Dietary supplement of whey protein concentrate obtained by ultrafiltration and spray drying, with vitamins. Powder to be reconstituted with sweetener. Proteins contribute to the growth and maintenance of muscle mass, vitamin E to the protection of cells against oxidative stress and vitamins B1, B2 B6, B12 and biotin to normal energy metabolism, niacin, pantothenic acid and folic acid to the reduction of tiredness and fatigue.