Just last week we held a Health Care Class in the office on Vitamin D, since so many patients have been asking me about it and more and more people are aware that it is important, but lack some basic info like why it's important, should it be supplemented and if so, how much? A couple of years ago I started to look into the Vitamin D story in earnest and came across a lot of good stuff; so much good stuff in fact, that last week we held a Health Care Class in the office on the subject. I thought I'd pass on some of the highlights here.
Vitmain D has been linked to the activity of over 2,000 genes in the human genome, and we only have about 30,000. The old "dogma", DNA-RNA-Protein, (I know, what is dogma doing in science? Great question, look up Bruce Lipton, he is probably the best source on this right now). Anyway, according to "the Primacy of DNA", it's believed that we are our genes and that we have little to do with our genetic make up or with the expression of our genes. This has been the message for the last 60 years or so but as it turns out, our environments have much more influence over the expression of our genes than previously thought. It's been said that our genes load the gun, but our environment pulls the trigger. Well, Vitamin D, among other things, is one of those triggers that can unlock the potential of our DNA. And adequate Vitamin D levels are part of the healthy environment that a cell should find itself in. But it works the other way too; for example, toxins or even an accumulation of metabolic waste in and around the cell will affect DNA expression adversely, resulting in a variety of disease processes.
It's well known that Vitamin D can prevent ricketts or osteomalacia and is important in bone health. And now there is tremendous evidence that Vitamin D is important in proper immune function as well, from preventing the flu to overcoming cancer and autoimmune diseases like Multiple Sclerosis. When looking at the cost/risk associated with Vitamin D supplementation, it becomes increasingly difficult to argue why NOT to make it part of one's regular supplementation program, and it is one of the few supplements that I would recommend by itself.
Most people know that Vitamin D is made from the conversion of cholesterol in the surface layers of the skin by ultraviolet B radiation (UVB) from the sun. UVB is higher frequency radiation that penetrates more superficially, and is responsible for the conversion of cholesterol to Vitamin D. UVA, on the other hand, is of longer frequencies and penetrates deeper into the dermis, where the skin cells are alive and where cell replication takes place. Because the cells are alive and potentially replicating, it is the UVA radiation that potentially does the most damage and why UVA is associated with an increased risk in melanoma. Both UVA and UVB will tan the skin, although UVA does so a couple of days faster than UVB and this may be why tanning beds are typically heavy on the UVA exposure when the goal is a tan. Interestingly, there are usually several beds in a tanning salon that are higher on the UVB spectrum that are used for skin conditions and even to treat tuberulosis. More on that later. I caution people against thinking in terms of "good" and "bad" UV light, because even UVA has it's purpose. As it turns out, when left out in the sun for 15-20 minutes, the body will naturally stop producing Vitamim D, and it is the UVA rays that provide the negative feedback to the system so that the body does not overdose itself. Once again, nature really does know better. The critical point, for optimal vitamin D production naturally from the sun is to NOT BURN. EVER. The ideal is to get just the slightest pinking of the skin, termed "one minimal erythemal dose", which may only require a few minutes the first few times your skin sees the sun after a long winter or not seeing the sun for months. From there you can gradually build up your exposure safely, without increaseing your risk of melanoma, by not burning and developing a healthy tan.
The damage that occurs due to UVA exposure is of the mostly of free-radical type, so it should be clear that the best way to protect one's self from the potentially harmful effects is to saturate the skin (and body) with anti-oxidants. This is not, I repeat NOT done on the surface of the skin with miracle creams and sun tan lotion. This is done through diet. Make no mistake: your diet, whether it leans towards an inflammatory state or is anti-inflammatory, will have more of an impact on the aging of your skin (and the rest of your body for that matter) than anything you can do to it topically. I encourage everyone I come in contact with to familiarize themselves with anti-inflammatory diet changes and to make those changes to their diet as soon as possible, and for the rest of their life.
