If you’re serious about your protein intake, whey protein isolate may be your top pick when searching through the best protein powders. These protein-rich formulations often feature a lower count of carbs and fat, making them great for athletes looking to keep their macros in check with a dietary supplement while also trying to reap the benefits of protein powder, including muscle growth, increased satiety, and more. (1)(2)
For those that have strolled through a vitamin store before, though, you understand that there are almost too many whey isolate protein powders on the market to count. In an effort to make the purchasing process go down smoothly, we’ve put more than 100 protein powders to the test to separate the best whey isolates apart from the crowd. With help from our in-house experts, here are our favorite whey isolate protein powders on the market today.
The Best Whey Isolate Protein Powders of 2024
- Best Whey Isolate Protein Powder Overall: Transparent Labs Grass-Fed Whey Isolate
- Best Whey Isolate on Amazon: Sports Research Whey Isolate
- Best-Tasting Whey Isolate: Jacked Factory Authentic Iso
- Best Natural Whey Isolate: Legion Whey+
- Best Grass-Fed Whey Isolate: Onnit Whey Isolate Protein Powder
- Best Whey Isolate for Muscle Gain: Momentous Whey Protein Isolate
- Best Whey Isolate for Digestion: Klean Athlete Klean Isolate
- Best Whey Isolate for Recovery: MyProtein Impact Whey Isolate
- Best Budget Whey Isolate: NOW Sports Whey Protein Isolate
Editor’s note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. It’s always a good idea to talk to your doctor before beginning a new fitness, nutritional, and/or supplement routine.
Best Whey Isolate Protein Powder Overall: Transparent Labs Grass-Fed Whey Isolate
With 8 different flavors and 28 grams of whey protein from hormone-free, grass-fed cows, Transparent Labs Whey Protein Isolate is an excellent way to hit your protein macros. Transparent Labs is also offering 25% off sitewide from November 28 through December 3, and all orders over $150 will receive a free gift bundle including a gym bag, shaker bottle, and free samples of popular products.
Specs
- Price Per Serving: $2
- Protein Source: Grass-fed whey isolate
- Protein Per Serving: 28g
- Carbs Per Serving: Up to 3g
- Fats Per Serving: Up to 2.5g
- Available Flavors: Milk Chocolate, French Vanilla, Chocolate Peanut Butter, Mint Chocolate Chip, Vanilla Peanut Butter, Strawberry Milkshake, Unflavored, Dark Chocolate, Oatmeal Chocolate Chip Cookie, Cinnamon French Toast, Sugar Cookie, Mocha, Peanut Butter, Vanilla Oatmeal Cookie, Blueberry Pancakes
If you’re looking for the highest protein whey isolate, you likely want a product with little to no fat or carbs. This whey protein isolate is not only low in both fat and carbs, but it’s also made with all-natural ingredients and 100 percent grass-fed protein. “I love that Transparent Labs Whey Protein Isolate is free from artificial sweeteners, food dyes, and preservatives. You get 28 grams of high-quality protein without any unnecessary fluff,” adds Chelsea Rae Bourgeois, M.S., RDN, LD.
We’re big fans of this protein from Transparent Labs, giving it a 5 out of 5 for formulation. This one packs one of the largest doses of protein of all the other products in this guide — 28 grams per serving. And, it only has up to 3 grams of carbs and 2.5 grams of fat (depending on flavor), so most of your calories come from protein alone. Sadly, this doesn’t have any digestive enzymes or probiotics, which might have been helpful if you have digestive issues with protein.
[Related: New Study on Protein Timing: Even 100 Grams Per Meal Isn’t Wasted]
It also has added electrolytes like calcium and potassium, which are important for hydration and muscle function. We also gave the flavor an overall 5 out of 5. Granted, our tester did try the seasonal Peppermint Hot Chocolate flavor but, “It tasted exactly like that. All I needed was some whipped cream and a mug.”
Regardless of the flavor you choose, you’ll be pleased with the solubility. Our tester had “no issues” mixing this powder with water in their shaker bottle. There were zero clumps or floaties at all. “It’s super smooth, and even though it tastes like hot chocolate, I didn’t get any bloating or upset stomach that sometimes comes with sweet protein powders.”
This powder is on the more expensive side, earning a 3.5 out of 5 for price per serving. One 30-serving container costs $59.99, putting this product at roughly $2 per serving. There are definitely cheaper options out there, but given this one has zero artificial sugars or colors and contains a high protein content, we think it’s worth the cost if it’s in your budget.
Read our full Transparent Labs Grass-Fed Whey Isolate Review.
