shaker cup and giving it a good shake or by hand with a spoon. 

Protein powder can also be mixed with milk or added to coffee, smoothies, and other foods and beverages. 

The best whey protein isolate powders tend to mix well with water without having a chalky or gritty consistency. They are available in flavors that make the supplement more palatable, ranging from delicious chocolate and vanilla flavors that taste like milkshakes (but healthy) to more complicated flavors. 

When Is the Best Time to Take Whey Protein Powder?

Consuming protein of some kind with every meal may be beneficial for devoted athletes and gym-goers, but there are ideal and less-than-ideal times to take WPI supplements. 

The body is naturally primed to increase muscle synthesis following a workout. Timing your consumption of fast-acting whey protein isolate supplements to align with this period of improved muscle synthesis rates can help you make the most of your body’s natural muscle-building process. 

Ideally, you should take whey protein powder supplements shortly before, during, or after your workout. If you exercise in the morning, you should take protein powder early in the day. After-work gym-goers will take the supplement later in the day. Fortunately, since whey protein powder supplements don’t typically contain stimulants like caffeine, taking them in the late afternoon or evening shouldn’t keep you up at bedtime. If your workout schedule is variable, adjust when you take your WPI supplement to match. 

Potential Side Effects of Whey Protein Powder

Whey protein powder is a dietary supplement, not a pharmaceutical drug or a food. Like other dietary supplements, whey protein powder has been linked to some side effects. Most healthy adults who use whey protein powder in accordance with serving recommendations (that is, not in excess) report few side effects, which tend to be mild and temporary.

Minor Side Effects of Whey Protein Supplement Consumption

The most common side effects of using whey protein powders include digestive issues such as stomach cramps, gas, bloating, and diarrhea, often arising out of lactose intolerance, Healthline reported. 

Because whey protein isolate contains less lactose than protein supplements made from whey concentrate, WPI supplements may be more suitable for users who find that other protein supplements made with whey upset their stomach.  

Nausea and headaches are among other reported side effects of taking whey protein powder supplements. 

Allergic Reactions to Whey Protein

Allergic reactions may occur in people who have an allergy to either whey in particular or cow’s milk more generally. The symptoms that accompany an allergic reaction can range from rashes and hives to runny nose, swelling of the throat and tongue, and even—in cases of severe allergies—anaphylaxis. People with a known allergy to whey or cow’s milk should avoid protein supplements made with whey or other dairy products. 

Weight Gain and Blood Sugar Spikes From Less-Than-Optimal Protein Supplements

Using protein powder supplements that are packed full of sugars, carbs, and fats may also have an unfavorable impact on your health and fitness efforts. While you’re consuming extra protein to help you build lean muscle mass, the added sugars and carbs could leave you gaining weight in the wrong ways. 

Besides causing you to gain fat as well as (or instead of) the lean muscle you were striving for, protein powders that are chock full of sugar and add up to calorie counts as high as 1,200 can cause unhealthy spikes in blood sugar. Blood sugar spikes can lead to “sugar crashes” and symptoms like fatigue and nausea. Over time, high blood sugar levels may cause you to develop full-blown diabetes, as well as vision problems, heart problems, kidney problems, and nerve problems. 

These potential side effects make choosing the best protein powder even more important. If you’re eager to avoid excess calories, sugars, carbs, and fats in your protein powder, choosing a whey protein isolate supplement, in which fats and carbs are largely filtered out through the extensive refinement process, is ideal. 

Serious Risks of Overconsumption of Protein

Using too much protein powder may pose a risk of more serious adverse events. In a 2021 article published in the Canadian journal Applied Physiology, Nutrition, and Metabolism, researchers listed adverse effects on “kidney and liver function” as potential consequences of “chronic and without professional guidance use of whey protein supplementation,” for example. 

Is Whey Protein Powder Safe?

is protein powder safe

Generally speaking, it’s considered safe for active, healthy adults to consume protein powder in moderation. 

The macronutrient protein is safe to consume. In fact, protein of some kind is necessary for optimal health, even if you’re not a fitness enthusiast. The more active you are, the more need your body has for protein to restore and rebuild your muscles. 

One aspect of the safety of protein powder supplements that is important to consider is toxic contamination. In August 2022, Harvard Health Publishing (by Harvard Medical School) reported that contamination of protein powders is alarmingly common. Researchers have found dangerous levels of heavy metals, pesticides, carcinogens, and other chemicals in protein powders. 

