Vitamin D Deficiency and Safe Supplementation

The body’s ability to metabolize vitamin declines with age, as does the ability of the skin to produce vitamin D3. Supplementation may also help reduce the risk of falls and therefore fractures.

Dosage and safe prescribing

Optimal blood levels of vitamin D are between 30–60 ng/mL. Suggested supplementation is normally 1000IU of D3 per day, depending on current blood status. Vitamin D occurs in two forms; cholecalciferol (D3) is produced by the action of sunlight on skin and is also found in animals and fish (e.g. cod-liver oil); and ergocalciferol (D2) is found in a very limited range of foods. When taken as a supplement, D3 is regarded as the most important dietary form and is identical to the form produced in the body, whereas D2 is a synthetic form found often in inferior supplements.