Best Whey Isolate on Amazon: Sports Research Whey Protein Isolate
Offering 25 grams pf whey protein isolate alongside nearly 7 grams of BCAAs, Sports Research Whey Protein Isolate is a great option for those looking to supplement their diets, build muscle, and enhance workout recovery.
Shopping on Amazon has its advantages, whether it’s the free shipping you get as a Prime member or the fact that sales pop up frequently. Sports Research Whey Protein Isolate, for example, is often on sale via the online retailer, which is a bonus since it’s already one of the more affordable whey isolates we’ve tested. It’s also a quality supp, with BarBend expert reviewer Chelsea Rae Bourgeois scoring its formulation a 4.5 out of 5.
“This is a pretty impressive whey protein powder — just take a look at its amino acid profile,” she says. “It contains 25 grams of protein per serving, including 6.9 grams of BCAAs, but minimal carbs and fat. If you’re looking to increase your protein intake without skewing your other macros, this could be a great option.”
Our tester, BarBend team member Eric Pisko, agreed after trying out the Creamy Vanilla flavor. “Definitely got the vanilla flavor right with this protein and it does have a creamier aspect to it, whether it was taken in water or milk,” he said. “Would rate this as a very good-tasting protein powder. Mixed great in a shaker cup. Not chunky at all and smooth to drink.” Taste and solubility both scored a 5 out of 5. Another tester agrees with this assessment, saying that “Mixing with water was alright, but adding Creamy Vanilla to milk was, true to form, a super creamy experience. This flavor will work very well in smoothies. It’s definitely one of the best-tasting powders I’ve had.”
As Bourgeois notes, though, Sports Research’s basic Dutch Chocolate, Chocolate, and Creamy Vanilla options may be a deterrent for those who desire variety in the taste department. “If you’re prone to flavor fatigue, you might get bored with Sports Research Whey Protein Isolate,” she says.
The formulation also contains tree nuts, a common allergen, and sucralose, an artificial sweetener, so those with restrictive diets or an aversion to artificial ingredients will want to steer clear.
That said, it is Informed Sport-certified, meaning you can rest assured that it’s free of banned substances and that what you see on the label is what you get in every scoop. Bourgeois concludes, “Sports Research Whey Protein Isolate can be an excellent way to bridge the gaps between protein needs and dietary intake.” (3)
Best-Tasting Whey Isolate: Jacked Factory Authentic Iso
Dig into this easily digesting grass-fed whey isolate that provides 25 grams of protein with each lean 110 calorie scoop. It comes in three tasty flavors at a cost-effective price making it a solid choice for nearly anyone.
Specs
- Price Per Serving: $1.33
- Protein Source: Grass-fed whey protein isolate
- Protein Per Serving: Up to 27g
- Carbs Per Serving: Up to 4g
- Fats Per Serving: Up to 1.5g
- Available Flavors: Chocolate Peanut Butter, Milk Chocolate, Cookies & Cream, Blueberry Muffin, Cinnamon French Toast, Unflavored, Vanilla Oatmeal Cookie, Vanilla, Peanut Butter
A protein powder can be rendered useless if it doesn’t taste good: You won’t drink it! So, the best whey isolate protein powder should blend well and you ideally would look forward to drinking it. Because of its excellent solubility and unique flavors, Jacked Factory Authentic Iso fits that description. We gave this Authentic Iso from Jacked Factory a 4 out of 5 for solubility, finding zero clumps, grittiness, or residue in our shakes post-blending.
As for flavor, the company offers a pretty wide range of flavors, which we liked. Our tester tried the Fruity Cereal Splash flavor and was pleased, giving it a 4 out of 5. “This flavor actually tasted like Froot Loops!” they exclaimed. However, it did have a bit of an odd aftertaste—not enough for our tester to dislike it, but worth knowing. It’s likely due to the use of sucralose, an artificial sweetener.
Jacked Factory Authentic ISO whey isolate also undergoes a filtration process to help cut the amount of lactose and fat in the formula, making it (hopefully) a little easier on your stomach. Overall, we gave the formulation a 5 out of 5, as it’s pretty lean (only 120 calories per serving) and most of the calories come from protein (up to 27 grams of protein per serving). However, we don’t love that Jacked Factory is sweetened with sucralose, because artificial sugars can cause digestive upset for some people.
Still, the extra filtration seemed to help one of our testers, who reports: “I usually hate whey protein (sorry!). So I was really surprised that I liked this so much. Toss it in with milk and some ice, and it was an awesome vanilla milkshake. Not chalky or too sweet at all.”
[Related: Is Too Much Protein Powder Bad for You?]
Additionally, “Some flavors provide up to 300 milligrams of sodium, which is a significant portion of your recommended daily intake. If you’re watching your sodium intake for any reason, you might not be keen on this protein powder,” says Chelsea Rae Bourgeois, M.S., RDN, LD.
