Subliminal ultraviolet-B irradiation for the prevention of vitamin D deficiency in the elderly: a feasibility study.

Abstract

To investigate whether daily subliminal ultraviolet-B irradiation in elderly subjects can maintain a normal vitamin D status. In an open, uncontrolled study, 10 residents (four men and six women), mean age on entry of 83 years (range 65-97 years), from a residential nursing home in County Durham, England, were exposed daily to an artificial source of ultraviolet-B radiation equivalent to 15 min of summer sunshine. The change in plasma 25-hydroxyvitamin D levels following irradiation was measured. Improvement in the vitamin D status of the elderly residents was achieved with no change in their routine and with no intervention on the part of carers. On the basis of this small pilot study we conclude that subliminal ultraviolet-B irradiation may be effective in maintaining vitamin D status in elderly people at a lower cost than that of using oral vitamin D supplementation. Further controlled studies are needed before this technique can be recommended to change health policy with regard to the vitamin D status of institutionalised elderly people.