Tanning and Vitamin D - Holick

[stan@sunsys]

American Journal of Clinical Nutrition, Vol. 80, No. 6, 1645-1649, December 2004
© 2004 American Society for Clinical Nutrition




Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density1,2,3

Vin Tangpricha, Adrian Turner, Catherine Spina, Sheila Decastro, Tai C Chen and Michael F Holick



1 From the Vitamin D, Skin and Bone Research Laboratory (AT, CS, SD, TCC, and MFH) and the Section of Endocrinology, Diabetes and Nutrition (AT, KS, SD, TCC, and MFH), Department of Medicine, Boston University School of Medicine, Boston, and the Section of Endocrinology, Metabolism and Lipids and the Department of Medicine, Emory University School of Medicine, Atlanta (VT)



Background: Vitamin D is made in the skin on exposure to solar radiation, and it is necessary to optimal skeletal health. Subjects who use a tanning bed that emits ultraviolet B radiation (290–315 nm) are likely to have higher 25-hydroxyvitamin D [25(OH)D] concentrations than do subjects who do not regularly use a tanning bed.

Objective: The first objective of this study was to ascertain whether subjects who regularly use a tanning bed have higher 25(OH)D concentrations than do subjects who do not use a tanning bed. The second objective was to ascertain whether higher 25(OH)D concentrations correlated positively with bone mineral density.

Design: This cross-sectional analysis examined 50 subjects who used a tanning bed at least once a week and 106 control subjects. Each subject gave a blood specimen for measurement of serum 25(OH)D and parathyroid hormone concentrations. Each subject underwent bone mineral density testing of the hip and spine.

Results: Subjects who used a tanning bed had serum 25(OH)D concentrations 90% higher than those of control subjects (115.5 ± 8.0 and 60.3 ± 3.0 nmol/L, respectively; P < 0.001). Subjects who used a tanning bed had parathyroid hormone concentrations 18% lower than those of control subjects (21.4 ± 1.0 and 25.3 ± 0.8 pg/mL, respectively; P = 0.01). Tanners had significantly higher BMD and z scores at the total hip than did nontanners. 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.