Last updated: August 27, 2020
Protein is an essential macronutrient that supports vital body processes and functions, including growth, nervous system development, muscle and bone structure, and physical performance. (10) Dietary protein is provided by a variety of animal and plant sources and is often consumed in the form of protein supplements.
Of the various protein supplements available, whey protein is one of the most easily digested and bioavailable protein sources. (8) Most commonly associated with sports nutrition, research shows that whey protein also has a variety of other possible applications in health. (8)
What is whey protein?
Whey protein is produced from the liquid portion of milk that is separated from the curds during cheese production. (12) Approximately 20% of the protein found in milk is whey, and the remainder is casein protein. (8) The composition of whey protein is primarily made up of various forms of smaller protein fragments that include:
- 45 to 57% β-lactoglobulin
- 15 to 25% α-lactalbumin
- 10 to 15% immunoglobulin
- 10 to 15% glycomacropeptide
- 10% bovine serum albumin
- Approximately 1% lactoferrin
- Less than 1% lactoperoxidase (1)
Whey protein contains all of the essential amino acids, which are released during digestion and contribute to the health effects of whey. (1)

Types of whey protein
Various processing methods are used to produce whey protein. Outlined below, are the types of whey protein and their nutritional compositions.
Whey protein powder
Whey powder contains a relatively low concentration of protein when compared to the other types. Whey powder is composed of approximately 11 to 14.5% protein, 63 to 75% lactose, and 1 to 1.5% fat. (8)
Whey protein concentrate
Whey protein concentrate (WPC) is whey that is processed to remove water, ash, lactose (milk sugars), and some mineral content. WPC generally contains 25 to 89% protein, 10 to 55% lactose, and 2 to 10% fat. (8)
Whey protein isolate
Considered to be the purest form of protein, whey protein isolate (WPI) is further concentrated to remove more lactose and fat from the whey. The composition of WPI is over 90% protein, with less than 1% each of lactose and fat. Due to low lactose content, some individuals who are lactose-intolerant may be able to tolerate WPI. It’s important to note that the manufacturing process of WPI denatures some of the protein content, changing its structure, which may impair the effectiveness of the final product. (8)
Whey protein hydrolysate
Also known as hydrolyzed whey protein, whey protein hydrolysate (WPH) undergoes hydrolysis, a process that releases peptides and amino acids. This mimics the hydrolysis that occurs during digestion and releases the active constituents of protein. This process improves the protein efficiency ratio and digestibility of the proteins. (1)
Daily protein requirements: where does whey fit in?
Current dietary guidelines for general health recommend a protein intake of 0.8 grams per kilogram of body weight per day. (5) For example, an individual that weighs 150 pounds (68 kg) should consume approximately 54 grams of protein per day. Greater protein intake may be beneficial or required for various reasons, such as increased physical activity levels, weight loss, and sarcopenia (muscle tissue loss during aging). (7)(8) Whey protein supplements commonly contain 20 to 40 grams of protein per serving. (7)

Whey protein benefits
Protein is composed of amino acids, which are used as structural components in the body to produce enzymes, hemoglobin, hormones, and tissues such as muscle. Although glucose is the body’s primary energy source, in some cases the body may also use protein for energy. (8) There are several evidence-based health benefits of whey protein supplementation, including supporting immune health, metabolic health, and athletic performance and recovery, as well as addressing sarcopenia and managing weight. (2)(3)(4)(7)(11)
Improves athletic performance and recovery
Whey protein is commonly used to support exercise performance and recovery. Various trials in physically active males and females have compared the effects of whey protein supplementation to a calorie-matched carbohydrate drink post-exercise. (13)(4) The findings suggest that whey supplementation following intense exercise may help improve muscle function recovery, reduce exercise-induced muscle damage, and increase protein balance in the body. (4)(13)
Being physically active generally increases your protein requirements. The International Society of Sports Nutrition (ISSN) recommends a daily protein intake of 1.4 to 2 grams of protein per kilogram of body weight for active individuals trying to build or maintain muscle mass. (9)
Supports immune health
