The temperature might not be the only thing plummeting this winter. Many people also will experience a decrease in their vitamin D levels, which can play a role in heart disease, according to a new review article in Circulation.
Vitamin D deficiency results in part from reduced exposure to sunlight, which is common during cold weather months when days are shorter and more time is spent indoors.
"Chronic vitamin D deficiency may be a culprit in heart disease, high blood pressure and metabolic syndrome," said Sue Penckofer, PhD, RN, study author and professor, Marcella Niehoff School of Nursing, Loyola University Chicago.
The review article cited a number of studies that linked vitamin D deficiency to heart disease. These studies found rates of severe disease or death may be 30 to 50 percent higher among sun-deprived individuals with heart disease.
Penckofer and colleagues concluded that diet alone is not sufficient to manage vitamin D levels. Treatment options to correct this level, such as vitamin D2 or D3, may decrease the risk of severe disease or death from cardiovascular disorders. The preferred range in the body is 30 - 60 ng/mL of 25(OH) vitamin D.
"Most physicians do not routinely test for vitamin D deficiency," said Penckofer. "However, most experts would agree that adults at risk for heart disease and others who experience fatigue joint pain or depression should have their vitamin D levels measured."
At Boston’s Mattapan Community Health Center, Dr. Douglass Bibuld’s prescriptions are as high as 7000 IU a day, when a patient is extremely deficient. Read about Mattapan at:
http://www.loe.org/shows/segments.htm?programID=08-P13-00044&segmentID=4
The FDA recently doubled the RDA, from 200 IU of D to 400. Unfortunately, announcement lulls Americans into thinking the problem is solved, but as many as 80% of us are deficient and need much more than 400 IU, especially people of color (melanin blocks the sun's ultraviolet B rays that make D in skin). We should listen to the 18 University of California experts who declared that the FDA’s recommended daily allowance be raised to 2000 IU. See:
http://newsroom.ucr.edu/cgi-bin/display.cgi?id=1968
Ideally, instead of following a one-size-fits-all RDA, we should all get a 25-OH-D blood test to find our current level and then supplement with D until we reach 50 ng/mL of D in our blood.
There are plenty of hints from the research that D deficiency impacts our nation's health and economy far beyond the illnesses already documented as due to deficiency. Since nearly every cell has D receptors, including brain cells, deficiency could be a factor in the Achievement Gap between white students and African American and Hispanic students, which has resisted all attempts to close. See:
http://goodschoolfood.org/vitamin_dropout.shtml