Though classed as a vitamin, vitamin D is equally akin to the definition used to describe hormones. It is produced by the action of sunlight upon the skin, from where it is processed by the kidneys and liver into an extremely powerful substance.
Deficiency famously results in rickets in children and osteomalacia (bone calcium loss) in adults. Elderly people in nursing homes are most at risk, with joint pain accompanying the reduction in bone density.
Natures Aid Vitamin D tablet contains 10mcg (400iu) or 25mcg (1000iu) of Vitamin D.
Per Tablet Amount %ECRDA
Vitamin D3 25µg (1000iu) 500
ECRDA = EC Recommended Daily Allowance
Vitamin D is a group of fat-soluble pro-hormones, with the two major forms being Vitamin D2 (ergocalciferol) and Vitamin D3 (cholecalciferol). Vitamin D3 is produced in the skin when exposed to UVB radiation from sunlight and is the most active form of the two.
Due to the rapid bone growth in children, their daily requirements are much the same as adults’. Common food sources include cold water fish, butter and egg yolks.
Vitamin D has the greatest potential for toxicity of all the vitamins, though amounts up to 1000mcg are generally agreed to be safe in adults. Younger adults or children may supplement up to 400iu daily. Vitamin D is theoretically contraindicated while taking warfarin (albeit no case of increased bleeding has ever been reported) and verapamil medications. Oestrogen-based hormone medications may increase blood levels of vitamin D (and hence improve bone density), but also cause a fall in the beneficial HDL cholesterol.