Several months ago, my wife Eve had a blood test and was subsequently informed by her physician that she was “very” deficient in vitamin D (also known as the “sunshine vitamin” because our bodies naturally generate it when exposed to solar UVB rays.) Since we live in Seattle, where it’s perpetually cloudy for approximately three-fourths of the year, Eve’s deficiency wasn’t too surprising. She started taking vitamin D supplements, and I started doing some research on vitamin D in general. I discovered three important things:
- A very large percentage of 1st world residents are vitamin D deficient because we spend so much time indoors (and often use sunscreen when outdoors), and,
- Vitamin D deficiency is linked to a disturbingly wide range of very serious diseases, including cancer, heart disease, autism, osteoporosis and multiple sclerosis, and,
- Because the “daily recommended minimum” intake of vitamin D is 400 IU (the amount found in many multi-vitamins), many people mistakenly believe that a multi-vitamin is a sufficient source of vitamin D even if, like me, you go weeks at a time without significant sun exposure. Even people who get sun exposure before or after work may not be entirely OK; most UVB radiation penetrates the Earth’s atmosphere from approximately 10am to 3pm. The National Institute of Health recommends 5 to 30 minutes of sun exposure between those times at least twice a week, sans sunscreen, to people who wish to self-synthesize the recommended minimum amount of vitamin D.