Remember vitamin D, the “sunshine vitamin?” Well, we aren’t getting enough of it. Vitamin D used to be easy to get. Unfortunately, outside play, outdoor jobs, and weekends in the park are less common these days. Most of our lives are spent indoors without the sun exposure that our skin needs to create vitamin D. Furthermore, sunscreen and glass block the important wavelengths of light that are used to create this crucial vitamin.
It used to be that we thought vitamin D just helped strengthen bones by improving the body’s ability to absorb and use calcium, but recent research has shown that vitamin D also affects the immune system, muscles, blood pressure and the heart. Vitamin D deficiency has also been linked to the development of cancer, diabetes, fibromyalgia, high cholesterol and multiple sclerosis. As our knowledge of vitamin D grows, so does our understanding of its importance in our bodies.
Research from Jane Lukacs, Ph.D., of the University of Michigan, has found vitamin D deficiency to be increasingly prevalent, especially in African-American, Hispanic, Asian and dark-skinned individuals. Like sunscreen, darker skin, which has higher amounts of pigment (melanin), blocks the important light wavelengths from getting to the skin to make vitamin D.
Dr. Lukacs’ research also found that obesity is just one risk factor for vitamin D deficiency. Being overweight seems to lead to deficiency because vitamin D is “fat soluble” and gets stuck in the fat and cannot go where it needs to go. The most interesting part of the research is that the study was done in summer when sunlight is most abundant—a time when we don’t often worry about getting enough vitamin D.
Dr. W. Michael Hooten of the Mayo clinic also reported that in patients with chronic pain, individuals with vitamin D deficiency required significantly higher doses of narcotic pain medicine and required them longer than people who were not deficient in vitamin D. This research suggests that vitamin D has an effect on the relationship between nerves, muscles and pain.
A third study by Drs. Philippe Autier and Sara Gandini from the International Agency for Research on Cancer and the European Institute of Oncology, respectively, found that people who took a vitamin D supplement actually live longer. The average daily dose of vitamin D was 528 IU in the study, and people who took a vitamin D supplement lowered their risk of death, by any cause, by 7%. The rate was 8% lower if the supplement had been taken for at least three years. Unfortunately, the reason for this benefit is unclear at this time, but further research is ongoing. Regardless, this information is impressive and reminds us of how important vitamin D is for our overall health.
Recommendations for Vitamin D
- Keep wearing your sunscreen: It protects from skin cancer and skin aging.
- Be sure your daily supplement includes vitamin D.
- Make sure that your vitamin D supplement uses vitamin D3 (cholecalciferol).
- Try to get at least 400 to 800 IU each day. People over 50 should try to get at least 1000 IU each day.
- Most dairy products are enriched with vitamin D, so choose low-fat dairy products as part of your diet in addition to your daily supplement.
- It is possible to get too much vitamin D. Typically, this happens in people who take large amounts of cod liver oil. Try not to get more than 2000 IU of vitamin D each day from supplements and dietary sources.
- Ask your doctor to order a 25-hydroxyvitamin D blood test to be sure you are on track. If the result is below 20 ng/ml, you are deficient. An optimal level has not been established, but 30 to 40 ng/ml is a practical target.