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Whey protein powders are a simple and convenient way to add more protein to your daily intake. Whether you want to gain muscle mass or reduce body fat, we discuss how this popular nutritional supplement can help you accomplish your health and fitness goals.

So, how do you choose the best protein powder when there are so many options? Whey proteins have similar ingredients, but each brand’s formula is unique in terms of additives and nutritional profile. Some whey blends contain digestive enzymes or whole-food add-ins. And, of course, there are different flavor combinations. To help you decide, here are our picks for the best whey protein, plus a complete guide to understanding whey protein powders.

Transparent Labs 100% Grass-Fed Whey is our pick for the best whey isolate protein powder. Whey isolate has the highest protein concentration of the different types of protein powders. It’s filtered during production to have low carbohydrate and fat content, so it’s a good option if you’re trying to reduce your carb and fat intake.

Transparent Labs’ whey isolate protein powder packs 28 grams of protein into each serving—one of the highest on our list. We also like the flavor variety, including unique flavors like Cinnamon French Toast. Bonus: This protein isn’t too sweet, so you can mix it with fruit juice or add it to a fruit smoothie without feeling like you’re drinking a shake made with Fun Dip.

- 3rd party testing with CoAs

- Certificates of Composition for all products on the website

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For a sugar-free protein powder that still hits your sweet spot, Biosteel 100% Whey is the best choice. This whey protein isolate formula delivers 24 grams of protein in 110 calories per serving. It’s naturally sweetened with Stevia, creamy (not chalky) and has only two grams of carbohydrates per scoop. Plus, it’s free from artificial ingredients, GMOs, soy and gluten.

- Fruity Cereal (a limited edition flavor)

 - 3rd party tested

- NSF International Certified for Sport

Gainful makes personalized, one-of-a-kind nutrition products designed for each customer’s physiology, diet and health goals. Each order comes with free, unlimited access to a Registered Dietitian. That level of support is why we think Gainful has the best protein powder for weight loss. Gainful protein powder comes in a monthly supply of unsweetened, unflavored powder with single-serve flavor boost packets you can choose from daily. Gainful powders contain all nine essential amino acids with anywhere from 19–27 grams of protein per serving, depending on your quiz answers.

Produced in a cGMP Facility

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The best whey protein for muscle gain is Kaged Muscle Whey Protein Isolate. It’s made through a micro-ultrafiltration process that leaves behind high-quality protein with zero grams of sugar, fat or cholesterol. Kaged also offers perks for customers, including free U.S. shipping, a loyalty rewards program, a money-back guarantee and discounts for military and first responders. If you’re watching your amino acids, Kaged Muscle Whey contains 12 grams, including 5.7 grams of branch chain amino acids (BCAAs).

- Produced in a cGMP Facility

- Every batch banned substance tested

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Orgain Grass-Fed Whey Protein is our pick for best-tasting whey protein. We like that it has a near-five star rating from thousands of Amazon reviewers. Some even compare the chocolate taste to creamy chocolate milk. The whey is sourced from grass-fed cows in New Zealand and is free from added hormones or antibiotics. Plus, it’s organic, gluten-free, non-GMO, kosher and soy free. Bonus: You can add extra nutrition to baked goods by mixing Orgain into pancakes, cookies and muffins.

- Certified USDA Organic by QAI (part of the NSF International family of companies

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Naked whey is a no-frills protein powder with one simple ingredient in the unflavored version: whey protein concentrate. The flavored versions add only organic coconut sugar and organic cacao powder (chocolate flavor), natural vanilla flavor (vanilla flavor) or dried strawberries (strawberry flavor). It’s sourced from small California dairy farms where the cows are raised without growth hormones like rBGH or rBST and are grass-fed year-round. Naked whey packs 25 grams of protein in each serving with 5.9 grams of branched-chain amino acids (BCAAs) to help the body regulate protein synthesis, metabolism and aging. Plus, Naked Whey offers a 20% discount with a subscription.

- Produced in a cGMP Facility

- Ingredient processing and packaging facilities are FDA approved

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We chose Dymatize Elite 100% Whey Protein as the best budget whey protein because it’s one of the best protein powders at a competitive price. Not to mention, we found this to be a great-tasting powder. It’s made from the three major types of whey protein (concentrate, isolate and hydrolysate). Studies suggest that protein hydrolysates are better digested and absorbed, so they may enter the bloodstream faster. Since the body breaks down each form of protein at a different rate, the combination gives a more time-released protein boost effect. However, since whey protein concentrate dominates the formula, it contains some lactose which could cause an upset stomach in those with lactose sensitivity. It also has a higher calorie content than others on the list, so it’s better for bulking up than losing weight. Dymatize Elite 100% also contains 2.7 grams of Leucine, which the body needs to build muscle.

- Produced in a cGMP Facility

- Certified by LGC Informed Choice

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If you’re looking for the best organic protein source, Garden of Life Organic Grass-Fed Whey is our recommendation. It comes from free-roaming, pasture-raised New Jersey cows supplemented with certified organic feed. Garden of Life Organic Whey is rich in amino acids and lists the amino acid profile online. It also contains two billion colony forming units (CFUs) of a probiotic strain called bifidobacterium. Bifidobacterium is an important microbe that has been studied for its health effects including colon cancer prevention and improved digestion. It has no added sugars, and its natural vanilla flavor is sweetened with organic Stevia and erythritol.

