10 Evidence-Based Health Benefits of Whey Protein

Health Line

21-05-2025

Whey protein may help promote muscle growth, support weight loss, and manage conditions like diabetes, high blood pressure, and IBD, among other benefits.
Whey is a liquid that separates from milk during cheese production. The protein part of whey is called whey protein.
It's a complete, high quality protein that contains all of the essential amino acids. In addition, it's very digestible and absorbed from your gut quickly compared with other types of protein.
These qualities make it one of the best dietary sources of protein available.
Keep reading to learn more about 10 possible health benefits of whey protein.
1. Whey is an excellent source of high quality protein
As a dietary supplement, whey protein is widely popular among bodybuilders, athletes, and others who want additional protein in their diet.
There are three main types of whey protein powder, which are classified by their final protein concentration:
Concentrate (WPC): equal to or less than 89%
Isolate (WPI): equal to or greater than 90%
Hydrolysate (WPH): variable
WPC is the most common type and is usually the most affordable. WPI typically has the highest amount of protein and the fewest calories, as it's mostly protein. But it's usually more expensive.
2. May promote muscle growth
Protein is one of the most important nutrients for maintaining or preventing muscle loss, especially as you get older. It can support the growth and recovery of cells necessary for muscle energy, tissue growth, and restoration.
Whey protein, in particular, is known as a complete protein because it contains all nine essential amino acids your body needs, but can only be obtained through diet. It's also rich in a branched-chain amino acid called leucine, which is the most growth-promoting of the amino acids.
Some research suggests that whey protein supplementation may play an important role in preventing and managing age-related muscle loss, known as sarcopenia. It may help build muscle mass and improve strength.
However, it's important to note that resistance training should be a key part of anyone's weekly routine to help build muscle, regardless of age. Protein alone cannot support muscle growth.
As such, the most effective strategy for muscle building is a combination of strength training and consuming a balanced diet of high protein foods, carbohydrates, and some healthy fats.
3. May lower blood pressure
High blood pressure (hypertension) is one of the leading risk factors for heart disease.
A 2023 review of 18 studies found that whey protein supplementation may help reduce systolic blood pressure. This refers to the pressure between the arteries when your heart beats. It's the top number in a blood pressure reading.
The researchers also noted that whey protein may affect diastolic blood pressure when consuming more than 30 grams (g) of WPI per day, for 10 weeks, in people with a body mass index (BMI) of 25 to 30.
This effect may be due to a family of bioactive peptides in dairy called angiotensin-converting enzyme inhibitors (ACE inhibitors). In particular, lactokinins.
However, more research is needed to understand whey protein's possible effects on blood pressure.
A 2019 study in people with overweight and mild to moderate hypertension found that taking 30 g of whey protein daily for 12 weeks helped reduce systolic blood pressure, but not diastolic.
The authors concluded that the effects on blood pressure may have been due to weight loss, among other factors.
4. May help manage type 2 diabetes
Type 2 diabetes is a chronic disease characterized by high blood sugar and impaired insulin function. Insulin is a hormone that stimulates the uptake of blood sugar into cells, keeping it within healthy limits.
Research suggests that whey protein supplementation may help manage diabetes in several ways, including:
lowering blood sugar levels after eating
increasing insulin levels and sensitivity to its effects
managing blood glucose levels
increasing levels of fullness
lowering lipids, such as triglycerides
As a result, whey protein may be effectively used as a supplementary treatment for type 2 diabetes.
However, make sure to choose whey protein products that have minimal amounts of added sugars and carbs, as these can impact your blood glucose levels.
5. May help reduce inflammation
Inflammation is part of the body's response to damage. Short-term inflammation can be beneficial, but under certain circumstances, it may become chronic.
Chronic inflammation is a risk factor for many health conditions, including heart disease, diabetes, and arthritis, and it may reflect underlying health conditions or lifestyle habits that could harm health.
A 2022 review found that whey protein supplementation helped reduce C-reactive protein (CRP) and interleukin-6 (IL-6), two key markers of inflammation in the body.
6. May help manage inflammatory bowel disease
Inflammatory bowel disease (IBD) is a condition characterized by chronic inflammation in the lining of the digestive tract. It's a collective term for Crohn's disease and ulcerative colitis.
A 2024 review of human and animal studies suggests that whey protein supplementation may help promote IBD remission and prevent flare-ups by:
secreting an intestinal protein called mucin
reducing inflammation
improving the function of the intestinal barrier
supporting the gut microbiome and improving overall gut health
7. May enhance the body's antioxidant defenses
Antioxidants are substances that act against oxidation in the body. This means they reduce oxidative stress and lower the risk of various chronic diseases.
According to a 2018 review, some in vitro studies found that whey protein may boost natural antioxidant defenses, especially glutathione, which his produced by your body.
However, limited research has examined the effects of whey protein on antioxidants in humans.
The researchers also noted that for whey protein to have any significant antioxidant effects, it must be processed through the gut and enter the bloodstream.
As such, more research is needed to understand the effects of whey protein on antioxidants.
8. May have beneficial effects on blood fats
High cholesterol, especially LDL (bad) cholesterol, is a risk factor for heart disease.
Some research suggests that a combination of exercise and whey protein supplementation may help reduce LDL cholesterol and total cholesterol, especially in people younger than 50 years old.
In studies that lasted 12 weeks or longer, whey protein supplementation also helped reduce triglyceride levels.
9. May help reduce hunger
Satiety is a term used to describe the feeling of fullness we experience after eating a meal. It's the opposite of appetite and hunger, and it should suppress cravings for food and the desire to eat.
Some foods are more satiating than others, an effect which partly depends on their macronutrient (protein, carb, fat) composition.
Some research suggests that protein is the most filling of the three macronutrients. It can help increase several fullness hormones, including:
glucagon-like peptide-1 (GLP-1)
cholecystokinin (CCK)
peptide tyrosine-tyrosine (PYY)
However, not all proteins have the same effect on satiety. Whey protein appears to be more satiating than other types of protein, such as casein and soy, but more research is needed.
10. May help support weight management
Increased consumption of protein is a well-known weight loss strategy.
Eating more protein may help support fat loss by:
increasing feelings of fullness
reducing hunger and cravings throughout the day
increasing the thermic effect of food
maintaining muscle mass
Whey protein has been shown to be particularly effective, especially when combined with frequent exercise and maintaining a calorie deficit.
What are the possible side effects of whey protein?
In general, whey protein is well tolerated when consumed at the recommended dosage. This is usually 25 to 50 g per day (1 to 2 scoops), but some products will include other recommendations on the packaging.
Some people report that taking too much protein may cause mild gastrointestinal symptoms. These possible symptoms may include:
bloating
cramping
flatulence
diarrhea
abdominal discomfort
If you have lactose intolerance, whey protein hydrolysate or isolate may be more suitable than concentrate. It's also important to speak with a doctor before taking whey protein supplements if you have liver or kidney problems.
»More on this: Side effects of protein supplements
The bottom line
Whey protein powder is one of the most common supplements for athletes, bodybuilders, and people trying to increase their daily protein intake.
It may have several health benefits, such as promoting muscle growth and helping to manage conditions like diabetes, hypertension, and high cholesterol.
If you have a kidney or liver condition, speak with a healthcare professional before taking whey protein supplements. They could recommend a proper dose for you or an alternative way to increase your protein intake.