I get a lot of strange looks this time of year. I am sure that people are gossiping about a lifestyle choice I have made for myself and my son, in part because of what we have been learning about controlling autoimmune diseases.

We have tans. Real ones. From being in the sun without constantly reapplying sunscreen.

Now, we live outside Chicago…the cloudiest city besides Seattle. And we are never, ever, even a little bit, burnt. And we aren’t all tanned up by June 5th. I have lots of photos of our pasty early season skin, but by now we have managed to get a nice slow even tan. Our faces are a bit pale still but our bodies are very bronze.

Why would I do this?

The link between diet and autoimmune disease is becoming increasingly clear. And one of the clearest recommendations is that adequate intake of Vitamin D is critical to preventing and mitigating autoimmune diseases. Although celiac disease is deadly if not treated, it is among the better autoimmune diseases to have. It is not crippling like RA, colitis, or Crohn’s. There is no need to monitor anything overnight as there is with type 1 diabetes. There are no tricky drugs.

Vitamin D can be taken orally. Given our latitude here in Chicago, I spend the winters happily blocking the virtually non-existent sunshine (this far north the body cannot make vitamin D from sunshine half of the year) and swallowing supplements. However each gluten accident means that for some period of time (minimally about a month) we don’t digest food properly. So we might think we are taking a supplement but not absorb it at all. We have one big chance to bypass our digestive system and get our Vitamin D levels up over the 70 nanomoles per milliliter that we need.

We need to spend time in the sun letting the UVA rays actually tan us.

So yes, we have our SPF 15 zinc oxide block. Yes it is water-resistant. Yes we use it. But we spend a lot of time outdoors and it does wear off and slowly, slowly, we tan.

And since you should never, ever take the advice of a random blogger on science without evidence, here it is.

The gold standard of scientific evidence is multiple quality studies combined in a meta-analysis. This is the result of a meta-analysis of over 200 studies on the role of maintaining adequate Vitamin D levels in preventing and mitigating autoimmune disease.

This is another paper which has some charts outlining the role of Vitamin D in various specific autoimmune diseases

There are lots of others, surf PubMed for a while and check them out.

For what it is worth, my son and I are olive-skinned. We tan easily. If you are fair, then you need very little time in the high noon sun to get what you need to make vitamin D. If you are darker skinned you need more time in the sun to get what you need. It is literally 15 to 20 minutes at noon over most of your body (arms, legs, torso) most days (for the fair to olive skinned). You can then go back inside and put on SPF 90. Depending on the latitude, early and late sun will not help you produce vitamin D, so there is no need to risk a burn. Just sit outside in a tank top and shorts for 20 minutes and you are good.

Some people really cannot tolerate the sun. They should take the supplements and get their blood levels tested.

But for anyone with an autoimmune disorder, it is a good idea to get those D levels up.