If you didn’t know any better, you might think vitamin D had just been discovered, with all the “news” about it! Well, Vitamin D has been around for awhile, it’s just celebrating a sort of “rebirth” in the mainstream media and medical profession. It is a vitamin AND a hormone, but it was rather ignored for years.
Researchers, scientists and doctors are now beginning to recognize vitamin D for the various functions it performs—and for its importance to overall health.
First, why did I call it a vitamin and a hormone? By definition, a hormone is produced in one place (a gland, like the thyroid or adrenal glands, or in the case of vitamin D, skin cells exposed to sunlight) and is transported by the blood to function in another part of the body.
A vitamin is defined as a substance that is necessary in small quantities for normal growth and activity. Both those definitions fit Vitamin D. Chemically, vitamin D also looks very much like steroid hormones. It is also fat-soluble, meaning it can be stored in fat—something that may be important during those sun-deficient winter months.
We don’t know all the functions that vitamin D has, but we do know that Vitamin D is critically important for strong teeth and bones, and in maintaining calcium and phosphate levels. We also know that vitamin D is required for proper cell growth, muscle function, inflammatory responses and immunity.
Extreme and severe vitamin D deficiency can result in the disorder known as rickets—a softening of the bones in children. These kids actually have bent bones because their bones literally bend under their own weight!
Less severe deficiencies in vitamin D are associated with colon and other cancers, autoimmune disease, infectious diseases, obesity, depression, and heart disease. It has also been linked to food sensitivities….hmmmm. Colon problems? Autoimmune disease? Food sensitivities? Gee…..could vitamin D be important in celiac and in gluten sensitivities? As a friend of mine used to say…..do ya think?!
It turns out vitamin D is important in celiac disease and gluten sensitivity…. more about that in a bit, first, let’s see where we get vitamin D from!
The main natural source of Vitamin D is though sun exposure. Deep down (well, not so deep…) I have a crazy notion that part of the reason that Vitamin D deficiencies have become so important and widespread is that for years we have been told to minimize skin exposure to sun because of the risks of skin cancer.
“Don’t forget your SPF 30 gazillion!!”
“Avoid the sun if you don’t want to get skin cancer!!”
Well, the fact is that we can usually get about 90% of our vitamin D from sun exposure. And, another important fact is that the rates of skin cancer have NOT gone down despite all the slathering of sunblock that has gone on!
Now, I am not saying you should spend hours and hours sun bathing with no protection, but I am saying that exposing your face, arms, back and/or legs 2 – 3 times a week to the early afternoon sun for 10-30 minutes will probably give you a sufficient amount of vitamin D and not increase your risk of skin cancer substantially.
There was a recent article in the American Journal of Clinical Nutrition that stated “The major cause of vitamin D deficiency is the lack of appreciation that sun exposure in moderation (emphasis added) is the major source of vitamin D for most humans.”
Now, moderation means a lot of different things to different people! Ask me what a moderate amount of chocolate ice cream is….and it very well may be more that a moderate amount for someone else!
A lot also depends on your skin tone—the darker your skin, the more exposure you need, but a “moderate” amount of sunlight is likely to be safe—after all, humans have been in the sun for thousands of years and most people feel better with the sun! There’s that whole problem with Seasonal Affective Disorder (SAD) that occurs when the amount of sun we receive decreases.
We don’t really know how much sun is too much—but recent studies at the Australian National University (and from what I hear, they get quite a bit of sun!) indicate that more lives are lost and more diseases are caused by a lack of sunlight than are caused by too much sunlight.
So, the idea of getting 10-30 minutes of sun 2-3 times a week seems reasonable.
The sunlight we get consists of three types of ultraviolet (UV) radiation—UVA, UVB and UVC. Only UVB can stimulate vitamin D synthesis by converting 7-dehydrocholesterol to previtamin D3. Previtamin D3 is further converted in the liver and kidneys to vitamin D3. Other than the sun, other sources of Vitamin D are fish, dairy foods, and eggs.
How much vitamin D should we take as a supplement if we live in an area without much sun?
Here’s the part where it gets a bit controversial—some reasons are technical, others because we simply don’t know enough. Conventional medicine has decided that in adults, vitamin D deficiency is defined as a serum vitamin D3 level of less than 20 ng/mL and insufficiency as a vitamin D level of 20-30 ng/mL.
But, during a recent (5/11) talk I attended, Dr Alan Gaby, author of Nutritional Medicine and with over 30 years experience in nutritional medicine put forth some important questions about these levels. I’ve borrowed his suggestions on the amount of sun to get. He also suggested taking vitamin D as a supplement at 800-1200 IU/day, primarily during the winter months.
So, what’s the connection with celiac disease and gluten sensitivity?
First, since vitamin D is a fat soluble vitamin, people with celiac and gluten sensitivity won’t absorb much vitamin D from whatever food sources they eat—and that can lead to osteomalacia or a softening of the bones that has been increasingly associated with CD.
If you get most of your vitamin D from sun, that won’t be a problem because it won’t have to be absorbed by the gut!
Second, CD and gluten sensitivity are auto-immune disorders—vitamin D also works with immune cells to shift the body towards an anti-inflammatory state—in other words, vitamin D can help reduce the inflammation in CD and gluten sensitivity.
Third, vitamin D helps maintain a proper balance of gut bacteria—thought to be absolutely critical to the development of food sensitivities of all kinds.
The common mainstream approach to suspected vitamin D deficiency is the use of the intramuscular shot of 50,000IU of ergocalciferol. Ergocalciferol is a synthetic, man-made derivative—a synthetic vitamin D2 and not the D3 you usually read about.
It does NOT work the same way that vitamin D3 does.
You may be better off trying to achieve the greater the presumed optimal 30ng/mL level of vitamin D more slowly—by getting some sun and supplementing (with advice from your physician) in the range of 800-1200 IU/day.