The price per serving was relatively good at $1.33 per scoop, earning a 4 out of 5 in this category. One container costs $39.99 for 30 servings, which is cheaper than many other products on the market. Still, you can find whey isolates at an even lower price point if you’re shopping on a budget.
[Related: 18 Ways to Eat More Protein to Pack on Muscle Mass]
Best Natural Whey Isolate: Legion Whey+
An all natural, non-GMO, fat-free whey that's cheaper than many competitors, Legion Whey Isolate Protein Powder is made from 100 percent grass-fed whey protein isolate from sustainable dairy farms in Ireland. It's also higher in calcium compared to other powders on the market.
Specs
- Price Per Serving: Starting at $1.32
- Protein Source: Non-GMO whey protein isolate
- Protein Per Serving: Up to 23g
- Carbs Per Serving: Up to 3g
- Fats Per Serving: Up to 6g
- Available Flavors: Dutch Chocolate, Chocolate Hazelnut, Cinnamon Cereal, Apple Pie, Banana Bread, Birthday Cake, Chocolate Peanut Butter, Cocoa Cereal, Cookies & Cream, French Vanilla, Fruity Cereal, Honey Cereal, Mocha Cappuccino, Salted Caramel, Strawberry Banana, Unflavored
Some supplements can be full of fillers, artificial ingredients, and artificial sugars. But Legion’s Whey+ supplement has none of the above and is a 100 percent all-natural formula made with whey protein that’s derived from grass-fed and pasture-raised cows. Plus, our tester says that the Dutch Chocolate flavor tastes like Ovaltine (what a throwback!). “It’s definitely not too sweet, like more artificial powders tend to be,” they say.
When it comes to transparency, Legion makes a clean protein powder that is hard to beat. This whey protein contains no banned substances and is third-party lab tested by Labdoor. The formula is also quite lean at only 120 calories per serving, including up to 6 grams of fat, up to 3 grams of carbs, and up to 23 grams of protein, depending on the flavor. We gave this high-quality formula a 5 out of 5 rating.
Our product tester also loved the flavor and, considering there are 16 flavors to choose from, settling on one may be difficult. “I tried the Cinnamon Cereal and it tasted just like I was eating the real thing,” they said, giving the flavor a 4.5 out of 5. “I wish it were a little bit richer, but it still tasted so accurate.”
[Related: Best Organic Protein Powders]
Chelsea Rae Bourgeois, M.S., RDN, LD adds, “I like the variety offered, and I love that you get more than 20 grams of protein per scoop without all the artificial junk.”
We also had zero problems with solubility, which we consider a big priority. Our tester gave this formula a 5 out of 5 in this category because they noticed zero clumps on the bottom of their shaker bottle and didn’t have to use an actual blender to get the formula to dissolve properly.
One downside? We don’t love their website design, which, we know, doesn’t actually have to do with the product, but it is part of the customer experience. “They have good customer service and great return policies,” our tester said, giving customer service a 4.5 out of 5. “But their website can get frustrating because I get a ton of pop-ups all the time. Just let me buy my protein!”
As far as price goes, Legion is on the pricey side, so we had to give this category a 3.5 out of 5. Typically, this product costs $59.99 for 30 servings, which is about $1.99 per scoop. However, Legion does run sales pretty often, so keep an eye out for discounted prices.
Read our full Legion Whey+ Protein Review.
Best Grass-Fed Whey Isolate: Onnit Whey Isolate Protein Powder
A grass-fed whey isolate includes added ingredients for digestion like seven digestive enzymes and a probiotic (lactobacillus acidophilus). It's also gluten-free, sugar-free, and soy-free.
Specs
- Price Per Serving: $1.99
- Protein Source: Whey protein isolate
- Protein Per Serving: 20g
- Carbs Per Serving: Up to 4g
- Fats Per Serving: Up to 2.5g
- Available Flavors: Vanilla, Mexican Chocolate
When it comes to whey protein, the milk quality is a huge factor. After all, whey is a milk byproduct. Onnit uses milk from grass-fed and pasture-raised cows, so you’re getting a product that’s free of antibiotics and hormones.
Onnit puts a high priority on quality, which our tester loved. However, we did have to dock them a little bit since the actual protein content is a little lower than other whey isolates. This powder has 20 grams per serving, whereas most others have between 25 grams to 28 grams. However, Chelsea Rae Bourgeois, M.S., RDN, LD, did appreciate the inclusion of an enzyme blend in the ingredients, which can help promote good, fast digestion.