Bovine (cow) milk products, including whey, provide compounds with anti-microbial and immunomodulatory effects. (11) Bovine immunoglobulins, which make up 10 to 15% of whey protein, can support the immune system’s response to pathogenic viruses, bacteria, and allergens. (1)(11) A review article shows that bovine immunoglobulins may prevent upper respiratory tract and gastrointestinal tract infections. (11)
Promotes metabolic health
Whey protein may help prevent metabolic syndrome, a group of metabolic disorders that can increase your risk of chronic diseases, including cardiovascular disease and type 2 diabetes. A systematic review of 2,344 overweight and obese individuals found that whey supplementation was associated with reduced systolic blood pressure, diastolic blood pressure, waist circumference, triglyceride levels, and fasting blood glucose when compared to controls. (2)
Supports muscles in sarcopenia
Sarcopenia is a condition characterized by a significant decline in muscle mass and function, particularly affecting gait speed (the speed at which you can walk a certain distance). Sarcopenia affects approximately 10% of adults over the age of 60, and can impair an individual’s independence and ability to conduct daily activities. A review of studies in older adults demonstrated that whey protein supplementation may improve biomarkers of sarcopenia, such as muscle mass index, handgrip strength, gait speed, and insulin-like growth factor 1 (IGF-1), a hormone involved in muscle protein synthesis. (7)
Aids weight management
Higher protein intake may support weight loss by increasing satiety. A randomized controlled trial of overweight and obese individuals compared the effects of long-term (23-week) supplementation of whey protein, soy protein, and carbohydrate beverages, each containing the same caloric content. Following the intervention, body weight and fat mass were lower in the whey protein group than the carbohydrate group, but didn’t differ from the soy protein group. Compared to the two other groups, individuals consuming whey protein had smaller waist circumference and lower fasting ghrelin levels, a hormone involved in stimulating appetite. (3) Note that excess protein consumption may also lead to weight gain or metabolic burden on certain organs, so it’s always best to consult with an integrative healthcare provider to ensure you are consuming the optimal amount of protein. (6)
The bottom line
Supplementing with whey protein can help you meet your daily protein requirements and provide additional health benefits. If you’re a patient, consult with your integrative healthcare practitioner to determine if whey protein is right for you.
- Adams, R. L., & Broughton, K. S. (2016). Insulinotropic effects of whey: Mechanisms of action, recent clinical trials, and clinical applications. Annals of Nutrition and Metabolism, 69(1), 56–63.
- Badely, M., Sepandi, M., Samadi, M., Parastouei, K., & Taghdir, M. (2019). The effect of whey protein on the components of metabolic syndrome in overweight and obese individuals; A systematic review and meta-analysis. Diabetes & Metabolic Syndrome: Clinical Research & Reviews, 13(6), 3121–3131.
- Baer, D. J., Stote, K. S., Paul, D. R., Harris, G. K., Rumpler, W. V., & Clevidence, B. A. (2011). Whey protein but not soy protein supplementation alters body weight and composition in free-living overweight and obese adults. The Journal of Nutrition, 141(8), 1489–1494.
- Brown, M. A., Stevenson, E. J., & Howatson, G. (2018). Whey protein hydrolysate supplementation accelerates recovery from exercise-induced muscle damage in females. Applied Physiology, Nutrition, and Metabolism, 43(4), 324–330.
- Cintineo, H. P., Arent, M. A., Antonio, J., & Arent, S. M. (2018). Effects of protein supplementation on performance and recovery in resistance and endurance training. Frontiers in Nutrition, 5, 83.
- Delimaris, I. (2013). Adverse effects associated with protein intake above the recommended dietary allowance for adults. ISRN Nutrition, 2013, 1–6.
- Gilmartin, S., O’Brien, N., & Giblin, L. (2020). Whey for sarcopenia; Can whey peptides, hydrolysates or proteins play a beneficial role? Foods, 9(6), 750.
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- Kårlund, A., Gómez-Gallego, C., Turpeinen, A. M., Palo-oja, O.-M., El-Nezami, H., & Kolehmainen, M. (2019). Protein supplements and their relation with nutrition, microbiota composition and health: Is more protein always better for sportspeople? Nutrients, 11(4), 829.
- Ulfman, L. H., Leusen, J. H. W., Savelkoul, H. F. J., Warner, J. O., & van Neerven, R. J. J. (2018). Effects of bovine immunoglobulins on immune function, allergy, and infection. Frontiers in Nutrition, 5, 52.
- U.S. National Library of Medicine. (2020, August 4). Whey protein. Retrieved from https://medlineplus.gov/druginfo/natural/833.html
- West, D., Abou Sawan, S., Mazzulla, M., Williamson, E., & Moore, D. (2017). Whey protein supplementation enhances whole body protein metabolism and performance recovery after resistance exercise: A double-blind crossover study. Nutrients, 9(7), 735.