Tanning is associated with optimal vitamin D status

 Conclusion: The regular use of a tanning bed that emits vitamin D–producing ultraviolet radiation is associated with higher 25(OH)D concentrations and thus may have a benefit for the skeleton. Am J Clin Nutr 2004;80:1645–9.

The use of tanning beds has been promoted to the public for the cosmetic purpose of tanning, but this study shows that a moderate use of tanning beds may also provide some medical benefit.

Higher concentrations of 25(OH)D throughout the year may have a significant effect in enhancing intestinal calcium absorption and improving bone health (7, 8, 42). Blood concentrations of 25(OH)D in tanners are  75 nmol/L, which is considered to be necessary for maximum intestinal calcium transport (23, 42).

This may explain why higher serum 25(OH)D concentrations are associated with higher bone density. There is mounting evidence that a healthy concentration of 25(OH)D (ie, 75 nmol/L) may reduce the risk of colon, breast, and prostate cancers, hypertension,
and autoimmune diseases (2, 3, 39–42).

In conclusion, the regular use of a tanning bed results in higher 25(OH)D concentrations and prevents increased seasonal prevalence of vitamin D deficiency during the winter.

The subjects who had used tanning beds for a mean of5 y had higher BMD
at the hip than did the nontanners (control subjects). Larger studies should be conducted to investigate the potential positive effect of chronic use of tanning beds on vitamin D status and bone health.

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