If you’re concerned about contamination, you can feel safer by choosing the best protein supplements on the market. Every protein powder supplement on our list has a reputation for using high-quality ingredients, and some are even third-party tested for quality and contaminants. 

How to Choose a Whey Protein Powder

No one protein supplement is going to be the right fit for every unique body and every set of fitness goals. However, we’re confident that one of the five best whey protein isolate supplements we’ve identified will be likely to help you achieve better results from your workout. 

The first thing to keep in mind when choosing the best whey protein supplement is to look for powders that contain 100% whey protein isolate. These powders will be better quality—containing higher proportions of protein and lower proportions of fats and carbs—than whey concentrate supplements. Some supplements market themselves as whey protein isolate supplements, but if you read the fine print, they actually blend whey protein isolate with lower-quality (and cheaper) whey concentrate. 

Consider, too, the amino acid content of your whey protein powder. Protein is made up of amino acids, but the best products on the market often use transparent labeling practices so consumers can see exactly what amino acids they’re ingesting (and how much of each).  

Look for trusted name brands and for new, cutting-edge brands that get their whey protein isolate from high-quality sources and use formulas backed by science. Although value is important in any supplement you’re going to take regularly, don’t reach for the cheapest option available, which is likely to use lower-quality ingredients. With a little research, you can find premium products at competitive, mid-level price points. 

Finally, consider whether you have any specific goals or needs. Some whey protein powders are specially formulated to reduce muscle soreness or to support recovery for serious athletes and hardcore gym-goers who participate in intense workouts. 

whey protein builds muscle

Ranking Methodology: How We Ranked the Best Whey Protein Isolate Powders

Narrowing down the entire market of whey protein powders to the top five best WPI supplements isn’t easy. To make sure we found the best of the best, we based our rankings on the following criteria. 

  • Quality of ingredients: First, we looked for the WPI supplements with the highest quality ingredients. We only considered products that use 100% whey protein isolate, not whey protein blends that just happen to include some whey protein isolate in combination with cheaper whey concentrate. We gave preference to protein supplements that minimized sugars, fats, and carbs while maximizing protein per serving. 
  • Strength: The more actual protein in your protein supplement, the better. We looked for products that not only include plenty of protein per serving but also boast impressive amino acid profiles. 
  • Value: Protein powder supplements, in general, can cost as little as under $1 per serving, but for good protein powder made from high-quality whey protein isolate, you’re going to have to spend a bit more. Every WPI supplement that earned a spot on our top five list has a price point of around $2 per serving or less. Although each product listed has its own strengths and weaknesses, we’ve found each to offer a great value at a competitive price for the quality of their ingredients and the benefits they provide.  
  • Flavor: A bad-tasting whey protein supplement will be a chore to drink, but a good-tasting one will fit seamlessly into your daily routine. The best whey protein isolate supplements are available in crave-worthy flavors that make increasing your protein consumption easy and enjoyable. 
  • Experience: How well does an individual whey protein isolate supplement work? How does it make users feel? How common are side effects? Although every individual’s experience with any given supplement is unique, we evaluated thousands of different users’ experiences with different whey protein isolate powders. 

Best Whey Protein Isolates


SHIFTED Whey Protein Isolate

Ingredient Quality: 100/100
Taste: 100/100
Value: 95/100
Rave Score: 98.3

SHIFTED is a relative newcomer to the supplement industry, but the brand’s commitment to quality ingredients and cutting-edge, science-backed formulations make it well worth watching. Made with serious athletes and exercise enthusiasts in mind, SHIFTED Whey Protein Isolate is our favorite whey protein isolate product on the market right now. It’s the ideal WPI powder supplement for building muscle mass fast, minimizing post-workout soreness, and enhancing recovery after even the most intense exercise.

With an amino acid profile that includes 12 grams of essential amino acids and 5.5 grams of branched-chain amino acids, the supplement contains optimal dosages of every amino acid you need to maximize your muscle gains. A single serving provides 25 grams of fast-digesting complete protein to help your body start building and restoring muscle right away. If you struggle to eat enough protein to meet your fitness goals, this one’s for you—providing 50% of the percent daily value of protein in a single scoop.

We love that SHIFTED Whey Protein Isolate contains just 0.5 g of sugar and no added sugars. Each scoop includes only 2 g of carbohydrates, 1 g of total fat, and 146 mg of sodium. A single scoop is only 110 calories and provides calcium (120 mg), iron (100 mcg), and potassium (160 mg) to help your body thrive. It also includes 2% of your recommended daily fiber intake. There are no proprietary blends, and the formulation is naturally gluten-free. This 100% whey protein isolate powder has everything you want from a protein supplement and nothing you don’t.

