Vitamin D research has made the news recently. One study divided almost 8,400 adults into two groups: those who have metabolic syndrome (or Syndrome X) and those who don’t. Metabolic syndrome is defined as a combination of health conditions that place a person at high risk for heart disease. These conditions are type 2 diabetes, hypertension (high blood pressure), hyperlipidemia (high levels of fat in the blood), and obesity. Researchers measured blood levels of vitamin D and found an inverse correlation between vitamin D levels and incidence of metabolic syndrome. Those with metabolic syndrome had lower levels of vitamin D as compared to the healthy group, who had higher levels.
A second study reviewed 12 clinical trials that evaluated vitamin D supplementation and the risk of bone fractures. In the studies where patients took 700-800 IUs of vitamin D daily, the risk of fracture was reduced by about 25%. Vitamin D was ineffective at preventing fractures at doses of 400 IUs daily.
Lately, alternative physicians are trending toward recommending 1000 IUs or more of vitamin D, and physicians are finally looking at blood tests and finding that many of their patients are deficient in vitamin D. One reason may be that Americans are avoiding sun exposure, an important source of vitamin D, to minimize their risk of skin cancer. Vitamin D deficiency, however, is related to depression, osteoporosis, cancer, and seasonal affective disorder among others.