Vitamin D, also known as the ‘sunshine vitamin’, is a steroid hormone precursor.
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.
What does this have to do with mental health / psychiatry?
Recent studies reported in the New England Journal of Medicine and by the Vitamin D Council, indicate a link to depression.
Canadian researchers reviewed 14 studies, consisting of 31,424 participants and found a strong correlation between depression and a lack of Vitamin D. The lower the Vitamin D level, the greater the chance of depression. But, the big question is still causality. Does one get depressed because of a deficiency of Vitamin D, or does depression lower the vitamin level?
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:
- The healing properties of natural sunlight CANNOT penetrate glass. That's right. You cannot sit inside your home or car and reap the benefits of sitting in a sunny spot. You must go outside.
- If you have dark skin, you'll need about 25 times more exposure time as a light skinned individual to produce the same amount of vitamin D.
- Your body cannot absorb calcium without enough vitamin D. You can take all the calcium you want, but will receive no benefit unless vitamin D is present.
- A vitamin D deficiency is not reversed immediately. You're looking at months of sunlight and/or supplements before levels return to normal.
- Your kidneys and liver activate vitamin D. Having kidney disease or a damaged liver will hinder the ability to activate vitamin D when needed.
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.
