"What is unnatural is restricting sunshine and wearing chemicals that refract healthy sunshine. It IS natural to walk around in our birthday suits but we can't do that eaither. Even if we could walk around naked, that would be useless if you live in, say, Ohio, especially if you' black.2

Fortunately everything you've said is incorrect 'Sunscreen can reduce vitamin D production, but probably not enough to have a significant effect.'

'Clinically prescribed sunscreen (sun protection factor 15) does not decrease serum vitamin D concentration sufficiently either to induce changes in parathyroid function or in metabolic markers.'
http://www.ncbi.nlm.nih.gov/pubmed/...Pubmed_RVDocSum
09


Vitamin D and homeostasis
http://evoandproud.blogspot.com/200...omeostasis.html

" Matsuoka et al. (1991) demonstrated that after single-dose, whole-body UVB exposure black subjects had distinctly lower serum vitamin D3 levels than whites, but differences between the two groups narrowed after liver hydroxylation to 25-OHD and disappeared after kidney hydroxylation to 1,25-(OH)2D. These findings suggest that there is a compensatory mechanism whereby, in the presence of vitamin D3 suppression by melanin, the liver and kidney hydroxylating enzymes are activated in tandem to ensure that the concentration of the biologically active 1,25-(OH)2D metabolite is normalized and kept constant regardless of ethnic pigmentation (Matsuoka et al., 1991, 1995).


Robins (2009) goes on to note that nearly half of all African Americans are vitamin-D deficient but show no signs of calcium deficiency. Indeed, they “have a lower prevalence of osteoporosis, a lower incidence of fractures and a higher bone mineral density than white Americans, who generally exhibit a much more favourable vitamin D status.” He also cites a survey of 232 black (East African) immigrant children in Melbourne, Australia, among whom 87% had levels below 50 nmol/L and 44% below 25 nmol/L. None had rickets (McGillivray et al., 2007)."