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Hands down the best whey protein for weight gain is Optimum Nutrition’s Serious Mass. This calorie-dense whey protein is designed to support weight gain and muscle building. One serving boosts your dietary intake by a whopping 1,250 calories and 50 grams of protein so your body can bulk up fast. Serious Mass includes 25 vitamins and minerals, 252 grams of carbohydrates, and three grams of creatine in each two-scoop serving size. Users can start with a half serving daily and work up to a full serving if needed.

Certified by LGC Informed Choice

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For the ladies, our top pick for best whey protein is Protein World’s Slender Blend. The proprietary formula contains whey protein concentrate and skimmed milk powder, with guarana, green tea extract, digestive enzymes and a vitamin and mineral blend. The Slender Blend has 22–24 grams of protein per serving, and it’s recommended as a meal replacement, pre-workout low-calorie snack or post-workout shake. Save 35% by signing up for the subscription; you can cancel anytime.

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Whey protein is a concentrated protein source derived from cow’s milk, which contains two major proteins called casein and whey. Whey accounts for 20% of milk protein and is considered a high-quality protein source. Cow’s milk protein is considered a complete protein because it contains all nine essential amino acids in proportions required by the body.

Beyond basic nutrition, bioactive components in whey may offer specific health benefits such as enhanced immune function and cardiometabolic health. Usually, whey is sold in powder form, which can be blended with water or other liquids or added to soft foods. Also, people use whey protein powder in cooking which adds nutritional value to baked goods. Food manufacturers use whey formulations rather than cream, butter or egg ingredients to make high-protein, low-fat products.

When you browse online or at your local nutrition shop for whey protein products, you’ll probably notice different forms of whey. The main difference in the types of whey protein is how they’re processed. When you understand how they’re made, you can better choose the right type for your health and fitness goals. Here are the three most common forms of whey protein.

Whey protein concentrate (WPC) is the least processed form of whey, so it contains the highest levels of lactose (milk sugar), fat, carbohydrates and nutrients. Food manufacturers use WPC to replace fresh dairy and eggs in products like sauces, soups and baked goods because it adds flavor, color and texture and extends shelf-life. However, it has the lowest protein content out of the three—typically 70-80%.

Whey protein isolate (WPI) is made when whey is filtered and processed. It contains the most protein, 90% or more, and less lactose. For this reason, sports nutrition companies often prefer WPI for use in supplements, bars and other protein products because of the higher protein content. However, it lacks some of the beneficial nutrients found in the concentrated form.

Whey protein hydrolysate (WPH), also known as hydrolyzed whey, is produced by a process called partial hydrolysis, which breaks down whey protein for easier absorption. WPH is digested faster than WPC or WPI, so it causes a 28–43% increase in blood sugar levels. Diabetics don’t have to worry about this, though. Protein digestion is slow. In fact, recent research suggests that whey protein improves glycemic (blood sugar) control.

When picking a whey protein product, there are a few things to look for, including the type of protein, taste, nutrition, additives/allergies and price.

Check the ingredients list to see what type of whey the protein powder contains. Some brands will use a blend of whey forms.

Whey proteins come in a wide variety of flavors. You’ll find options from unflavored to vanilla, chocolate orange and summer berries, to name a few. Taste is important because you want a protein supplement you’ll enjoy. When just starting to supplement your protein intake, try a small container or buy samples of flavors you might enjoy and get creative with your add-ins. You can try fruits, flavored nut milk or juices to create new flavors that fit your taste preference.

Check the whey protein label for the amount of protein per serving and factor it into your daily protein intake. Most protein powders have around 25 grams per serving, and 58 grams is sufficient for the average 160 pound person. Also look for calories, fats, carbs, fiber, vitamins and minerals and even amino acid profiles. Make sure that the supplement you choose gives you the maximum benefit without unnecessary add-ins.

Read the ingredients section, too. Look for additives or allergens that you want or need to avoid. For example, labels warn you if the whey powder contains soy or was processed in a facility with nuts. 

The whey protein powders on our list give you a good idea of the price range for whey supplements. Our top picks vary from $1.16 to $3.41 per serving or $33.99 to $94.99 per container, so there’s an option for most budgets.

It depends on your body’s unique needs and health and fitness goals. You should include protein with meals or snacks every three to five hours, but no one should rely solely on whey protein because that would eliminate other nutritious whole foods from the diet.

One whey protein drink per day is reasonable. Check with your doctor if you want to use whey protein to replace more than one meal. 

The isolate form of whey protein could cause hair thinning. Dr. Larry Shapiro suggests that “WPI contains highly concentrated amounts of amino acids that cause the body to increase testosterone, which breaks down into dehydroxytestosterone (DHT), a hormone proven to cause hair loss.” However, no published medical studies show this to be the case.

Yes. Research has shown that whey protein may reduce abdominal fat when combined with weight training.

If overused, whey protein can cause side effects, including kidney or liver damage, aggression, acne and a disruption in gut bacteria

The best way to know if your whey protein is high quality is to read the labels. Check out the whey source, nutritional profile and ingredient list. Quality wheys use traceable, organic and certified ingredients. Also, high-quality whey products avoid fillers and artificial sweeteners. Another sign that you have a good quality whey is when the labels include certifications and seals from third-party approvals. These show that the manufacturer has proven the quality by established standards.

Prices are accurate and items in stock as of publish time.

Sarah S. Falcone, BSN, RN, is a registered nurse, certified yoga teacher, and health content writer with over 15 years of experience in healthcare.