Vitamin D, Tanning and All-cause Mortality
The Jersey Shore is a beautiful place especially in the summer. While grocery shopping this week, I was amazed to see 3 women with evidence of extreme sun exposure. While they may perceive themselves to be beautifully tanned, their skin appeared wrinkled and leathery. If not vanity, could they be pursuing extreme tanning for health reasons?
Low vitamin D status is associated with increased risk of premature death. Garland and colleagues report that people with serum 25(OH)D3 levels below 75 nmol/L have a 1.9 x greater risk of mortality than those above that concentration. They emphasize their findings confirm the IOM Dietary Reference Intakes for Calcium and Vitamin D report except that the cut-off for all-cause mortality reduction is 75 nmol/L rather than 50 nmol/L.
High serum 25(OH)D3 concentrations are correlated with reduced risk of mortality in women diagnosed with breast cancer. Based on a meta-analysis of 5 studies, Mohr and colleagues recommended that women with breast cancer should aim for vitamin D concentrations between 75 to 200 nmol/L.
Sun exposure, dietary supplement use, ethnicity and season are predictors of vitamin D status. Maybe the women in the New Jersey box store were being treated for breast cancer. However, it is important to balance vitamin D requirements and sun exposure. Tanning beds, sunburns, and total sun exposure increase the risk of melanoma.
Having too low-blood level of vitamin D is hazardous. Fortunately, vitamin D levels can be increased by dietary selections or supplementation. Dr Hofflich reminds the medical community and public that vitamin D is safe in doses up to 4,000 IU daily.
Garland CF, Kim JJ, Mohr SB, Gorham ED, Grant WB, Giovannucci EL, Baggerly L, Hofflich H, Ramsdell JW, Zeng K, Heaney RP. Meta-analysis of all-cause mortality according to serum 25-25hydroxyvitamin D. 2014 Am J Publ Health doi: 10.2105/AJPH.2014.302034
Mohr SB, Gorham ED, Kim J, Hofflich H, Garland CF. Meta-analysis of vitamin D sufficiency for improving survival of patients with breast cancer. 2014 Anticancer Res 34:1163-1166
George JA, Norris SA, van Deventer HE, Pettifor JM, Crowther NJ. Effect of adiposity, season, diet and calcium or vitamin D supplementation on the vitamin D status of healthy urban African and Asian-Indian adults. 2014 Br J Nutr doi: 10.1017/S0007114514001202