Users love the “delicious” taste of SHIFTED’s two flavors of WPI powder, Chocolate Milk and Cookies and Cream. The company’s goal was to produce “a whey protein that tastes as good as it works,” so it’s no wonder users have called SHIFTED Whey Protein Isolate “the BEST tasting whey protein” they’ve tried. Both flavors are rich, silky, and reminiscent of a milkshake or dessert. While the Chocolate Milk flavor tastes like creamy fudge, the Cookies and Cream flavor is reminiscent of rich vanilla ice cream blended with chocolate chip cookie crumbles.

At its cost per serving of around $2—with a 20-serving container amounting to $39.99—SHIFTED Whey Protein Isolate 100% WPI is a premium product sold at a competitive price point. See the full review here!


  • 25 g of protein per serving
  • A science-backed formulation 
  • An impressive amino acid profile with 12 g of essential amino acids and 5.5 g of branched-chain amino acids
  • Very low levels of fats and carbs
  • Rich, delicious flavors that users have praised as “the best” 
  • A competitive price for a premium WPI product


  • Fewer flavor options compared to brands like Kaged and Transparent Labs 
  • Not third-party laboratory tested, as some competitors are

Transparent Labs Grass-Fed Whey Isolate 

Ingredient Quality: 90/100
Taste: 95/100
Value: 95/100
Rave Score: 93.3

The Grass-Fed Whey Isolate supplement by Transparent Labs is consistently a top performer on the WPI powder supplement market. We especially recommend this one if you’re picky about where your animal products come from because the whey is sourced exclusively from grass-fed, hormone-free cows in the U.S.

This entry in Transparent Labs’ ProteinSeries includes 28 g of protein per scoop. With 0 g of total fat and sugar, less than 1 g of carbohydrates and 160 mg of sodium, you won’t find many products on the market that outperform Transparent Labs Grass-Fed Whey Isolate. The formulation also includes 134 mg of calcium, 0.5 mg of iron, and 130 mg of potassium, per the current nutrition facts label.

The company emphasizes “clean” protein, and its formulation reflects that priority with no artificial sweeteners, dyes, or preservatives. It’s also gluten-free.

We love that the versatile formulation is suitable for bulking up with lean muscle mass or for losing weight by replacing existing fat with muscle, so the supplement appeals to a wide audience.

Transparent Labs offers eight tasty flavors of its WPI supplement:

    • Chocolate Peanut Butter

    • Cinnamon French Toast

    • French Vanilla

    • Milk Chocolate

    • Mocha

    • Oatmeal Chocolate Chip Cookie

    • Strawberry

    • Vanilla Peanut Butter

Users genuinely enjoy the taste of this supplement. Flavors like Mocha, French Vanilla, and Cinnamon French Toast are particularly popular.

At a price point of around $2 per serving—$59.99 for 30 servings—Transparent Labs Grass-Fed Whey Isolate offers a value on par with other top-tier WPI powder supplements. Regular users should consider a subscription that would save them 10%, dropping the price to $53.99 per container or around $1.80 per dose.

The biggest complaint users have about the Grass-Fed Whey Isolate supplement by Transparent Labs seems to be availability. Consumers like the option to shop around for the best deals and the convenience of purchasing supplements through trusted retailers. Unfortunately, you can’t order this supplement online through retail giant Amazon or pick it up at your convenience from your local vitamin store. The supplement is only available on the manufacturer’s website at this time—and, users have complained, it’s out of stock too often. When you consistently depend on a product to be part of your fitness routine, this inconvenience and unreliable availability can be a big issue.


  • The highest dose (28 g) of protein per serving
  • Whey is domestically sourced from grass-fed, hormone-free cows
  • 0 g of sugar
  • 0 g of fat
  • Plenty of flavors to choose from
  • A competitive price for a premium WPI product


  • Limited availability
  • Not third-party laboratory tested, as some competitors are

Kaged Whey Protein Isolate

Ingredient Quality: 90/100
Taste: 93/100
Value: 97/100
Rave Score: 93.3

The most affordable supplement on our list is Kaged Whey Protein Isolate, with a budget-friendly cost per serving of less than $1.50. The per-container cost is high—$59.99—but you get 44 servings in the 3-pound container.

Despite the cost savings, you get a full dose of 25 g of protein in each 31 g scoop. We love that the pure whey protein isolate product includes 12 g of essential amino acids—and 6 g of branched-chain amino acids—per serving in the formulation.

