The best known effects of whey protein are its ability to help promote weight loss, increase lean muscle mass and boost the immune system.

Whey protein contains high levels of essential and branched-chain amino acids which have been shown to help people maintain or build muscle tissue. This can be important for athletes, people trying to lose body fat and older adults concerned about maintaining their muscle mass. Whey protein may also help with weight loss by increasing feelings of fullness and maintaining blood glucose at constant levels.

Whey proteins boost the immune system by helping the body produce an antioxidant called glutathione. Glutathione protects against free radical damage, pollution, toxins, infection and sunlight exposure. Adding whey protein to the diet may help protect health in people of all ages.