Whey protein as a dietary supplement
Whey protein is a natural dietary supplement derived from milk, specifically the liquid leftover after cheese production. It is recognized for its rich content of amino acids, particularly cysteine, which is crucial for the body's production of glutathione, a powerful antioxidant. This has led to its proposed use in various health contexts, including support for conditions like cancer, diabetes, and human immunodeficiency virus (HIV) infection. While whey protein is known to enhance muscle mass, especially when combined with resistance training, evidence suggests it may not be significantly more effective than other protein sources, such as casein.
Additionally, whey protein has been studied for potential benefits in mental function, weight management, and cardiovascular health, with some findings indicating it may help regulate insulin levels and lower cholesterol. However, despite these promising areas of research, definitive evidence linking whey protein consumption to improved health outcomes remains limited. It is generally considered safe for the majority of people, though individuals with milk allergies should exercise caution. Overall, whey protein serves as a versatile supplement, but its health benefits require further investigation to substantiate many of the claims associated with its use.
Whey protein as a dietary supplement
DEFINITION: Natural substance promoted as a dietary supplement for specific health benefits.
PRINCIPAL PROPOSED USE: Raising glutathione levels
OTHER PROPOSED USES: Cancer treatment support, cataracts, diabetes, human immunodeficiency virus infection, mental function enhancement, sports performance enhancement, viral hepatitis, weight support, antioxidant, blood sugar control, lowering blood pressure and cholesterol, bone health
Overview
Whey is one of the two major classes of protein in milk. The other is casein, the “curds” of “curds and whey.” Proteins are made of amino acids, and whey contains high levels of the amino acid cysteine. This is the basis for many of its proposed uses. It also contains branched-chain amino acids (BCAAs). However, while there is no question that whey is a highly digestible and rich protein source, there is emerging supporting evidence that it provides any specific health benefits.
Sources
When milk is converted into cheese, whey is the liquid left behind. There is no specific dietary requirement for whey because the amino acids it contains are present in a wide variety of other foods, too.
Therapeutic Doses
A typical dose of whey protein is 20 to 30 grams per day.
Therapeutic Uses
Many studies look into the therapeutic uses of whey protein. There is some evidence that whey can raise levels of glutathione. Glutathione is an antioxidant that the body manufactures to defend itself against free radicals. In certain diseases, glutathione levels may fall to below-normal levels. These conditions include cataracts, human immunodeficiency virus (HIV) infection, liver disease, diabetes, and various types of cancer. This reduction of glutathione might contribute to the disease's symptoms or progression.
To solve this problem, glutathione supplements have been recommended, but glutathione is essentially not absorbed when it is taken by mouth. Whey protein may be a better solution. The body uses cysteine to make glutathione; whey is rich in cysteine. Meaningful preliminary evidence suggests that whey can raise glutathione levels in people with cancer, hepatitis, or HIV infection. However, while these are promising findings, one essential piece of evidence is lacking: There is no evidence that this rise in glutathione produces any meaningful health benefits.
Whey protein has also been proposed as a bodybuilding aid, partly because of its high content of BCAAs. There is evidence that whey protein helps accelerate muscle mass development. Several studies have shown that whey protein, when combined with resistance training, increased muscle mass. However, there is little evidence that whey protein is more effective for this purpose than any other protein. For example, one small double-blind study found evidence that both casein and whey protein were more effective than placebo at promoting muscle growth after exercise, but whey was no more effective than the far less expensive casein. However, a single small study did find ergogenic benefits with whey compared with casein.
One study looked at whether whey protein could help women with HIV build muscle mass. Study participants were divided into three groups: those who undertook a course of resistance exercise (weight lifting), those who took whey, and those who did both. Resistance exercise alone was just as effective as resistance exercise plus whey, while whey alone was not effective.
Whey contains alpha-lactalbumin, a protein that contains high levels of the amino acid tryptophan. Tryptophan is the body’s precursor to serotonin and is thought to affect mental function. In a small double-blind study, the use of alpha-lactalbumin in the evening improved morning alertness, perhaps by enhancing sleep quality. Another small double-blind study found weak evidence that alpha-lactalbumin improved mental function in people sensitive to stress. A third study failed to find that alpha-lactalbumin significantly improved memory in women experiencing premenstrual symptoms.
Weak evidence hints that whey might help prevent cancer or augment the effectiveness of cancer treatment. Infant formula based on predigested (hydrolyzed) whey protein is somewhat less allergenic than standard infant formula; this might reduce symptoms of colic and possibly decrease the risk that the infant will later develop allergies.
Many other studies have been conducted on the effectiveness and health benefits of whey protein. Studies have shown participants consuming whey protein consumed less food than those given a placebo. Whey protein provides a level of satiety that may make it valuable for weight management. Other studies have indicated whey protein may help regulate insulin and lower cholesterol and blood pressure. This suggests benefits for diabetes patients and people concerned with cardiovascular health. Finally, limited studies suggest that whey protein may increase bone density, reducing the risk of osteoporosis in post-menopausal women.
Safety Issues
As a constituent of milk, whey protein is presumed to be a safe substance. People with allergies to milk, however, are likely to be allergic to whey (even to partially hydrolyzed forms of whey).
Bibliography
Agin, D., et al. "Effects of Whey Protein and Resistance Exercise on Body Cell Mass, Muscle Strength, and Quality of Life in Women with Human Immunodeficiency Virus." AIDS, vol. 15, 2001, pp. 2431-2440.
Borsheim, E., et al. "Effect of an Amino Acid, Protein, and Carbohydrate Mixture on Net Muscle Protein Balance After Resistance Exercise." International Journal of Sport Nutrition and Exercise Metabolism, vol. 14, 2004, pp. 255-271.
Chromiak, J. A., et al. "Effect of a Ten-Week Strength Training Program and Recovery Drink on Body Composition, Muscular Strength and Endurance, and Anaerobic Power and Capacity." Nutrition, vol. 20, 2004, pp. 420-427.
Luhovyy, Bohdan L., et al. "Whey Proteins in the Regulation of Food Intake and Satiety." Journal of the American College of Nutrition, vol. 26, no. 6, 2007, pp. 704S-12S, doi.org/10.1080/07315724.2007.10719651. Accessed 15 Sept. 2024.
Markus, C. R., et al. "Evening Intake of Alpha-Lactalbumin Increases Plasma Tryptophan Availability and Improves Morning Alertness and Brain Measures of Attention." American Journal of Clinical Nutrition, vol. 81, 2005, pp. 1026-1033.
Marshall, K. "Therapeutic Applications of Whey Protein." Alternative Medicine Review, vol. 9, 2004, pp. 136-156.
Micke, P., et al. "Effects of Long-Term Supplementation with Whey Proteins on Plasma Glutathione Levels of HIV-Infected Patients." European Journal of Nutrition, vol. 41, 2002, pp. 12-18.
Olsen, Natalie, and Joseph Nordqvist. "What are the benefits and risks of whey protein?" Medical News Today, 25 Oct. 2023, www.medicalnewstoday.com/articles/263371. Accessed 15 Sept. 2024.
Szajewska, H., et al. "Extensively and Partially Hydrolysed Preterm Formulas in the Prevention of Allergic Diseases in Preterm Infants." Acta Paediatrica, vol. 93, 2004, pp. 1159-1165.