Buckwheat (Fagopyrum esculentum), a cultivated plant of the knotweed family, its food the raw material is dried grain, and a medicinal – herb of buckwheat (Herba Fagopyri esculenti), which are the source of active substances: flavonoids (including 5% rutin and quercetin), minerals (I.e. al. zinc, manganese, copper), organic acids and D-chiro-inositol (increasing insulin sensitivity in tissues). Flavonoids present in herbs and powdered grains reduce cholesterol in the blood and affect the condition of the circulatory system and nervous system. The raw material also stimulates the secretion of urine. Powdered buckwheat is a component of nutritional supplements for physically active people.