Since there is little question that Vitamin D levels should be optimized to drastically limit one's risk of cancer, infection, and autoimmune diseases, the question becomes how to get enough, and not too much, since overdosing is as harmful as deficiency. Ideally one should get it naturally through appropriate sun exposure, but because of the distance we are from the equator here in southwestern Pennsylvania, even if we were to sunbath on a sunny day anytime between mid-October and late March, the angle of the sun on the horizon does not allow penetration of the UVB rays through the earth's atmostphere. The sun must be at least 40 degrees on the horizon for that, and it doesn't happen here in the winter. (Note: glass windows block UVB rays, and not UVA) So if your shadow is taller than you are, even if it is 1:00 PM, you are not going to convert cholesterol to Vitamin D in your skin. So supplementation becomes important, but the dosage varies because everyone responds differently. For example, people with more adipose tissue (fat) will require a higher dose, since Vitamin D is fat-soluble. There is an ideal range that one should shoot for to optimize health, but the only way to get there is to do baseline blood work, supplement for a couple of months, and then retest. And it is important to push for the most useful test (25,Hydroxyvitamin D), which according to Dr. Joe Mercola (www.mercola.com) is offered by LabCorp and not Quest Diagnostics. Luckily this is not expensive, especially compared to the alternative (flu, cancer, etc.). As luck would have it, we do our lab work through LabCorp. And it is important to use D3 (cholecalciferol) and not D2 (ergocalciferol)which is very difficult for the body to use. Unfortunately, the food industry relies heavily on fortification of food with D2, because it is cheaper.
I've had people say that they live in Florida and are in the sun all year long but still got a cold. My response is that as much as we try to simply health, it is multi-factorial, and many things come into play, Vitmain D being just one of them, although apparently a huge one. I also offer this to consider: Lifegaurds typically have much high D levels than surfers, even though both are out in the sun a ton. As it turns out, D is made in the superficial layers of the skin, and it takes up to 48 hours to absorb it into the blood stream after it is synthesized. So surfers, and those who shower with soap, are washing off the majority of the newly made Vitamin D. I'm not saying to not bathe, I'm just saying this is a factor and save social considerations, we bathe too much and with chemicals that are too harsh on our body's systems. With that, you could just stick to washing the groin and axilla (underarm) for the most part. Don't shoot the messenger here.
As far as Vitamin D and bone health, let me make a couple of points. Vitamin D allows the absorption of calcium and other minerals in the gastro-intestinal tract. The minerals are absorbed into the blood, and it is poly-unsaturated fats (sesame, corn, flax, etc.) that tranfer Calcium into the tissue and bone. Many people are aware that Calcium is important, but beware of the ubiquitous Calcium Carbonate (limestone) that is so common in supplements and that the body does not utilize well. Once again, it is unfortunate that the food industry fortifies its food "products" with calcium carbonate. Calcium from plants and vegetables comes in other forms like calcium citrate, which is very readily absorbed and utilized by the body. Further, acid levels in the stomach must be sufficiently high enough for mineral absorption as well, which makes the idea of Tums with calcium "something your body needs anyway" misleading at best, because it is virtually impossible to absorb minerals without enough acid. Believe it or not, there is a very quick way to check tissue calcium in the office with a blood pressure cuff. It only takes a minute. We do this routinely in the office and it's a good way to for people to see if they are absorbing and utilizing the Caclium that they are taking. Because if they aren't absorbing it into the tissue, it is either getting flushed down the drain or accumulating in the blood putting them at risk for other problems.
If someone were to come into the office with a concern for bone health or to boost immune function with Vitamin D, the first thing I would tell them is that the body does not use nutrients in isolation, and that Vitamin D is only one part, (and we now know how important) of a balanced supplement program. Currently I put Vitamin D as third on my list of most important "bang for your buck" supplements. The first two are 1)good pure fish oil that has documented proof it is free of heavy metals and other harmful chemicals like PCBs and 2)a whole food liquid multi-vitamin multi-mineral that is easily absorbed and utilized. These are what I use in the office and with family and friends with outstanding results.
I hope this was helpful and if you have any more questions you can reach me at the office!