With the emergence as fish oil as a mainstream supplement, many people are looking around and trying to figure out what the next big thing is going to be. Well, if you want a head-start on everyone else, a great place to look would be Vitamin D. Vitamin D (particularly “the deficiency of”) has been building a huge buzz with fitness and nutrition experts and will probably be the next big supplement.
The funny thing about “Vitamin” D is that it isn’t even technically a vitamin; it’s a fat-soluble prohormone, which means it’s a hormone that has no activity by itself. Vitamin D is notorious as the vitamin we get from the sun, which is also kind of a misnomer since the “vitamin” is a product of a chemical reaction caused by the sun. Humans produce Vitamin D3 (cholecalciferol) in the skin when UV rays from the sun irradiate 7-dehydrocholesterol, but all forms of Vitamin D (i.e. the two major forms D2 & D3) are inactive and must undergo a couple of chemical reactions in your liver and kidneys to be converted into the active form, Calcitriol.
The complicated science stuff aside, why is Vitamin D important and why is deficiency such a problem? This vitamin is essential for many processes in the body that deal with physical performance and mood and is particularly important in regards to bone density. Studies have linked Vitamin D deficiency as a major risk factor for 17 different types of cancers, type I and II Diabetes, Parkinson’s, Alzheimer’s and has been shown to possibly contribute to Seasonal Affective Disorder and the development of "Syndrome X"/prediabetes. Recent studies have shown that people with lowest levels of Vitamin D had as much as a 27% higher mortality rate from any cause of death. Deficiency can also cause many bone diseases such as rickets, osteomalacia and osteoporosis due to decreased bone mineralization and cartilage degradation. Vitamin D combats these bone diseases by increasing calcium flow and absorption in the intestines and kidneys, and by inhibiting calcitonin production in the thyroid gland.
Some of the most interesting findings with vitamin D pertain to athletic performance. The various forms of Vitamin D are secosteroids, meaning that their chemical structure is the same as other steroid hormones, but with a few broken chemical bonds. Studies in Germany in the 1920s, and again in Russia in the 1950s, showed significant improvement in performance by irradiated athletes. Improvements seen with Vitamin D supplementation include improved neuromuscular functioning, increased reaction time, improved muscle protein synthesis and anabolism, increased insulin sensitivity, lowered blood pressure and some evidence even exists in pointing to increased fat loss.
With all these potential improvements and health risks, it’s obvious to see why Vitamin D deficiency is a cause for concern not just for athletes, but also for the general population. Considering all the benefits, you would think that Vitamin D would be plentiful, but there are several roadblocks that can be easily overcome.
1. Bioavailability – there is a very short list of foods that naturally contain Vitamin D: fatty fish such as mackerel, halibut and cod, irradiated mushrooms, eggs and beef liver. Of these, only eggs are a regular staple in the American diet, and none of these foods contain large amounts of Vitamin D.
2. Location – UV exposure for adequate Vitamin D production does exist, but pretty much only in tropical climates. Few places in North America provide enough sunlight to cause Vitamin D synthesis in the skin.
3. Regulation – government regulation of supplements doesn’t exist since the FDA only deals with foods, but even the RDA from doctors, health organizations and government guidelines is insufficient and most multivitamins fall well short of the amounts shown to provide the benefits highlighted above.
These problems can be circumvented using a few methods. Liquid D3 gel-caps and fish liver oil supplements are easy enough to find in stores, most of them containing around 1000 IU’s of Vitamin D. On top of supplementing, it is fairly easy to make sure you get at least 10-15 minutes of uninterrupted sunlight in the middle of the day. You can use tanning beds if you live in an area with really poor sun exposure, but that carries with it the increased risk of skin cancer so that decision is at your discretion. Experts and knowledgeable professionals recommend getting between 1000-5000 IU’s of D3 every day, but shooting somewhere in the middle around 2000-3000 IU’s is probably your best bet and most feasible from a scheduling standpoint.
Vitamin D is the next big thing, so make sure you stay ahead of the curve and aren’t “Deficient in D.”