Amavithamini ayizici ezibalulekile zokulondoloza impilo nempilo.Kuyinto ebalulekile ukuze izinja zigcine ukuphila, zikhule futhi zithuthuke, zigcine imisebenzi evamile yomzimba kanye ne-metabolism.Amavithamini awabalulekile kangako ekudleni kwezinja kunamaprotheni, amafutha, ama-carbohydrate namaminerali.Nakuba amavithamini engewona umthombo wamandla futhi engeyona into eyinhloko eyakha izicubu zomzimba, indima yawo isezicini zazo zemvelo.Amanye amavithamini ayizingqimba zama-enzyme;amanye anjenge-thiamine, i-riboflavin, ne-niacin akha ama-coenzymes kanye namanye.Lawa ma-enzyme kanye nama-coenzymes abandakanyeka enqubweni yokusabela kwamakhemikhali ezinqubweni ezihlukahlukene ze-metabolic yenja.Ngakho-ke, idlala indima ebaluleke kakhulu kumetabolism yamaprotheni, amafutha, ama-carbohydrate, usawoti wezinto ezingaphili nezinye izinto emzimbeni.