Our tester enjoyed the flavor, too, but wasn’t the biggest fan of the consistency, giving a 3.75 out of 5 for taste. “I tried the Mexican Chocolate, and it was good but I wasn’t as pleased with the texture,” our tester said. “It was very thin when you mix it with water, which is how most people drink their protein. The actual flavor did stand out compared to other chocolate proteins, though.” And if you like your grass-fed protein with vegan milk, rest assured: our tester sings its praises with oat milk, too. “It’s super creamy when you mix it with oat milk, same as whole milk.”
[Related: Best-Tasting Protein Powders]
Despite the thin texture, Onnit’s protein earned a 5 out of 5 for solubility. “This powder dissolved almost too well,” our tester said. “I didn’t have any clumps in my shaker cup but still, it was a little too thin for my liking.” For a bit of added thickness, our tester recommended mixing with your milk of choice.
We gave the price per serving an overall 2.25 out of 5. Onnit’s product is definitely high-quality protein but it’s a little bit pricey at $1.99 per serving ($59.95 for a 30-serving container). If this falls within your budget, you’re definitely getting a high-end product. But we understand that paying about $60 for new protein each month can be a bit much.
Read our full Onnit Grass-Fed Whey Isolate Review.
Best Whey Isolate for Muscle Gain: Momentous Whey Protein Isolate
This whey isolate from Momentous offers 20 grams of protein with only 100 calories per serving. In addition to the protein, there's also 90mg of calcium and 115mg of potassium, as well as an enzyme blend to help aid digestion.
Specs
- Price Per Serving: $2.70
- Protein Source: Grass-fed whey protein isolate
- Protein Per Serving: Up to 23.4
- Carbs Per Serving: Up to 3
- Fats Per Serving: Up to 1.5g
- Available Flavors: Unflavored, Vanilla, Chocolate
Momentous Whey Protein Isolate is a great formula for those who want to build muscle. It packs up to 23.4 grams of protein, with up to 3 grams of carbs, and up to 1.5 grams of fat, making it a lean, protein-focused supplement, ideal for those looking to make gains in the gym and recover quickly. Plus, it’ll make it fun to hit your protein goals: “I’d drink this every day based on taste alone,” one of our testers says. “Just like cocoa, except cold.”
Our testers gave this formula a 5 out of 5. In addition to its lean macro profile, this protein contains ProHydrolase, a digestive enzyme blend that may make it easier to digest and absorb the protein.
“I love love love that they link up-to-date research that backs their product’s ingredients. And the use of Prohydrolase makes this product stand out. The research shows that Prohydrolase can increase amino acid concentrations in the post workout setting. Hello muscle gain,” says Chelsea Rae Bourgeois, M.S., RDN, LD.
We also like that this supplement is made with milk from grass-fed cows that have no hormones or steroids. It’s also third-party tested (Informed Choice- and Informed Sport-Certified), so you’re getting exactly what you read on the label.
After mixing the chocolate flavor with water, our tester thought it tasted quite a bit like hot cocoa. “I liked the taste and I’d drink this one again,” they said, giving a 4 out of 5 for flavor. “I mixed it with ice cold water, and it was really smooth and easy to sip. No grittiness.”
We also gave Momentous whey a 5 out of 5 for solubility. This one mixed well in our tester’s shaker cup without needing to use a full blender. We didn’t notice any clumps in the cup and had no issue with chalkiness in the drink.
While we do enjoy this formula, the price is a tough pill to swallow. At about $2.70 per serving, we had to give Momentous a 1 out of 5 for price per serving, considering it’s among the highest on this list.
One 24-serving container costs $64.95, but you can find plenty of high-quality whey isolates for well under $2 per serving. You can subscribe to a monthly delivery for a discounted $55.21 ($2.39 per serving), but we still think that’s pretty pricey.
[Related: Best Protein Powders for Muscle Gain]
Best Whey Isolate for Digestion: Klean Athlete Klean Isolate
For athletes that need a clean option to supplement their competitive training regimens, this simplified protein powder can be just the ticket. The Unflavored nature of this Klean Athlete powder makes it easy to add to your beverage of choice, and the NSF-Certified stamp helps assure you that the formulation is free of any banned substances, unwanted contaminants, and heavy metals.
Specs
- Price Per Serving: $2.68
- Protein Source: Whey protein isolate
- Protein Per Serving: 20g
- Carbs Per Serving: 1g
- Fats Per Serving: 0g
- Available Flavors: Unflavored
Whey isolate protein powders come with some pretty enticing benefits, but are you willing to go for these perks if it means your stomach will be torn up for hours post-consumption? Klean Isolate from Klean Athlete takes away those fears with a formulation that’s easy to drink and easy to digest. In testing, our product tester experienced no side effects, meaning they could go about their workout and regular activities without any sense of bloating, aches, or GI distress. “It’s perfect for smoothies and shakes,” one of our testers says. “I could definitely have this every day, even though it’s unflavored.”
