N'ihe d? ka mmalite af? 1930, nd? ?kà mm?ta sayens? ch?p?tara na ikpughe ìhè anyanw? ma ? b? ??? mman? oliv, mman? flaxseed, na ihe oriri nd? ?z? nke UV nwere ike ?l?so ?kp?kp? ?kp?kp? ?g?. Nchoputa ozo nke ndi sayensi choputara ma kpo aha vitamin D dika ihe na-aru oru n'ime ahu mmadu maka ibuso osteoporosis agha.

Vitamin D (VD maka nkenke) b? vitamin soluble ab?ba, nke b? otu ?d? steroid nwere mmet?ta mgbochi rickets na ihe nd? yiri ya. Nd? kachas? mkpa b? vitamin D3 (cholecalciferol, cholecalciferol) na vitamin D2 (calciferol). Vitamin D na nri tumadi na-ab?a site na an?man? dabeere nri d? ka imeju az?, nkochi ime akwa, b?ta, wdg. Mgbe ? ris?r? nri, ? na-etinye obi g? dum na obere eriri af? n'ihu bile na ebuga n'ime ?bara n'?d? chylomicrons. A na-agbanwe ya n'ime 1,25-dihydroxyvitamin D3 site na imeju, ak?r?, na mitochondrial hydroxylase, nke nwere ?r? ndu ma nwee ike kpalie njik? nke protein na-ejik?ta calcium (CaBP) na mucosa intestinal, na-akwalite absorption calcium, ma kwalite ?kp?kp? ?kp?kp?. A na-echekwa 7-dehydrocholesterol, k?lestr?l sitere na ah? mmad?, na-echekwa ya n'okpuru akp?kp? an? ma nwee ike gbanwee ya ka ? b?r? cholecalciferol n'okpuru ìhè anyanw? ma ? b? radieshon ultraviolet. ? b? vitamin D nke na-akwalite nnabata nke calcium na phosphorus.

VD b? ihe mmep?ta nke steroid. ? b? kristal na-acha ?cha, soluble na ab?ba, nke nwere ihe kw?siri ike, nguzogide okpom?k? d? elu, antioxidant, ? b?gh? ihe na-eguzogide acid na alkali, ma nwee ike ibibi ya site na ire ere ab?ba ab?ba. Imeju ?m? an?man?, mman? imeju az?, na nkochi imeju akwa nwere ?bara ?d?naya. Ihe a ch?r? kwa ?b?ch? maka ?m? ?h?r?, ?m?aka, nd? n? n'af? iri na ?ma, nd? inyom d? ime na nd? nne na-enye nwa ara b? 400 IU (ngalaba mba ?wa). Mgbe enweghi, nd? okenye na-enwekar? osteomalacia, na ?m?aka na-enwekar? rickets. ? b?r? na calcium ?bara na-ebelata, enwere ike ?nwe aka na ?kw?, mgbakas? ah?, wdg, nke na-emet?takwa mmepe nke ezé. Iri oke vitamin D nwere ike ime ka calcium ?bara d? elu, enwegh? ag??, vomiting, af? ?s?sa, na ?b?na ectopic ossification nke an? ah? d? nro.