It was originally thought to play a role only in the mineralization of bones and teeth by maintaining the correct phosphorous / calcium ratio.
Over time, research has linked low vitamin D levels with obesity, diabetes, cardiovascular disease, autoimmune disease, osteoporosis and cancer.
According to the CDC, in 2006 a whopping one fourth of the population was deficient in vitamin D. Eight percent were "at risk" for vitamin D deficiency illnesses and one percent had levels that were considered imminently harmful. According to Natural News, vitamin D is "perhaps the single most underrated nutrient in the world of nutrition."
What’s causing this epidemic of low vitamin D levels? One theory is that we are not outside as much as prior generations, and when we are, we slather on the sunscreen which prohibits UVB (the rays responsible for suntans) from penetrating the skin. These same UVB rays naturally produce vitamin D.
The time of day, the season, the altitude, the latitude and other factors come into play to determine how much UVB rays reach the skin. Vitamin D levels can become depleted without enough sunshine, and this is especially true during the winter months when we stay inside more and the sun is not as intense.
It is never a bad time to have your vitamin D level checked by a simple blood test. A normal 25-hydroxyvitamin D blood test will register above 30 nanograms per milliliter (ng/mL). Previously it was thought that levels 21 and below needed treatment, though more recently anything below 35 is addressed by many forward thinking practitioners. Using these levels, it is estimated that one billion people are deficient in vitamin D.
Recent studies reported in the New England Journal of Medicine and by the Vitamin D Council, indicate a link to depression.
SAD, Seasonal Affective Disorder, research is interesting as well. The National Institute of Health cites several studies where sunlight markedly improves mood. Of course even though we know sunlight increases vitamin D levels, this doesn’t prove that the increase in vitamin D is what is responsible. It also doesn’t prove that sunlight will work in those that are depressed and do not have SAD.
Here are a few important things to note regarding getting enough sunlight / vitamin D:
Now for the bad news. There has to be some bad news, right? Well, here it is. Sunscreens -- from the strongest to the weakest -- prohibit the body from making vitamin D by 95 percent. In light of this, there is a theory that more individuals are depressed these days because EVERYONE uses sunscreen and they're not taking vitamin D supplements.
This, of course, is something you'll never hear from the sunscreen industry because that would affect their bottom line. Your body needs the sunlight WITHOUT sunscreens to produce vitamin D. Even SPF 8 creams can prevent the production of the vitamin.
Vitamin D supplements can be found over the counter in just about any corner store. However, the high dose form, which contains 50,000 units of the vitamin and is taken once or twice a week, can only be obtained by prescription.
Many new studies on vitamin D and its role in the body. But in the meantime, the potential benefits of vitamin D for depression, should not be ignored.