Now that the dangerous rays of mid summer sun are retreating here in Australia, it might be time to top up on some high quality vitamin D. Yup, time to get into the sun! (And in northern hemisphere too: you’re sitting perfectly just before the sunshine storm)
Every cell in your body has a receptor for D, which makes it more like a hormone than a vitamin. It supports your immune health, is necessary for your body to absorb calcium, and let’s not forget about mood … many of us feel more blue in the winter when there’s less sunshine – or even after a day or two inside all this rain here at the moment!
Vitamin D is made by sunshine and our skin pigmentation is adapted to sun exposure. People living in the higher latitudes have developed light skin to help them take advantage of every possibility to produce vitamin D from sunshine. Unfortunately, for the most part, we do not live in our indigenous homelands and don’t live traditional lifestyles. This causes big problems with vitamin D status!
The ability to produce vitamin D from sun exposure varies with geographical location, skin pigmentation, percentage of body fat, and age.
In Australia there is an epidemic of skin cancer. In the last twenty years the already high rates of cancer have doubled in spite of a huge campaign to use sunscreens. In retrospect, the use of sunscreen decreases the skins ability to produce vitamin D by 97% to 100% by blocking the UVB radiation which produces vitamin D. By preventing burning of the skin, sunscreens may prevent certain types of skin cancer but because they are less protective of UVA than UVB radiation and promote longer exposure by preventing sunburn, they may actually increase the risk of others (arguably the worst, like BCC and CCC).
In general, contemporary attitudes towards sun exposure and sunscreens have not served us well. We should get some exposure to the sun every day that it is possible, we should not use sunscreen, but we should never expose our skin to the point of burning. The pain and inflammation of sun burn is our bodies’ way of saying “get out of the sun” and we should respect that. Having said that, it is important to be intelligent about sunscreen. If we are going to be overexposed for our pigment type, in actuality, it is certainly better to use sunscreen than to burn.
If vitamin D not produced in the skin as a result of appropriate exposure to UVB radiation then it must be ingested either from food or supplements. Although, obviously we would prefer to get our vitamin D from whole foods, this to can be problematic.
The primary dietary source of vitamin D is oily fish. A 3 1⁄2 ounce piece of salmon contains approximately 360 IU of vitamin D followed closely by mackerel with 340, Sardines with 250 and Tuna with 200. The problem with fish as a primary source of vitamin D is that fish often contain mercury and consuming enough fish to supply the optimal amounts could pose a very real risk. Farm raised fish should be avoided. An egg, according to the U.S.D.A., contains about 20 IU’s of vitamin D. It can be assumed that a free-range and grass fed egg would have significantly more. Liver contains 15 IU’s of vitamin D, but again, it would be very important to obtain liver from an organic and grass fed source in order to get the maximum benefit and avoid toxicity.
Industrialized milk, commercial baby formulas, and many processed cereals are fortified with vitamin D2. In the typical highly processed American diet this has been very important in the prevention of Rickets. Whole grains and milk even from organic or grass fed sources does not contain vitamin D in any significant amounts. Since many of us are interested in natural health often avoid fortified, processed foods, it is important to recognize that they must get their vitamin D from other sources.
Because of the logistics of getting enough sun exposure and the general lack of vitamin D in most diets, supplementation should be considered for most individuals, particularly in the Northern latitudes. The form of vitamin D produced in the skin and found in whole foods is vitamin D3 (cholecalciferal). Fortified foods and some supplements contain vitamin D2 (ergocalciferol). Vitamin D2 is manufactured by irradiating fungi and although useful, is less efficiently converted into the biologically active form of vitamin D (calcitriol). Cod liver oil is a rich source of vitamin D3, containing 1,360 IU’s per tablespoon. For many individuals this could be a useful supplemental source if they do not object to the taste and have the ability to properly digest fats. It is important to use only sources that have been tested for contamination, particularly mercury. Most of the professional grade supplement manufactures have a vitamin D3 supplement. To ensure efficient uptake, emulsified products should be considered.
Just make sure you get your D. Soak it, eat it, or supplement it. It supports your health more than we’ve ever realized.