In Australia there’s an add on TV with the punchline “There’s nothing healthy about a tan.”
This add is complete a lie by the Australian Government, there’s plenty healthy about a tan.
I’m not sure how the government can run this add in a nation where 1/3 of adults are vitamin D deficient. Anyway, how much sun is good for us? How much is really unhealthy? Read on…
Vitamin D comes from the sun. But how much sun do you need?
According to this article, you need 10-15 minutes (full body) on a standard UV index of 7 day. If you start to go pink that’s too much. (That’s significantly less that the Australian Cancer council claims we need – see here. You’ll have to work out which one you trust. One has 30 footnotes, the other has 2.)
Full body = front and back on the body, arms & legs. Any longer and you start to burn. Once you’ve received your 10 minutes for the day, you need to wait 24 hours before you body replaces the oils on your skin to make more Vitamin D. So getting a lot of Sun on just your arms or face is bad. Getting a bit of sun all over your body is great!
Where I live in Dubbo that’s about 5 minutes sun-baking on each side (full body), in the middle of summer (UV index 14) or 30 min in the middle of the day each side in winter. (Max UV index 3).
UV index is here:
http://www.bom.gov.au/australia/uv/index.shtml
This is a very good article on Vitamin D:
http://www.overcomingmultiplesclerosis.org/Recovery-Program/Sunlight-and-Vitamin-D/
“This study showed that the correlation between low ultraviolet radiation and MS was considerably stronger than that between high UV and melanoma.”
Vitamin D and coeliac:
http://www.celiac.com/articles/21476/1/Vitamin-D-Preserves-the-Intestinal-Mucosal-Barrier/Page1.html