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White Europeans could have evolved as recently as 5,500 years ago, according to research which suggests that the early humans who populated Britain and Scandinavia had dark skins for millenniums. It was only when early humans gave up hunter-gathering and switched to farming about 5,500 years ago that white skin began to be favoured, say the researchers. This is because farmed food was deficient in vitamin D, a vital nutrient. Humans can make this in their skin when exposed to sunlight, but dark skin is much less efficient at it.

Robert P. Heaney is John A. Creighton University Professor, Creighton University, Omaha, Nebraska, United States. Hominid evolution took place in an environment (equatorial East Africa) that provided a superabundance of both calcium and vitamin D, the first in available foods and the second through conversion of 7-dehydrocholesterol to pre-vitamin D in the skin, a reaction catalysed by the intense solar ultraviolet (UV) radiation. Seemingly as a consequence, the evolving human physiology incorporated provisions to prevent the potential of toxic excesses of both nutrients. For vitamin D the protection was of two sorts: skin pigmentation absorbed the critical UV wavelengths and thereby limited dermal synthesis of cholecalciferol; and slow delivery of vitamin D from the skin into the bloodstream left surplus vitamin in the skin, where continuing sun exposure led to its photolytic degradation to inert compounds. For calcium, the adaptation consisted of very inefficient calcium absorption, together with poor to absent systemic conservation. The latter is reflected in unregulated dermal calcium losses, a high sensitivity of renal obligatory calcium loss to other nutrients in the diet and relatively high quantities of calcium in the digestive secretions. Today, chimpanzees in the original hominid habitat have diets with calcium nutrient densities in the range of 2 to 2.5 mmol per 100 kcal, and hunter-gatherer humans in Africa, South America and New Guinea still have diets very nearly as high in calcium (1.75 to 2 mmol per 100 kcal) (Eaton and Nelson, 1991). With energy expenditure of 3 000 kcal per day (a fairly conservative estimate for a contemporary human doing physical work), such diets would provide substantially in excess of 50 mmol of calcium per day. By contrast, median intake in women in North America and in many European countries today is under 15 mmol per day. Two factors altered the primitive situation: the migration of humans from Africa to higher latitude

"Last Wednesday night I gave a lecture to my clients on hunter-gatherer diets. The turnout was great and the information was well-received. I had it professionally video-recorded and will probably offer this as a DVD for sale (with the handout included). Watch for it in the future. Part of what I discussed was vitamin D3 supplementation. Since I have been supplementing with 4,000-10,000 Units of D3 per day I have noted enhanced recovery and size response from my training. Apparently, skeletal muscle has both surface receptors and nuclear receptors for D3 that augment calcium flux during contraction (from surface receptors) and have steroid-like effects at the nuclear level WRT protein synthesis. This D3 supplementation is not really "supplementation" but is instead "augmentation" to levels that would be normal if we got normal sun exposure as we did in our evolutionary past. Check out www.vitamindcouncil.org for more information. Also, check out this abstract below for your consideration. Also, check out this article."

The American diet circa 2007 is a disaster - but positive change has begun. Those were the twin themes of the "Fourth Annual Nutrition and Health Conference" held in San Diego, Calif., May 14-16, 2007. The conference was sponsored by the University of Arizona's College of Medicine in conjunction with the Program in Integrative Medicine (PIM); PIM was founded and is co-directed by Dr. Weil. \n\nThe three-day event brought together leading nutrition researchers from around the world, bearing plenty of both bad and good news. Some highlights: