Vitamin D may well be implicated in your depression, particularly in the dark months of winter. We actually get the lion’s share of our vitamin D through sun exposure. As sun our skin, our body literally transforms it into vitamin D. Our body is very good at producing extra vitamin D in the summer months and storing it to help us through the darker months of winter when our skin tends to be guarded under coats, scarves, and hats. If we have not stored enough for those long winter months, we are far more likely to suffer from depression in the winter. As we age, our skin is less efficient in making vitamin D. Older people are more likely to be deficient and it turns out that older people with depression are more likely to be deficient according to this 2008 study in the Archives of General Psychiatry, suggesting a link between vitamin D deficiency and depression.
However at any age, those of us who are desk jockeys and see nary a bit of sunlight at any time of the year may really need to look at a vitamin D supplement.
Vitamin D Need is Individual-Specific
How much vitamin D you need actually depends on you — your skin type, your body mass index, your age, and your latitude. If you have lighter skin, you will make more vitamin D in the sunlight. If you are obese, you actually need more. If you are older, your skin will not produce as much. If you do not eat foods high in it or fortified with it, you need more. If you do not actually get out in the sun, you may not have levels that are adequate.
Here’s a quick video on the topic which you can also find here.
Your Vitamin D Levels
What everyone needs to do is get tested, particularly in the winter. ZRT Labs is the go-to lab for Vitamin D testing and is promoted through two sites:
The Grassroots Health site is using the questionnaires for a study, but it is extensive and may not be worth the small savings they offer except insofar as you are helping to further knowledge of vitamin D.
If You Are Vitamin D Deficient
If your results come back low, you will need to supplement your vitamin D until your levels increase. The Vitamin D Council has a good bit of information to help you start thinking about your levels. It recommends dosage amounts if you are deficient. You can find vitamin D3 supplements in health food stores or take a cod liver oil for its vitamin D content.
Summer Sun is Your Best Opportunity
By far the most effective way to improve your vitamin D levels is to get more sun on your skin. Before turning your skin to leather over this recommendation, read the suggestions at the Vitamin D Council on sunlight and indoor tanning. They make some important points:
- You will make most vitamin D in the mid-day of summer months. It turns out that the hours we are told to avoid the sun to avoid the sun’s radiation are the same hours we make the most vitamin D.
- Our torsos produce vitamin D the best. Our arms and legs do a decent job and our hands and face are the least effective.
- You are likely to make more vitamin D at higher altitudes. Beach bums at sea level likely make up for the difference by spending a lot more time in the sun.
- Sunscreen and windows block UVB rays and, as a result, block the production of vitamin D.
- If you are extremely fair, you will produce vitamin D with less sun exposure.
In my own routines, I cover up while gardening and I do lay out all year long as weather permits. When I lay out, I expose my legs and torso but keep my face, hands, and upper chest and neck covered. I have the most skin damage in those areas and do not want to increase their exposure. It is a relaxing ritual that I try to do for thirty minutes as often as I can manage.
Vitamin D In Food?
If sun exposure does not fit with your lifestyle, do not rely on your diet to keep up your vitamin D levels. The best sources of vitamin D in food are certain fish, but they contain very little when you consider your vitamin D needs. I discuss food sources of vitamin D in the video below. I discuss lard specifically because I have gotten many questions over the years about lard as a vitamin D super food.
Your best bet to supplement your vitamin D is cod liver oil, a great option for the wintertime or even during the summer if you get very little sun exposure.