Vegetable proteins have got much lower biological value compared to whey protein, egg or caseins. However, they are relatively popular, especially among vegetarians and vegans. Soy protein - as they are leading plant proteins - contain all the essential amino acids and are relatively cheap. Note, however, that with the soy protein supplementation it is advisable to add minerals such as calcium, magnesium, iron and zinc to the diet, as their absorption may be impaired. Using of vegetable proteins is also associated with providing to the body some kinds of estrogen, which, especially for men, may interfere the production of androgens.