Whey Protein: Potential Benefits, Known Risks, and More

Is whey protein concentrate the same thing as whey protein isolate?

Yes, with differences in protein and fat makeup. While both types are used in nutritional supplements, whey protein isolate typically has a higher percentage of protein content.

Is whey protein safe to use?

Whey protein is considered safe to consume in moderation for most people — large amounts might provide excess, unwanted calories. Avoid it if you have a milk allergy, or are pregnant or breastfeeding. Also, it may interact with some medications, such as levodopa and certain antibiotics, so speak to your doctor and pick a supplement that’s been third-party tested for quality and safety.

When’s the best time to use whey protein?

Your intake of protein from any source should be spaced throughout the day, as your body can only process about 20 to 40 g of protein at once. That said, it’s beneficial to take part of your daily dose of protein about 30 to 60 minutes after a workout to support muscle growth and recovery. Research also suggests that consuming whey protein before a meal may help regulate high blood sugar levels in people with type 2 diabetes.

Is whey protein used for weight loss?

Whey protein alone won’t make you lose weight. But it may help you reduce body weight and fat mass while maintaining muscle when used as part of a diet and exercise regimen.

Can whey protein make you gain weight?

Yes. If you’re underweight or want to gain muscle mass, whey supplements may help you meet your recommended daily protein intake, especially if you don’t have an appetite. If gaining weight isn’t your goal, though, it’s important to pay attention to the calorie content of whey protein products. Eating more calories than you burn will ultimately contribute to weight gain.

Whey Protein: Potential Benefits, Known Risks, and More

Note: The U.S. Food and Drug Administration (FDA) does not approve supplements for safety or effectiveness. Talk to a healthcare professional about whether a supplement is the right fit for your individual health, and about any potential drug interactions or safety concerns.

Read on to learn more about the possible benefits and risks of whey.

Potential Health Benefits of Whey Protein

Whey protein is best known as a workout supplement. Limited research suggests it may have other health perks.

May Boost Muscle Mass and Health

May Help Body Composition and Nutrition

May Regulate Blood Sugar Levels

Larger studies with diverse groups of participants are needed to corroborate these results.

May Support Healthy Metabolic Function

“This evidence is moderate,” says Walker. “Longer-term studies are still needed to confirm these effects.”

May Support Wound Healing

Weight Loss Effect of Whey Protein

Whey protein’s effect on weight loss depends on context, Walker notes. “When combined with a calorie-restricted diet, whey protein has been shown to promote modest reductions in body weight and fat mass, while helping preserve lean muscle,” she says.

This matters because preserving muscle ensures that weight loss comes primarily from fat, not lean tissue, Walker adds.

Potential Risks and Side Effects of Whey Protein

Whey protein is generally considered safe when consumed in recommended amounts. But it’s not regulated by the U.S. Food and Drug Administration (FDA) and therefore not proven for safety or effectiveness.

Eating too much protein in any form can lead to side effects or interactions.

Risks

Side Effects

Forms of Whey Protein

“Whey protein is commonly available in three forms: concentrate (WPC), isolate (WPI), and hydrolysate (WPH),” says Walker. “Any of the three forms will effectively stimulate muscle protein synthesis, and which is best mostly comes down to factors like cost, lactose content, fat, and how easy it is to digest.”

Food Sources of Whey Protein

• Milk (whole, 1 cup): 14 grams (g) of protein, 20 percent of which is whey
• Yogurt (Greek, plain, whole milk, 100 g): 78 g of protein made up of whey and casein (another milk protein)
• Ricotta cheese (½ cup): 1 g of protein (cheese makers heat whey to make ricotta)

How to Select and Store Whey Protein

If your doctor says you can take whey protein, choose and store it properly to get the most benefit. Keep in mind:

Selection

Whatever type of supplement you choose, it’s important to check the label for approval by USP, NSF, or ConsumerLab.com to make sure it’s third-party tested for quality and purity, says Walker.

Lastly, “review the ingredient list for minimal added sugars, artificial flavors, or fillers, and consider protein content per serving to make sure it aligns with your goals,” says Walker.

Storage

Dosage of Whey Protein

Here’s the breakdown of protein doses for different groups:

FAQ

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Roxana Ehsani, MS, RD, CSSD, LDN

Medical Reviewer

Roxana Ehsani, MS, RD, CSSD, LDN, is a Washington, DC–based registered dietitian-nutritionist, board-certified specialist in sports dietetics, and media spokesperson, consultant, a...