Not getting enough of the "sunshine vitamin," Vitamin D, may pave the way for weak bones, high blood pressure and various kinds of cancer. Yet many middle-aged women are running low on it. Sunscreens with SPF 8 reduce your ability to synthesize Vitamin D by as much as 97.5 percent. (With the alarming rise in skin cancer, these precautions are necessary - so don't jettison your sunblock.)
In northern climes, the winter sun is often so weak that it can't provide even minimum levels of this important nutrient. And nutrition? It's hard to get enough extra Vitamin D in your daily diet — even if you eat large helpings of salmon and Vitamin D-enriched foods (some cereals, breads and milk).
Vitamin D is essential for healthy bones, helps to prevent hypertension and cancers of the breast, colon and ovaries. In fact, more than half of those diagnosed with fibromyalgia (muscle and bone aches) suffer from a Vitamin D deficiency.
If you think you have a problem, tell your doctor. You may need a blood test to determine your circulating blood concentration of 25- hydroxyvitamin D, or 25(OH)D, a component of Vitamin D. Researchers say the best way to treat an ongoing Vitamin D deficiency is to flood the system with 50,000 IU of it, once a week for eight weeks. The easiest solution for most women may be to take a multivitamin high in Vitamin D, or a supplement recommended by a health care practitioner.
The National Academy of Sciences recommends a maintenance dose of 200 IU of Vitamin D until age 50, and 400 IU for the years after that. Investigators at Boston University Medical Center, however, believe that we may require as much as 1,000 IU in the months we are exposed to weak sunlight.
Remember, too, that vitamin D is fat-soluble and too much will be as bad for you as too little. Fat soluble vitamins collect in your fat cells and can be toxic if taken in excess of the body's needs. It is important not to overdose on vitamins, despite what you may have heard from different health gurus.
General References
Alternative Therapies in Women's Health, Vol 5, No. 1 January 2003 p. 1-4 Garland CF, et al.
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Nesby-O'Dell S. et al. Hypovitaminosis D prevalence and determinants among African American and white women of reproductive age: Third National Health and Nutrition Examination Survey, 1989-1994. Am J Clin Nutr 2002: 76:187-192. Abstract
Tangpricha V, et al. Vitamin D insufficiency among free-living healthy young adults. Am J Med 2002:112:659-662. Abstract
Webb AR, et al. Influence of seasons and latitude on the cutaneous synthesis of vitamin D 3; Exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin. J Clin Endocrinol Metab 1988;67:373-378. Abstract
This article is for educational purposes only and is not intended as a substitute for medical advice. Please consult with a clinician to review any current symptoms and address your medical concerns.
