25hydroxyvitamin D blood levels need to be 65-90ng/mls
Moan, who worked with Richard Setlow, a biophysicist at Brookhaven National Laboratory in New York state, said vitamin D deficiency could be lethal. Research links it with heart disease, diabetes, arthritis and reduced immunity.
Their research says: “Cold climates and high latitudes would speed up the need for skin lightening. Agricultural food was an insufficient source of vitamin D, and solar radiation was too low to produce enough vitamin D in dark skin.”
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