[Related: How Many Protein Shakes a Day?]
We attributed this stomach-friendly makeup to Klean Isolate’s impressive formulation, which we scored at 4 out of 5. In each serving, you get 20 grams of protein, just 1 gram of carbohydrates, and 0 grams of fat. In addition, there’s a full amino acid profile, which can help ignite protein synthesis for better recovery, digestion, and muscle growth. (4)
Klean Isolate also contains sunflower lecithin to help with mixability, which lent heavily in our 5 out of 5 solubility score. “I really liked that this unflavored powder could be mixed with virtually any beverage of my liking,” said our tester, a former Olympian. “I could easily add this to any concoction for a quick hit of protein throughout the day, giving it plenty of versatility, too, when it came to hitting my daily macros.”
As the name suggests, Klean Athlete Klean Isolate is also a top pick for athletes, thanks to its NSF Certified for Sport regulation. We rated the third-party testing at 5 out of 5, as this means that the formulation is free of banned substances and unwanted ingredients, making it a great pick for those that need to abide by specific governing agencies like the International Weightlifting Federation, NCAA, and others.
While the $2.68 cost per serving may be too high for some budgets — whey isolate protein powders can cost as little as $1 per serving — this can still be a viable option for athletes wanting an easy-to-digest powder that can be added to any beverage throughout their day.
[Related: The Best High-Protein Foods to Help You Pack on Muscle]
Best Whey Isolate for Recovery: MyProtein Impact Whey Isolate
For athletes wanting a complete protein solution for post-workout needs, MyProtein Impact Whey Isolate can be just the ticket. A majority of the calories within this formulation are designed to help promote post-workout recovery, and the ingredients contain no added sugars or fat per dosage.
Specs
- Price Per Serving: Starting at $1.33
- Protein Source: Whey protein isolate
- Protein Per Serving: 22g
- Carbs Per Serving: 1g
- Fats Per Serving: 0g
- Available Flavors: Chocolate Brownie, Chocolate Mint, Chocolate Smooth, Cookies and Cream, Mocha, Pistachio, Salted Caramel, Strawberry Cream, Unflavored, Vanilla
After a tough training session, you want to fuel properly to make sure your muscles can recover as efficiently as possible. Recovery is a huge part of the muscle-gain process and without it, you could slow your progress.. MyProtein’s Whey Isolate formula consists of nearly all protein, so your body can focus on repairing damaged muscle fibers. (5) Our testers gave this formulation a 5 out of 5, as it’s only 90 calories, including 22 grams of protein, 1 gram of carbs, and 0 grams of fat. Plus, you’ll look forward to adding it to your recovery routine, as it tastes “absolutely delightful,” according to our tester. “This is definitely the recovery protein for the cookie fiend in your life (maybe that’s you!) to drink on the daily.”
[Related: MyProtein Impact Whey Review]
This protein comes in 9 unique flavors, like Strawberry Cream and Pistachio. Our tester tried the Cookies and Cream and was pretty satisfied, giving it a 4 out of 5 for flavor. “I have no issues with how it tasted, and I actually really enjoyed the flavor,” they said. “It tasted a little more like cookies than cream — it even had cookie chunks in the powder.”
The company does use sucralose as a sweetener, though, so if you’re sensitive to artificial sugars, you may want to opt for a different product.
We had no issues with solubility of this product, giving it a 5 out of 5. The powder dissolved really smoothly in a shaker cup with no clumps or grittiness. “The protein doesn’t clump at all but the flavor I tried had cookie pieces in the formula,” our tester said. “So, some flavors may have little additions like that, which I didn’t mind.”
MyProtein doesn’t offer any third-party testing information, unfortunately, so we had to give them a 2 out of 5 in that category. However, when it comes to cost, this protein is pretty budget-friendly — $1.33 per serving — earning a 5 out of 5 for value. Plus, they sell in bulk sizes, which can help you save a buck.
[Related: Best Post-Workout Supplements]
Best Budget Whey Isolate: NOW Sports Whey Protein Isolate
NOW Sports Whey Protein Isolate is among the most budget-friendly on the market for under a dollar per serving. This supplement is also third-party tested and comes in bulk buy options bat a discounted price.
