Now that winter is here if you live in a cold climate like I do.

sun when i have the opportunity, and shiitakes.

sunshine. like a cat, i find the patches in my house and bask in them. when i walk i don't cover up. i also have used non-vegan sources in the past, so i won't discuss that here.

you only need a little bit of sunlight. a 15 minute walk a day will do it. and they are looking at getting more mushrooms exposed to sunlight so that they will have more vitamin D. but i think most mushrooms have trace amounts.

I'm a vegetarian, not a vegan, so I don't have to worry about that. The only source of Vit D for a vegan I know of is the sun.

Ergocalcifero is a vegan source that I believe occurs naturally in fungi and in fish oils. Just buy the Ergocalcifero vegan source supplement. Unless you are die-hard-core raw vegan, buy a ticket to a sunny location every winter.

I remember seeing a National Geographic pic of Russian or Alaskan schoolchildren gathered around a special light with just their underwear and goggles on during winter to get UVB rays. I wonder if that would work (cheaper than a ticket too) apparantly it only takes a few minutes to get enough exposure.

[en.wikipedia.org]

Vitamin D3 is produced in the skin by conversion of 7-dehydrocholesterol by UVB. Human skin exposed to sunlight can, under the right conditions, produce quantities as large as 20,000 IU in just a few minutes without any apparent toxicity. This is easily enough to avoid deficiency and builds up the body's stores.

Exposure to sunlight also destroys vitamin D, so long term exposure to sunlight cannot cause toxicity, as levels are self-adjusting.

However merely being exposed to sunlight does not automatically mean that vitamin D is produced, only the UVB in sunlight triggers vitamin D production, but UVB mainly reaches ground level when the sun is high in the sky. This occurs a few hours around solar midday (1 p.m. summertime). At higher latitudes, the sun is only high enough in the sky in summer. For example, in the United States, those living north of a line from San Francisco to Philadelphia (about 40 degrees of latitude) will not be able to produce it in significant quantities for 3 to 6 months a year.

Therefore from the end of summertime to the following spring humans run on stores which gradually deplete. By some estimates 10–20% of the population become at least mildly deficient by the end of winter, and deficiency is high even in very sunny countries like India. People who never go out in the midday sun become deficient even on supplementation at 100% of the RDA.

In addition, suntan lotion blocks production. Deficiencies are now much more common in Australia, which had a very successful "slip slop slap" campaign, though most of the deficient people have dark skin, cover up when outdoors or are confined indoors (for example: elderly people or those with a disability or serious illness).



Edited 1 time(s). Last edit at 10/16/2006 02:34AM by tropical.