With 0 g of fat, 0 g of sugar, and 0 mg of cholesterol, this supplement delivers on its protein promise without ingredients that can wreck your diet plans. Kaged Whey Protein Isolate contains just 2 g of carbohydrates. You’ll also find 150 mg of sodium in each scoop, along with 124 mg of calcium and 159 mg of potassium. The supplement is gluten-free and devoid of artificial colors and flavors.

In addition to the widely available flavors of Chocolate and Vanilla, Kaged makes its Whey Protein Isolate powder in flavors of S’mores, Chocolate Peanut Butter, and Cinnamon French Toast. The manufacturer describes its flavors as tasting “like your favorite ice cream shake,” and users tend to agree. Vanilla and Chocolate Peanut Butter are among the more popular flavors of the supplement. Some users, however, feel that Kaged Whey Protein Isolate tastes slightly too sweet for their liking.

Two aspects of the formulation really make Kaged Whey Protein Isolate special. For one thing, the formulation includes a patented digestive enzyme blend, ProHydrolase, that helps the body quickly break down protein. We also love that the product is third-party tested and has earned recognition as Banned Substance Free by Informed Sport.


  • 25 g of protein
  • 0 g of sugar, fat, and cholesterol
  • Includes ProHydrolase patented enzyme to improve the digestion of protein
  • Plenty of flavors to choose from
  • Third-party tested and recognized as Banned Substance Free by Informed Sport
  • Budget-friendly


  • More sugar than SHIFTED Whey Protein Isolate and Thorne Whey Protein Isolate
  • Too sweet for some users 
  • Compared to SHIFTED Whey Protein Isolate, Kaged Whey Protein Isolate is missing dietary fiber

Optimum Nutrition Gold Standard 100% Whey Isolate

Ingredient Quality: 89/100
Taste: 90/100
Value: 93/100
Rave Score: 90.6

The Gold Standard 100% Whey Isolate protein supplement by Optimum Nutrition offers several benefits. Each serving contains 25 grams of protein. We like that the formulation boasts both essential amino acids and branched-chain amino acids, even if the strength of these dosages falls slightly below competitors like SHIFTED and Kaged, at 11.4 g of essential amino acids and 5.5 g of branched-chain amino acids.

The formulation of Optimum Nutrition Gold Standard 100% Whey Isolate includes low levels of total fat (0 g for the Rich Vanilla flavor and 0.5 g for the Chocolate Bliss flavor), less than 5 mg of cholesterol, and just 1 g of carbs and sugar.

If you want the highest-quality whey protein supplement, don’t confuse Optimum Nutrition Gold Standard 100% Whey Isolate with the similarly named Optimum Nutrition Gold Standard 100% Whey Protein, a separate product that contains 24 grams of protein that is “primarily” but not completely composed of whey protein isolate. What we love about Optimum Nutrition Gold Standard 100% Whey Isolate is that the product consists entirely of pure, ultra-filtered whey protein isolate rather than a mix of WPI and lower-quality whey protein sources.

The two flavors of Optimum Nutrition Gold Standard 100% Whey Isolate, Rich Vanilla and Chocolate Bliss, are somewhat basic but generally well-liked. Some users complain about a slightly artificial or chemical taste, but most users generally enjoyed the flavor and described the taste as less intense than some other brands—in a good way.

Optimum Nutrition sells this supplement in multiple sizes, but regular users should definitely buy it in bulk. Purchasing the 44-serving container at its list price of $72.99 saves 15% compared to the 24-serving container’s list price of $46.99. The cost per serving works out to around $1.96 when purchasing the small container or $1.66 when purchasing the large container.

We love that Optimum Nutrition’s Gold Standard 100% Whey Isolate protein powder supplement is banned substances tested to give athletes—and any fitness enthusiast who is selective about what they put in their body—peace of mind.


  • 25 g of protein 
  • Low in carbs, fats, and sugars
  • Includes both essential amino acids and branched-chain amino acids 
  • Banned substance tested
  • A competitive price for a premium WPI product


  • Slightly lower dosage strengths of amino acids compared to competitors like SHIFTED and Kaged  
  • Fewer flavor options compared to brands like Kaged and Transparent Labs

Thorne Whey Protein Isolate

Ingredient Quality: 94/100
Taste: 87/100
Value: 90/100
Rave Score: 90.3

Each scoop of the Whey Protein Isolate powder supplement by Thorne contains 25 g of whey protein isolate, but that amounts to only 21 g of bioavailable protein. You’ll find a balanced amino acid profile, including branched-chain amino acids, in this supplement.

