Lack Of Vitamin D Could Spell Heart Trouble:
"Vitamin D deficiency—which is traditionally associated with bone and muscle weakness—may also increase the risk of cardiovascular disease (CVD). A growing body of evidence links low 25-hydroxyvitamin D levels to common CVD risk factors such as hypertension, obesity and diabetes, as well as major cardiovascular events including stroke and congestive heart failure.
"Vitamin D deficiency is an unrecognized, emerging cardiovascular risk factor, which should be screened for and treated," said James H. O'Keefe, M.D., cardiologist and director of Preventive Cardiology at the Mid America Heart Institute, Kansas City, MO. "Vitamin D is easy to assess, and supplementation is simple, safe and inexpensive."
It is estimated that up to half of U.S. adults and 30 percent of children and teenagers have vitamin D deficiency, which is defined as a 25(OH)D level of <20ng/ml. Low vitamin D levels activate the renin-angiostensin-aldosterone system and, in doing so, predispose patients to hypertension and a stiffening and thickening of the heart and blood vessels. Vitamin D deficiency also alters hormone levels and immune function, which can increase the risk of diabetes, a major contributor to CVD.
Recent data from the Framingham Heart Study suggest patients with vitamin D levels below 15 ng/ml were twice as likely to experience a heart attack, stroke or other CV event within the next five years compared to those with higher levels. This risk remained even when researchers adjusted for traditional CV risk factors.
Treating Vitamin D Deficiency
In the absence of clinical guidelines, the authors outline specific recommendations for restoring and maintaining optimal vitamin D levels in CV patients. These patients should initially be treated with 50,000 IU of vitamin D2 or D3 once weekly for 8 to 12 weeks. Maintenance therapy should be continued using one of the following strategies:
* 50,000 IU vitamin D2 or D3every 2 weeks;
* 1,000 to 2,000 IU vitamin D3 daily;
* Sunlight exposure for 10 minutes for Caucasian patients (longer for people with increased skin pigmentation) between the hours of 10 a.m. to 3 p.m.
Vitamin D supplements appear to be safe. In rare cases, vitamin D toxicity (causing high calcium levels and kidney stones) is possible, but only when taking in excess of 20,000 units a day."