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

Aim: To investigate whether daily subliminal ultraviolet-B irradiation in elderly subjects can maintain a normal vitamin D status.

Material And Methods: 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.

Results: 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.

Conclusions: 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.