Specs
- Price Per Serving: Starting at $0.79
- Protein Source: Whey protein isolate
- Protein Per Serving: 25g
- Carbs Per Serving: Up to 2g
- Fats Per Serving: Up to 0.5g
- Available Flavors: Creamy Chocolate, Unflavored, Vanilla
Not everyone can shell out hundreds of dollars each month on supplements. And you don’t need to spend tons of money to get a high-quality whey isolate to help promote muscle gain and recovery. NOW Sports Nutrition’s Whey Protein Isolate is among the most budget-friendly, earning 5 out of 5 points for price per serving from our team. One 5-pound (81-serving) container costs $58.33, which comes out to only $0.79 per serving. Less than a dollar per day for a 25-gram dose of protein is a steal compared to prices of other brands.
[Related: Add These High-Protein Vegetables to Your Diet for a Muscle-Building Boost]
We’re pretty big fans of the formulation and awarded it a 5-out-of-5 score, too. One serving is only 110 calories with 2 or fewer grams of carbs, up to 0.5 grams of fat, and 25 grams of protein. “It’s low in carbs and fat, so it won’t skew your macro count when you’re just trying to increase your protein intake. Plus, its sodium content is low compared to many other protein powders,” says Chelsea Rae Bourgeois, M.S., RDN, LD.
Unfortunately, NOW Sports doesn’t offer a ton of flavor options. You can choose from Creamy Chocolate, Vanilla, and Unflavored. “I tested the Unflavored version and it was pretty much what I expected. There’s a noticeable whey taste,” one of our tester said, giving it a 4 out of 5. “It wasn’t bad at all, but I’d definitely recommend mixing it in a smoothie.”
You can also use it to make your regular old cold brew a bit more bougie (on a budget!). “I used it with cold brew coffee, and it gave it a great boost. I’ve tried a ton of chocolate protein powders, and I have to say that this one was absolutely delicious. The Creamy Chocolate makes a nice mocha with my cold brew, very complementary.”
We did give this product a 5 out of 5 for solubility, though. “It mixed just like you’d hope,” our tester said. “The drink was smooth, and I didn’t notice any chalky taste or clumping.” So, if you only have a shaker cup and blender ball, you should be able to mix this protein perfectly fine.
Read our full NOW Sports Whey Protein Isolate Review.
How We Tested and Chose the Best Whey Isolate Protein Powders
The BarBend team is made up of competitive athletes, certified personal trainers, and lifelong fitness enthusiasts. To determine the best whey isolate protein powders available today, we’ve tested nearly 100 different profiles from the industry’s best brands, using our supplement testing methodology to rate each profile on a scale of 1 (lowest) to 5 (highest). Below are some of the categories and components that played into our rankings.
- Macro Splits: All the best protein powders heavily favor protein as the primary macronutrient, as opposed to fat or carbs. “When choosing a whey protein, pay close attention to the macro split,” says Dr. Jennie Stanford, MD, FAAFP, DipABOM. “You want a version that is almost all, if not completely all, protein. After all, protein is what you are after, not fat and carbs.”
- Digestibility: Whey isolate is the best animal-based protein powder option for those with lactose sensitivities. These powders are so refined that they’re nearly devoid of lactose, though those who are extremely sensitive may still prefer to avoid them.
- Quality Control: Many of the companies in this list perform ongoing third-party testing to analyze contents for heavy metals, pesticides and herbicides, and other impurities, so you won’t have to worry about quality control when you grab one of these supplements off the shelf.
- Flavors: We like variety, so we tried to include powders that have several flavor options available. Each of the picks on this list has a variety of flavors.
[Related: Best Protein Shakes]
Benefits of Whey Isolate Protein Powder
While there are plenty of potential health benefits of protein powders, whey isolates stand out from the pack. The thorough refining process takes more carbohydrates and fats out of the product, providing a supplement that is more pure protein. Whey isolates are meant as a supplement to help increase protein intake to hit macronutrient goals, aid in recovery and growth, or potentially aid in decreased snacking or fat loss. (6)
If you have any pre-existing conditions or dietary restrictions, it’s best to consult your doctor or a registered dietitian to confirm whey isolate is okay for your body. Below are some other perks associated with whey isolate protein powders.
- Muscle Recovery: Whey protein supplementation has been shown to improve muscle protein synthesis (the repair of muscles after being broken down during exercise). (1) Whey isolate may be better at helping jumpstart muscle recovery after a hard workout than some other protein sources, including whey concentrate and plant-based protein powders. (5)
- Increased Satiety: Studies have consistently shown that high-protein diets can increase satiety and assist with weight loss. (2) (8) A scoop of whey isolate is an easy way to boost your satiety. However, it’s worth noting that whey isolates likely cannot keep you satiated enough to be a full meal replacement.
[Related: The Gymgoers Guide to Whey Protein]
How Much Do Whey Isolate Protein Powders Cost?
