He also pointed out that ricketts, a disease caused by vitamin D deficiency, has virtually disappeared in recent years, while Crohn's has soared.

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Attempts have been made to correlate other disease states with the relative deficiency in vitamin D that is still common in high latitudes.

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Not only can this lead to an increased risk of fractures and osteoporosis in general, but vitamin D deficiency has also been cited as a contributor to increased rates of diabetes, cancer, and cardiovascular disease among African-Americans.

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