Tanning is associated with optimal vitamin D status
(serum 25-hydroxyvitamin D concentration) and higher bone mineral
density.
http://www.msrc.co.uk/index.cfm?fuseaction=show&pageid=989
Vitamin D, Skin and Bone Research Laboratory and the Section
of Endocrinology, Diabetes and Nutrition, Department of Medicine,
Boston University School of Medicine, Boston, MA 02118, USA.
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.
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