Vitamin D and Multiple Sclerosis
A new study has confirmed that a lack of vitamin D triggers a gene response that can lead to multiple sclerosis--a disease that affects 2.5 million people worldwide. Scientists have hypothesized for years that a lack of vitamin D might play a role in the development of MS. Since sunlight is the major source of vitamin D, previous research looked at the connection between climate and the development of MS. Studies found that the closer people live to the equator, the lower their chances of getting MS, while people who live in places that don't get much sunlight for long periods of time, such as in Northern Europe, have far higher MS rates. A 2006 study out of the Harvard School of Public Health confirmed the connection by discovering that subjects who developed MS had the lowest blood levels of vitamin D.
While these earlier studies acknowledged the vitamin D/MS connection, this new study is the first to establish a genetic link between the lack of vitamin D and the disease. When the researchers, from Oxford University in England and the University of British Columbia, isolated a gene that triples the risk of MS and then exposed that gene to vitamin D, they found that the vitamin caused proteins to bind to the gene and switch it on, which provided for normal functioning. They hypothesized that without sufficient stores of vitamin D, the gene doesn't work properly. Instead, it interprets proteins as invaders and causes the body to produce T-cells, which would normally attack pathogens--but in this case, because the T-cells have faulty programming, they attack the protective sheaf around nerve cells, causing MS.
As I've written before, a deficiency of vitamin D puts you at risk for more than MS. Studies have shown a connection between too little of the vitamin and an increased risk of prostrate and breast cancers, colon cancer, a weakened immune system, cardiovascular problems, diabetes, hypertension, schizophrenia, depression, and kidney disease. In fact, research holds that getting enough vitamin D reduces the likelihood of getting serious diseases like cancer and diabetes by as much as 80 percent.
The seemingly obvious conclusion is that you should consume more vitamin D, but it isn't so simple. First, very few dietary sources contribute vitamin D, and those that do don't begin to provide enough even to meet the minimum daily requirement. You'd have to drink at least 10 large glasses of milk a day just to get anywhere near the minimum required, and then you accrue all the problems associated with dairy. Perhaps that's why more than half of all adults and most elderly people have a vitamin D deficiency. Also, the researchers believe that even a prenatal lack of vitamin D can lead to MS later in life--so if your Mom didn't have enough vitamin D, you might be suffering for it now (yet another reason to blame Mom for your woes). In fact, the authors say in a paper published in PLoS Genetics that a deficiency a generation back could carry over and cause MS down the line. That's downright Biblical (Exodus 34:7).
The best natural source of vitamin D really is sunshine. Just 15 minutes of exposure a day can provide the equivalent of 10,000 units taken orally. Traditional guidelines, which are absurdly low, set the minimum daily requirement at 200 IU (and most of us are deficient at that) or 400-600 IU for adults over the age of 50. Current research, on the other hand, says that to achieve optimal health you need between 1,000--4,000 IU per day - although that does not seem to have filtered down to the mainstream medical community yet.
Clearly, getting out in the sun is the most powerful and efficient way to get your daily dose, but if you live in Yakutat, Alaska or if it's winter wherever you are or if you have a rainy spell or you work all day in an office, you need to supplement. In fact, you probably need to supplement anyway. For one thing, suntan lotion cuts vitamin D absorption by up to 95 percent. If you're always wearing suntan lotion, you're not getting enough vitamin D. Also, long sleeves and burkas and any clothing that covers a large area of your skin reduces your vitamin D production. And if you have dark skin, you need to up the amount of sun exposure: African Americans, for instance, need five to ten times the amount of sun exposure that Caucasians do in order to produce enough D.
In fact, the Journal of the American Medical Association recently advised all adults to take supplements, reversing a long-standing policy of advising people to get their nutrients from food and to forget about vitamins. JAMA now concedes that 80 percent of Americans don't eat enough fruits and vegetables to meet the minimum daily requirement, that many of the requirements are set far too low, and that food sources just can't supply certain vitamins (like vitamin D) anyway.
While you can't get too much vitamin D from sunshine (the body regulates itself), it is possible to develop toxicity from taking too much in supplement form. The upper limit for vitamin D supplements, according to traditional thinking, is considered to be 2,000 units daily. It should be noted, however, that all recorded cases of vitamin D toxicity start in the range of 40,000 IU a day. In fact, current research indicates that any level below 10,000 IU a day is likely to be safe.
Bottom line: get out in the sun for 10 to 15 minutes daily, without sunscreen, weather permitting. If not the sun, then supplement between 1000-2000 IU a day. If you're pregnant, you need to be especially vigilant in this regard. And if you have kids, make sure that they get enough of the vitamin. As I recently wrote, a study last year showed that up to 40 percent of children between the ages of eight-months to two years are vitamin D deficient.