Whey protein supplements can range in cost, with whey isolates being generally pricier than their whey concentrate counterparts. That’s likely due to the additional refinement and manufacturing efforts that go into purifying the protein and removing extra carbs and fats. (10) Here’s a price comparison of our favorite products:
| Best Whey Isolate Protein Powder Overall | Transparent Labs Grass-Fed Whey Isolate | $2 per serving |
| Best Whey Isolate on Amazon | Sports Research Whey Protein Isolate | Starting at $1.21 per serving |
| Best Tasting Whey Isolate Protein Powder | Jacked Factory Authentic Iso | $1.33 per serving |
| Best Grass-Fed Whey Isolate Protein Powder | Onnit Whey Isolate Protein Powder | $1.99 per serving |
| Best Natural Whey Isolate Protein Powder | Legion Whey+ | Starting at $1.32 per serving |
| Best Whey Isolate Protein Powder for Muscle Gain | Momentous Whey Protein Isolate | $2.70 per serving |
| Best Whey Isolate Protein Powder for Digestion | Klean Athlete Klean Isolate | $2.68 per serving |
| Best Whey Isolate Protein Powder for Recovery | MyProtein Impact Whey Isolate | Starting at $1.33 per serving |
| Best Budget Whey Isolate Protein Powder | NOW Sports Whey Protein Isolate | Starting at $0.79 per serving |
How to Choose Whey Isolate Protein Powders
Whey protein comes in various forms. The most popular kinds of whey you’ll find on the market are concentrate, isolate, and hydrolysate. There are also plant-based proteins and vegan proteins, but we didn’t consider them for this because the list only consists of milk-derived whey isolates.
While the type is a consideration, you’ll also want to think about price, along with flavor availability. Other things to keep on your radar when considering a whey isolate is the macro split and the digestibility of the protein supplement you’re purchasing.
Protein Type
When it comes to types of whey protein, there are three options: whey concentrate, whey isolate, and whey hydrolysate.
Whey hydrolysate is the most processed — to the point where it may be called “pre-digested” — as the enzymes that break it down have already done part of the digestion for you. Like whey isolate, it contains around 90 percent protein by weight and very few fats or carbs, but since it’s already broken down, it’s absorbed faster than isolate or concentrate. It’s also more expensive than both of those.
Similarly, whey isolate is processed — though a little less so than hydrolysate — and contains the same 90 percent protein by weight and little to no carbs or fat. While it may not be absorbed as fast as hydrolysate, it’s more affordable and considered by many to be the best bang for your buck.
Whey concentrate is the more basic, less concentrated form. It’s only up to 80 percent protein by weight, with the rest of the product being fat and carbs. Since whey concentrate is less concentrated and not filtered, it’s also cheaper than whey isolate and whey hydrolysate (which is the most expensive).
Whey concentrate is typically higher in calories and better for those who want to gain weight, while isolate and hydrolysate are trimmed down in fat and carbs (as well as lactose and sugar) for those who are more conscious of those macros. And if digestion is of particular concern, whey hydrolysate allows for optimal processing and absorption — more so than either concentrate or isolate.
Even though hydrolysate and isolate are leaner versions of whey, that doesn’t mean they aren’t good for muscle building and bulking up. Since whey isolate and hydrolysate both have a higher concentration of protein, they do contain more grams of protein per scoop, and can also be used for building lean muscle mass.
[Related: What’s the Best Whey: Concentrate, Isolate, Hydrolysate?]
Price
Whey isolate is (typically) more expensive than whey concentrate. Isolate is more refined and goes through additional processing to give it a higher percentage of protein per serving with fewer carbs and fats. The higher protein concentration and added manufacturing steps are likely what increases the price.
Generally, whey isolates range from $40 to $80 per tub, depending on other factors such as added digestive enzymes, probiotics, specialty diet formulas, and other variables. If you’re not looking to drop that much on protein powder, you’re better off opting for a less expensive formula, like a whey concentrate.
Flavor Availability
Most protein powders on the market will come in some form of chocolate and vanilla flavors, though some companies may make it sound more exciting with names like “Dutch Chocolate” or “French Vanilla Ice Cream.” Things have come a long way in the past decade with many proteins now available in fruit flavors, rather than just rich flavors. Essentially, if you can dream it, there’s likely a protein flavor of it somewhere out there.
Macro Splits and Digestibility
The macro split of a protein isolate and its digestibility go hand in hand. (11) Thanks to the further refinement and removal of most lactose in whey isolate, it may be more easily digested and ideal for people with lactose intolerance or sensitivity. Whey isolates typically have fewer carbs and fats in the way to slow down the digestive process, which may contribute to the quicker absorption and digestion that whey isolates are known for. (9)
Macro splits on whey isolates are usually very lean and (sometimes) even keto diet-friendly with low fat and low carbs (generally less than 2 grams of fat and less than 5 grams of carbs in whey protein isolates).
