Here are 10 health benefits of whey protein that are supported by human studies.
1. Whey is an Excellent Source of High-Quality Protein
Whey protein is the protein fraction of whey, which is a liquid that separates from milk during cheese production.
It is a complete, high-quality protein, containing all of the essential amino acids.
In addition, it is very digestible, absorbed from the gut quickly compared to other types of protein (1Trusted Source).
These qualities make it one of the best dietary sources of protein available.
There are three main types of whey protein powder, concentrate (WPC), isolate (WPI), and hydrolysate (WPH).
Concentrate is the most common type, and is also the cheapest.
As a dietary supplement, whey protein is widely popular among bodybuilders, athletes, and others who want additional protein in their diet.
2. Whey Protein Promotes Muscle Growth
Muscle mass naturally declines with age.
This usually leads to fat gain and raises the risk of many chronic diseases.
However, this adverse change in body composition can be partly slowed, prevented, or reversed with a combination of strength training and adequate diet.
Particularly effective are high-quality protein sources, such as whey, which is rich in a branched-chain amino acid called leucine.
Leucine is the most growth-promoting (anabolic) of the amino acids (3Trusted Source).
For this reason, whey protein is effective for the prevention of age-related muscle loss, as well as for improved strength and a better-looking body (2Trusted Source).
However, unless your diet is already lacking in protein, supplements probably won’t make a big difference.
3. Whey Protein May Lower Blood Pressure
Abnormally high blood pressure (hypertension) is one of the leading risk factors for heart disease.
In whey proteins, the ACE-inhibitors are called lactokinins (14Trusted Source). Several animal studies have demonstrated their beneficial effects on blood pressure (15Trusted Source, 16Trusted Source).
A limited number of human studies have investigated the effect of whey proteins on blood pressure, and many experts consider the evidence to be inconclusive.
One study in overweight individuals showed that whey protein supplementation, 54 g/day for 12 weeks, lowered systolic blood pressure by 4%. Other milk proteins (casein) had similar effects (17Trusted Source).
This is supported by another study that found significant effects when participants were given whey protein concentrate (22 g/day) for 6 weeks.
However, blood pressure decreased only in those that had high or slightly elevated blood pressure to begin with (18).
No significant effects on blood pressure were detected in a study that used much lower amounts of whey protein (less than 3.25 g/day) mixed in a milk drink (19Trusted Source).
4. Whey Protein May Help Treat Type 2 Diabetes
Type 2 diabetes is a chronic disease characterized by high blood sugar and impaired function of insulin.
Insulin is a hormone that is supposed to stimulate the uptake of blood sugar into cells, keeping it within healthy limits.
Whey protein has been found to be effective at moderating blood sugar, increasing both the levels of insulin and the sensitivity to its effects (17Trusted Source, 20Trusted Source, 21Trusted Source, 22Trusted Source).
These properties of whey protein may even be comparable to those of diabetic drugs, such as sulfonylurea (25Trusted Source).
As a result, whey protein can be effectively used as a supplementary treatment for type 2 diabetes.
Taking a whey protein supplement before or with a high-carb meal has been shown to moderate blood sugar in both healthy people and type 2 diabetics (20Trusted Source).
5. Whey Protein May Help Reduce Inflammation
Inflammation is part of the body’s response to damage. Short-term inflammation is beneficial, but under certain circumstances it may become chronic.
Chronic inflammation can be harmful, and is a risk factor for many diseases. It may reflect underlying health problems or bad lifestyle habits.
A large review study found that high doses of whey protein supplements significantly reduced C-reactive protein (CRP), a key marker of inflammation in the body (26Trusted Source)
6. Whey Protein May Be Beneficial for Inflammatory Bowel Disease
Inflammatory bowel disease is a condition characterized by chronic inflammation in the lining of the digestive tract.
It is a collective term for Crohn’s disease and ulcerative colitis.
However, the available evidence is weak and further studies are needed before any strong claims can be made.
7. Whey Protein May Enhance the Body’s Antioxidant Defenses
Antioxidants are substances that act against oxidation in the body, reducing oxidative stress and cutting the risk of various chronic diseases.
One of the most important antioxidants in humans is glutathione.
Unlike most antioxidants we get from the diet, glutathione is produced by the body.
In the body, glutathione production depends on the supply of several amino acids, such as cysteine, which is sometimes of limited supply.
A number of studies in both humans and rodents have found that whey proteins may reduce oxidative stress and increase levels of glutathione (30Trusted Source, 31Trusted Source, 32Trusted Source, 33Trusted Source).
8. Whey Protein May Have Beneficial Effects on Blood Fats
High cholesterol, especially LDL cholesterol, is a risk factor for heart disease.
In one study in overweight individuals, 54 grams of whey protein per day, for 12 weeks, led to a significant reduction in total and LDL (the “bad”) cholesterol (17Trusted Source).
9. Whey Protein is Highly Satiating (Filling), Which May Help Reduce Hunger
Satiety is a term used to describe the feeling of fullness we experience after eating a meal.
It is the opposite of appetite and hunger, and should suppress cravings for food and the desire to eat.
Protein is by far the most filling of the three macronutrients (35Trusted Source).
These properties make it particularly useful for those who need to eat fewer calories and lose weight.
10. Whey Protein Can Help You Lose Weight
- Suppressing appetite, leading to reduced calorie intake (35Trusted Source).
- Boosting metabolism, helping you burn more calories (41Trusted Source, 42Trusted Source).
- Helping to maintain muscle mass when losing weight (43Trusted Source).
Whey protein has been shown to be particularly effective, and may have a superior effect on fat burning and satiety compared to other protein types (17Trusted Source, 36Trusted Source, 37Trusted Source, 44Trusted Source, 45Trusted Source).
Side Effects, Dosage, and How to Use It
Whey protein is very easy to incorporate into the diet.
25-50 grams per day (1-2 scoops) is a commonly recommended dosage, but make sure to follow the dosage instructions on the packaging.
Keep in mind that taking too much protein is useless. The body can only utilize a limited amount of protein at a given time.
Excessive consumption may also cause digestive problems, such as nausea, pain, bloating, cramping, flatulence, and diarrhea.
However, moderate consumption of whey protein supplements is well tolerated by most people, with a few exceptions.
If you are lactose intolerant, whey protein hydrolysate or isolate may be more suitable than concentrate. If you have ever had liver or kidney problems, then consult with a doctor before taking a protein supplement.
At the end of the day, whey protein is not just a convenient way to boost your protein intake, it may have some powerful health benefits as well.