Whey Protein: Nutrition Facts, Health Benefits, Side Effects, and More

Whey protein has a reputation for helping bodybuilders bulk up, but this popular supplement can do more than add to your muscle mass. In fact, whey protein may help with weight loss and optimize your overall health, such as by lowering high cholesterol.

Read on to learn more about where whey protein comes from, as well as the possible benefits and risks of incorporating this milk-based ingredient into your own diet.

What Whey Protein Is and Why People Use It

Whey protein is derived from whey, which is more than just a line in a nursery rhyme. Whey is the watery milk substance that separates from curds in the production of cheese, and whey protein is the protein this liquid contains. (1) Dried whey protein is also sometimes used as a binding ingredient in processed meats and other food products. (2)

Most whey protein comes in powdered form. It’s often sold in tubs with scoops you can use to measure out portions for individual shakes and smoothies, giving you an extra boost of drinkable protein. (3) Some formulas are even flavored, so you can simply add water and drink it.

The most common reason people take whey protein is to help boost their athletic performance. In such cases, the protein is taken after a workout, so the amino acids can help the body increase muscle mass and strength and potentially improve muscle recovery. Whey protein may also be recommended for people with nutritional deficiencies. (3)

But before whey protein transforms into the powder supplements that many athletes depend on, it goes through a multistep process. Cow’s milk is transported to a facility for separation. During separation, enzymes help start the cheese-making process, in which the curds and liquid whey separate. The liquid whey is then extracted and processed. (4)

Whey protein typically comes in three forms: whey protein concentrate, whey protein hydrolysate, and whey protein isolate. Whey protein concentrate is commonly used in protein drinks and infant formulas, and it has between 29 and 89 percent protein. (5) It’s also sometimes added to protein bars and baked goods.

Hydrolyzed whey protein is often the version used in sports drinks, medical protein supplements, and infant formula. (5) It contains between 80 and 90 percent protein.

Whey protein isolate has the highest percentage of protein, at 90 percent or more. (5) It’s mostly used in nutritional products, such as drinks, bars, and other supplements.

Whey protein is just one of the many options available for getting enough protein in your diet. As one of the three necessary macronutrients, protein plays an important role in muscle creation, as well as blood, enzyme, and antibody health. (6)

The recommended daily allowance (RDA) for protein is 0.8 grams (g) for every kilogram (kg) of body weight. To figure out how much protein you should be getting daily, multiply your weight in pounds by 0.36. This will be the number of protein grams you need according to your body mass. For example, if you weigh 150 pounds, you need around 54 g of protein per day. Your doctor can help you figure out your ideal intake based on your age, health status, and activity level. (6)

Most people in the United States get enough protein in their diet, but if you have an underlying condition that makes hitting that target difficult, consult your doctor to see if you might benefit from supplementing your diet with whey protein. (1)

The exact nutritional facts differ depending on which whey protein product you choose, such as a powder or bar. Still, the powdered form is what many people think of when they think of whey protein, as this is the type used in workout shakes. The following nutrients are contained in a three-scoop serving of whey protein isolate powder: (7)

• Calories: 309
• Protein: 50 g (100 percent daily value)
• Fat: 1 g
• Carbohydrates: 25 g
• Fiber: 0 g (0 percent DV)
• Sugar: 1 g
• Calcium: 600 milligrams (mg)
• Iron: 1 mg (6 percent DV)
• Magnesium: 200 mg (48 percent DV)
• Phosphorus: 500 mg
• Potassium: 750 mg (16 percent DV)
• Sodium: 320 mg
• Zinc: 7.5 mg
• Vitamin C: 30 mg (33 percent DV)
• Cholesterol: 10 mg

While touted as a way to increase athletic performance, whey protein also may offer a number of potential health benefits. If you don’t get enough protein in your diet, whey protein may be an easy way you can increase your overall intake.

For some people, whey protein may help with weight maintenance. There’s also some evidence that the protein may help deter unintentional weight loss seen in HIV. (3) Some studies have even indicated that whey protein can reduce overall cholesterol levels in adults. (8) Some research suggests whey protein may also benefit infants. If given infant formula containing whey protein in the first 3 to 12 months of life, their risk of developing itchy and red skin by age 3 lessens. (1) Never give your infant whey protein in the form of a dietary supplement, only as an ingredient in infant formula, and check with your child’s doctor before doing that.

Whey protein is also being studied for its possible benefits in: (1,3)

• Chronic wound and burn healing
• Allergies
• Weight gain and maintenance in older adults and for people managing conditions like HIV

For workouts, whey protein is most helpful when eaten after exercise as an aid to muscle recovery. (9)

Can Adding Whey Protein to Your Drinks and Shakes Help You Lose Weight?

Getting adequate protein is essential when you’re losing weight. It helps keep you full while also fueling muscle mass instead of fat (along with exercise). (10) In one study, a group of older adults with obesity who were intentionally losing weight took whey protein, vitamin D, and leucine. Researchers found that this combination helped participants preserve muscle mass — a key benefit, as many people unintentionally lose muscle while also trying to lose body fat. (11)

The caveat is that whey protein isn’t any more effective than other forms of the macronutrient when you’re trying to lose weight. It’s successful when used in combination with a low-calorie diet and exercise plan. In fact, supplementing with whey may contribute to weight gain for people who are trying to drop pounds, notes the Cleveland Clinic.