Some whey isolate formulas even come with digestive enzymes to help digestibility even more. If macros and better digestion are two factors you’re concerned with, a whey isolate is likely for you. But for optimal digestion, be sure you’re leaning toward those formulas with digestive enzymes, even though the isolate should be fairly easy for the body to digest on its own.
[Related: Fat Loss and Muscle Gain: The Right Macros for Your Goals]
Best Whey Isolates FAQs
What is the best whey isolate?
The best whey isolate will depend on a few factors, including goals, your needs, your flavor preferences, or your budget. With that being said, we think Transparent Labs Whey Protein Isolate is a top-tier choice, as it has a high calorie-to-protein ratio, comes in a variety of unique flavor options, and is made from a high-quality protein source.
How much do whey isolates cost?
They’re generally more expensive than whey concentrates at around $1.76 per serving. If you’re looking to cut back on fat and carbs, we think the added cost is worth it. You’re not going to find a whey concentrate option with as little fat and carbs as whey isolates have. However, if that isn’t a priority to you, spending more money on whey isolate will not be worth your while.
Does whey isolate contain lactose?
Yes, it does, but only about 1 gram. Whey concentrate contains around 3 grams, but neither of these numbers are typically enough to affect someone with lactose intolerance.
References
- Hulmi, J.J., Lockwood, C.M. & Stout, J.R. Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutr Metab (Lond) 7, 51 (2010). https://doi.org/10.1186/1743-7075-7-51
- Veldhorst, M. A., Nieuwenhuizen, A. G., Hochstenbach-Waelen, A., van Vught, A. J., Westerterp, K. R., Engelen, M. P., Brummer, R. J., Deutz, N. E., & Westerterp-Plantenga, M. S. (2009). Dose-dependent satiating effect of whey relative to casein or soy. Physiology & behavior, 96(4-5), 675–682. https://doi.org/10.1016/j.physbeh.2009.01.004
- Church, D. D., Hirsch, K. R., Park, S., Kim, I. Y., Gwin, J. A., Pasiakos, S. M., Wolfe, R. R., & Ferrando, A. A. (2020). Essential Amino Acids and Protein Synthesis: Insights into Maximizing the Muscle and Whole-Body Response to Feeding. Nutrients, 12(12), 3717. https://doi.org/10.3390/nu12123717
- Blomstrand E, Eliasson J, Karlsson HK, Köhnke R. Branched-chain amino acids activate key enzymes in protein synthesis after physical exercise. J Nutr. 2006;136(1 Suppl):269S-73S. https://doi:10.1093/jn/136.1.269S
- Vliet, S. V., Beals, J. W., Martinez, I. G., Skinner, S. K., & Burd, N. A. (2018). Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption. Nutrients, 10(2), 224. https://doi.org/10.3390/nu10020224
- West, D. W. D., Abou Sawan, S., Mazzulla, M., Williamson, E., & Moore, D. R. (2017). Whey Protein Supplementation Enhances Whole Body Protein Metabolism and Performance Recovery after Resistance Exercise: A Double-Blind Crossover Study. Nutrients, 9(7), 735. https://doi.org/10.3390/nu9070735
- A Castro LH, S de Araújo FH, M Olimpio MY, et al. Comparative Meta-Analysis of the Effect of Concentrated, Hydrolyzed, and Isolated Whey Protein Supplementation on Body Composition of Physical Activity Practitioners. Nutrients. 2019;11(9):2047. https://doi:10.3390/nu11092047
- Moon J, Koh G. Clinical Evidence and Mechanisms of High-Protein Diet-Induced Weight Loss. J Obes Metab Syndr. 2020;29(3):166-173. https://doi:10.7570/jomes20028
- Bendtsen, L. Q., Lorenzen, J. K., Bendsen, N. T., Rasmussen, C., & Astrup, A. (2013). Effect of dairy proteins on appetite, energy expenditure, body weight, and composition: a review of the evidence from controlled clinical trials. Advances in nutrition (Bethesda, Md.), 4(4), 418–438. https://doi.org/10.3945/an.113.003723
- Morr CV, Ha EY. Whey protein concentrates and isolates: processing and functional properties. Crit Rev Food Sci Nutr. 1993;33(6):431-476. https://doi.org/10.1080/10408399309527643
- Capuano E, Janssen AEM. Food Matrix and Macronutrient Digestion. Annu Rev Food Sci Technol. 2021;12:193-212. https://doi:10.1146/annurev-food-032519-051646
