There are lots of different protein powders out there, whey protein being one of them. But what exactly is whey protein? Is it good for you? Here a registered dietitian answers all of those questions and more.
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Looking to jazz up your breakfast smoothie or post-workout shake with protein powder but feeling overwhelmed with the types of protein powders in the store? With all the different varieties available, it's not surprising that you're unsure what to look for. If you haven't noticed, whey protein is one of the most common protein powders on the market. Read on to find out what it is, its benefits and downsides, the different types of whey protein available and how to choose a whey protein powder that best suits your needs.

What Is Whey Protein?

Whey protein is one of the two proteins found in cow's milk. When milk is used to produce cheese, the curding process separates the curds from the liquid, also known as whey. Whey is a nutrient-dense, nearly translucent liquid consisting of all nine essential amino acids (the building blocks of protein) and vitamins and minerals. The liquid whey is filtered and dried to make whey protein powder.

Whey protein powder is often used as a nutritional supplement, and it can be added to smoothies, shakes, protein bars, meal replacements and more. Because whey is dairy-based, it is not a vegan product. You'll want to look for a plant-based protein powder instead, such as soy, hemp, pea or rice, if you are a vegan.

heap of protein powder on a designed background
Credit: Adobe Stock / Volodymyr Shevchuk

Is Whey Protein Good for You?

Whey protein has some potential health benefits, plus a few drawbacks if you use too much. Here are some of the health benefits of whey protein, plus a few potential side effects to watch out for.

Whey Protein Benefits

1. It can help boost muscle mass

Protein is vital for gaining muscle mass. Eating enough protein may also help prevent muscle loss due to aging. From a medical standpoint, whey protein may be used as a protein source for providing extra nutrition to people who have illnesses and need to gain body weight. Whey can also be the additional protein source for healing wounds after an injury or surgery.

Generally speaking, you should get enough protein from the foods you eat in meals and snacks, including both animal and plant-based proteins, such as meat, poultry, fish, eggs, tofu and legumes. However, from amateurs to professional elites, physically active people may try whey protein to improve their athletic performance and gain muscle strength and mass. In this situation, whey protein is extra protein added to their existing diet.

Whey protein may also be preferred over other types of protein powder, such as casein protein, because the former is more easily digested and absorbed faster than the latter.

2. It may help balance blood sugars

Studies have noted that whey protein might be helpful in regulating blood sugar levels, particularly when it's consumed before or with a high-carbohydrate meal.

3. It may help you lose weight

Another potential benefit is promoting weight loss. We know the beneficial effects protein can have on increasing satiety and making weight loss easier. And studies show that whey protein, in particular, can be effective. One research review in the Journal of the American College of Nutrition found that participants who substituted some foods with whey protein, combined with strength training exercises such as weight lifting, gained muscle mass and lost an average of 4.2 pounds of body weight and 3.74 pounds of body fat.

While whey protein may provide some health benefits, more research is needed to confirm its effectiveness.

Whey Protein Side Effects

Some people may have unpleasant symptoms, such as headache, nausea and cramps, when consuming whey protein in large doses. Individuals who are allergic to or intolerant of the milk protein may also experience adverse reactions if they consume whey protein, a milk-derived ingredient.

Types of Whey Protein: What's the Difference?

You may have come across different types of whey protein, but how do you differentiate one from the other? For instance, what is whey protein isolate versus whey protein? Here we'll break it down.

Simply put, whey protein concentrate (WPC) has a higher concentration of fat and carbohydrate than its counterpart, whey protein isolate. The amount of protein present in WPC can vary between 30 and 80%.

Whey protein isolate (WPI), on the other hand, has more fat and carbohydrate filtered out, leaving a protein concentration of at least 90%. It is also pricier than WPC because further processing is needed.

Whey protein hydrolysate (WPH) is another term for hydrolyzed whey. WPH is the pre-digested or broken-down form of whey protein, allowing for easier absorption. Among the three types of whey protein, this form of whey protein is the easiest to digest. It is also commonly used in specialized infant formulas and medicinal protein supplements.

Whey protein concentrate and whey protein isolate are the most common forms of whey protein available for sale. However, which one you would pick will depend on your budget, needs and goals. For example, suppose you are lactose-intolerant. In that case, you might want to choose the whey protein isolate because more lactose, a type of sugar (also a carbohydrate) found in milk and dairy products, is removed during the filtration process.

How to Choose a Whey Protein Powder

In addition to choosing the type of whey protein that fits your needs, what's in the product is also a key factor to consider.

1. Read the ingredients list

Whey protein powder in its natural form may not be appealing to everyone's palate. Manufacturers may add sugar and flavorings to enhance its taste. Hence, look for a protein powder that lists whey protein as the only ingredient (this way you can add just the right amount of sweetness, if needed) or choose one that is low in added sugars, sweeteners, additives and fillers.

2. Choose a product tested by a third party

Dietary supplements like whey protein are currently not regulated by the FDA to the extent that food products are. Under federal law, the manufacturer can make claims about a product without requiring FDA approval before selling it to the public.

To ensure what you buy is what you get, look for a protein powder that has been approved and certified by a third-party organization, such as the NSF or Informed Choice. By looking for the seal of approval, you can rest assured that the product has been tested, analyzed and verified by an organization independent from the manufacturer. Specifically, the verification looks at the product's ingredients, such as the quantity of protein included, and whether any heavy metals such as lead and arsenic are present.

What Is the Best Whey Protein Powder?

The best type of protein powder for you depends on your needs. But, looking at the ingredient lists and verification from third-party organizations, these two brands are good options.

Naked Grass Fed Unflavored Whey Protein Powder (5 lbs.)
($109.99 save 14%)
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Pure Whey Protein Powder Vanilla (2 lb. bag)
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Bottom Line: Do you need to take whey protein?

Ultimately, your question is: do you need whey protein? As mentioned earlier, you should meet your protein needs—when you eat a nutritious diet—without needing protein supplements. However, you may include protein powders as part of your lifestyle for different reasons.

Some people may take protein powders to improve their endurance and strength as they build and maintain their muscles. Others may add protein powder to their diet for top-up purposes if they are having trouble eating enough protein foods. And, some individuals may use it due to swallowing and chewing problems, as it's easier to ingest protein powder mixed with food and beverages to meet their nutritional requirements.

Whether or not you need that extra protein will depend on your nutritional needs and goals. That said, it's best to speak with a registered dietitian to determine your protein needs before purchasing. And if you do decide to invest a protein powder, look for products from reputable brands with third-party approvals, read the ingredients lists and follow the instructions provided.