Vitamin D yɛ secosteroids kuo bi a ɛtumi nwura sradeɛ mu a ɛma 'calcium', 'magnesium', ne 'phosphate' twetwe dwonsɔtwaa mu kɔ soro, na ɛma abɔdeɛ mu nsunsuansoɔ foforɔ pii ba. Wɔ nnipa mu no, nnuru a ɛho hia paa wɔ saa kuo yi mu ne vitamin D3 (cholecalciferol) ne vitamin D2 (ergocalciferol). Wobetumi anom cholecalciferol ne ergocalciferol afi aduane ne nnuru a wɔde ka ho no mu. Nnuane kakraa bi pɛ, te sɛ mpataa a sradeɛ wɔ mu no vitamin D pii na ahyɛ mu ma. Wɔ U.S. ne aman afoforɔ mu no, wɔde vitamin D ahyɛ nantwi nufusuo ne nufusuo a wonya fi afifide mu a wɔde si ananmu no mu den, te sɛ aburo aduane pii a yɛdi no anɔpa.