How Whey Protein Works to Help You Build Muscle

While protein is essential for your overall health, it also helps you build a healthy muscle mass. Your body processes proteins as amino acids, which are the foundation for muscles. Without these amino acids, your muscles won't recover, get bigger, or become more refined — no matter how much you exercise. If you don’t have time to eat a protein-rich meal, a whey protein shake can do the trick.

Selecting the right whey protein can be somewhat of a challenge because the market is saturated with different powders, premade shakes, and bars. Also, while the U.S. Food and Drug Administration (FDA) has deemed whey protein concentrate as “generally recognized as safe,” a weight loss supplement containing whey protein may not necessarily be FDA-approved. (14) You can ask your doctor for specific product recommendations based on why you want to use the whey protein (athletic performance, weight loss, etc.).

Traditional whey protein powder is made flavorless. These can be added to your everyday drinks. Other types have flavors like vanilla and chocolate, which may be added to water or smoothies for a treat.

Powdered whey protein should be kept in a cool, dry place. While whey protein can withstand temperatures of up to 115 degrees Fahrenheit, humidity can destroy the product. Therefore, a kitchen cupboard or pantry is ideal for keeping the product fresh. Liquid whey protein, on the other hand, may be refrigerated. (15)

Unless you have a milk allergy, whey protein is usually safe to use in recommended amounts. (3,16) Eating too much protein in any form can lead to too many calories. You’ll want to discuss your individual protein needs with your doctor before adding whey protein to your diet.

Other possible side effects of whey protein include gastrointestinal discomfort, such as bloating and diarrhea. These are more likely to occur if you have an intolerance to milk, or if you drink too many nutritional supplements. (3)

Women who are pregnant or nursing should avoid whey protein to be safe — there’s not enough research yet on its safety for these conditions.

If you take any prescription medications, you may want to ask your doctor before taking whey protein. It may interact with some medicines, including:

• alendronate (Fosamax)
• albendazole (Albenza)
• levodopa
• certain antibiotics, such as tetracycline (Sumycin) and quinolones (1,3)

If you’re using a powdered form of whey protein for a quick shake, simply follow the product instructions. You can also try one of the following whey protein recipes to mix things up:

• Oatmeal Shake
• Peanut Butter and Jelly Protein Smoothie
• Vanilla Berry Protein Smoothie
• Healthy Strawberry Protein Shake
• Strawberry Banana Protein Smoothie

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

A: The short answer is yes, with slight differences in protein and fat makeup. While both types are used in nutritional supplements, whey protein isolate has the most protein content. (5)

Q: Is whey protein safe to use?

A: Whey protein is considered safe to consume for most people. It’s not safe for people with milk allergies, and it’s not recommended for pregnant or nursing women. Also, it may interact with some medications. Be wary of consuming large amounts of whey protein drinks and other supplements though, as this can make your protein and calorie levels too high. Most whey protein foods are used as meal replacements or post-workout recovery fuel. (3,5,6,16)

Q: When’s the best time to use whey protein?

A: Your intake of protein from any source should be spaced throughout the day and after workouts. (12) If you’re using a meal replacement containing whey protein, drink the shake or smoothie in place of one of your regular meals.

Q: Is whey protein used for weight loss?

A: Eating whey protein alone won’t make you lose weight. But it can help maintain muscle mass when used as part of an exercise regimen — these newfound muscles may help you burn more fat over time. (10,11,12,13)

Q: Can whey protein make you gain weight?

A: While some people use whey protein supplements as a way to lose weight, it’s also possible to gain weight with whey protein. Much of this depends on the amount of whey protein used and what other ingredients are added to a whey protein supplement. If you’re underweight and are looking to gain muscle mass, you can find supplements designed specifically for gaining weight. (3) It’s important to pay attention to the calorie content of various whey protein products. If you’re looking to lose weight with whey protein, you’ll want lower-calorie shakes, and vice versa for weight gain.

Q: Is it safe to have whey protein with a milk allergy or intolerance?

A: No. Whey protein is derived directly from milk. If you have an allergy or intolerance to milk, then taking whey protein can cause symptoms of an allergic reaction, such as hives, swelling, and gastrointestinal upset. (16)

Q: Do I need any special equipment for whey protein drinks?

A: This all depends on the brand you buy. The good thing about most whey protein supplements is that they come in powder form, so you can add them to your drinks at home. But you may need a blender at the very least to prevent any chalky textures. Some companies also sell specialty shakers that combine the powder and beverage together. This approach also saves on the cleanup, as you can drink it right out of the shaker.

• TGS All Natural 100% Whey Protein Powder
• PURE Whey Protein Powder by SFH
• Optimum Nutrition Gold Standard 100% Whey Protein Powder
• Nutricost Whey Protein Isolate
• NOW Sports Whey Protein Isolate