Saturday, July 3, 2010

Ridicules slow level of vitamin D in supplements compared to sunlight

There is a term in vitamin D research called a MED. This stands for minimal erythemic dose. Doesn't make any more sense?! What this means in reality is the dose of "sunlight" (actually UV B lamps) that is just at or below your burn time. This "sunlight" is shone on a test subject who is only clothed in swim wear. It produces the maximum vitamin D levels in the blood. The vitamin D levels are measured in the blood 24 hours after exposure and this is used to calculate how much vitamin D the body created.

The interesting thing that a unit of MED is the same across all the five different melanin (skin pigment) types. Say for someone like me that has a whiter than a ghost skin a MED in summer is 10 - 15 minutes. Where as someone with Asian or Indian genetics it would be about 30 minutes where as a dark skinned person of African genetics a MED could be up to 120 minutes.

Therefore the amount of sunlight you need to generate a MED is very dependent on skin pigmentation.

The next question is how much vitamin D does a MED produce? The answer is 10 - 20 000 IU's of vitamin D. Now go to your multi supplement and see how much it contains. The answer is likely to be about 400 IU or less. Even at 500 IU this is only 2.5 - 5.0 % of how much your body can produce in a day! I am very disturbed that the supplement levels are so low.... yet we think they are high as the RDI is only 200IU. This is silly, people get upset about mega doses of vitamins yet the body can make a hundred times the RDI of vitamin D.    

Reference: Symposium: Vitamin D Insufficiency: A Significant Risk Factor in Chronic Diseases and Potential Disease-Specific Biomarkers of Vitamin D Sufficiency. Circulating 25-Hydroxyvitamin D Levels Indicative of Vitamin D Sufficiency: Implications for Establishing a New Effective Dietary Intake Recommendation for Vitamin D1. Bruce W. Hollis. 2005 American Society for Nutritional Sciences.

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