At 100 calories, every scoop includes 4 g of carbohydrates, 1 g of dietary fiber, 1 g of total fat (including 0.5 of saturated fat), 105 mg of sodium, and 10 mg of cholesterol. The 2 g of total sugars, including 1 g of added sugars, put the sugar content a bit higher than other brands on our list. Still, the sugar content is well in the reasonable range, so a scoop of the protein powder won’t consume your sugar allotment for the day.

The formulation is gluten-free, soy-free, and derived from natural flavors and colors. Thorne includes in its Whey Protein Isolate powder 30 mg of a proprietary blend of bromelain and papain enzymes derived from pineapples and papayas, respectively, to help the body better digest protein. It also includes 94 mg of calcium, 1 mg of iron, and 200 mg of potassium.

The Thorne Whey Protein Isolate is available in two flavors: Vanilla and Chocolate. These flavors sound a bit basic compared to other brands on the market, but overall, most users find the taste of the supplement a positive rather than a negative. Still, taste-wise, this protein powder is one of the weaker options on our list. Users have complained that the taste is something they “need to get used to,” while other top-performing brands generally had more enthusiastic praise for taste. Some users find the taste a bit too sweet, although generally pleasant.

At a price point of $58 for 30 scoops, users pay around $1.94 per serving. Subscription discounts are available, offering savings of 10% to 20%.

One of the biggest selling points of Thorne Whey Protein Isolate is its third-party laboratory testing. Users can rest assured that they are safe from contamination because the supplement is NSF Certified for Sport. This factor is particularly beneficial for athletes in organized sports leagues, who could face penalties if they unintentionally consume banned performance-enhancing substances.


  • Third-party tested and NSF Certified for Sport
  • A balanced amino acid profile that includes essential amino acids and branched-chain amino acids
  • Inclusion of bromelain and papain enzymes to aid digestion and absorption of protein in the body 
  • A competitive price for a premium WPI product


  • A somewhat lower dose of bioavailable protein (21 g) 
  • Fewer flavor options compared to brands like Kaged and Transparent Labs
  • More sugar than SHIFTED Whey Protein Isolate 
  • Users were more likely to find that they “need to get used to” the taste

FAQ: How to Make the Most of Your Whey Protein Isolate Supplement

Now that we have hilighted the best wpi products on the market, let’s talk about how to squeeze the most value and effectiveness out of them.

Who should use whey protein isolate powders?

Whey protein isolate is a good option for people who want to build muscle fast and support the recovery of their muscles following intense exercise.

Choosing WPI powder supplements is particularly important for fitness enthusiasts who want to watch their intake of carbs, sugars, and fats. 

Who should not use whey protein isolate powders?

Some people should not take whey protein supplements, at least not without first consulting their doctor. 

People who have serious allergies to whey or cow’s milk should choose another protein source. Because much of the lactose is filtered out of whey protein isolate, people who are lactose intolerant may be able to tolerate WPI powder supplements, but they should speak to their doctors about the risks and benefits. 

If you are pregnant or breastfeeding, you should consult your doctor before using. Minors (under age 18) and those who have known health conditions or are taking medications should speak to their physician. 

In general, it’s a good idea to talk to your doctor before starting new supplements. 

Can you take whey protein powders every day safely? 

Using moderate doses of protein powder doesn’t mean you need to restrict the consumption of the supplement. You can take whey protein powder supplements daily, but you shouldn’t exceed recommended dosages. 

Can whey protein powders help you lose weight? 

Although whey protein powder supplements help you build muscle, it’s lean muscle mass that you are (ideally) building through exercise and optimal protein consumption. You can use protein powder, in combination with exercise, to help you lose weight. Because whey protein isolate contains less fat, carbs, and sugars than other forms of whey protein, this type of supplement is a better choice for users who are looking to lose weight.  

Which type of protein powder is best for muscle gain? 

To maximize your muscle gain, you want to consume larger amounts of protein—and smaller amounts of fat, carbs, and sugar—with each scoop of protein powder. 

Whey protein isolate is considered the highest-quality source of protein supplementation. WPI supplements provide the highest concentration of protein per serving, with less of the carbs, fats, and sugar that could make you gain fat instead of muscle. 

Jack Kelle

Jack is an entrepreneur, outdoorist, and animal lover with a background in philosophy, psychology, and business. He enjoys music, friends, and family. At RAVE, Jack works as the manager of marketing and content development.