Low vitamin D linked to prehypertension

By David Liu, PHD.

Sunday Jan 1, 2012 (foodconsumer.org) -- Vitamin D deficiency is associated with high blood pressure or hypertension. But a new study in the the journal Kidney & Blood Pressure Research suggests that low serum vitamin d levels may be responsible for prehypertension too.

The study led by Charumathi Sabanayagama of West Virginia University School of Medicine, Morgantown, W. Va. and colleagues shows that those whose vitamin D levels were in the lowest quartile were 48 percent more likely to suffer prehypertension, compared with those whose vitamin D levels were in the highest quartile.

Prehypertension is a condition in which an individual has a systolic pressure at 120 to 139 mm Hg or a diastolic pressure at 80 to 89 mm Hg. In comparison, hypertension or commonly known as high blood pressure is defined as a condition in which blood pressure values go above 140/90 mm Hg.

The U.S government estimated about 30 percent of U.S. men and women have prehypertension.  It remains unknown what causes prehypertension, but it is generally believed that overweight, a family history of hypertension, a sedentary lifestyle, eating high sodium foods, smoking, and excessive alcohol intake may be risk factors for elevated blood pressure.

The current study followed 9215 participants older than 20 who were enrolled in the 3rd National Health and Nutrition Examination Survey and were free of hypertension at baseline.   Of the participants, 3712 were found to have prehypertension.

The researchers found "Lower serum vitamin D levels were found to be associated with prehypertension independent of potential confounders including body mass index (BMI), serum cholesterol, C-reactive protein and estimated glomerular filtration rate."

They said in their study report that "This association persisted in subgroup analyses by gender, race-ethnicity and BMI. Conclusion: Lower serum vitamin D levels are associated with prehypertension in a representative sample of US adults."

People with prehypertension are at risk of developing hypertension. 

Like hypertension, pre-hypertension can also boost the risk for heart attack, stroke, congestive heart failure, and renal failure or kidney failure.  Studies show that a prehypertensive person is three times more likely to suffer a heart attack and 1.7 times more likely to experience heart disease than those with normal blood pressure.

High blood pressure, which affects about 46 million people in the U.S., may result in complications including increased risk for hardening of the arteries, which predisposes individuals to heart disease, peripheral vascular disease, and strokes.

Natural vitamin D is very cheap.  Sun exposure at the hottest hours of the day for 15 minutes may get a person enough vitamin D.  This vitamin is also found in a few foods including fatty cold water fish such as salmon, eggs, and mushroom.  Vitamin D is also added in processed and packaged foods. 

People can take vitamin D supplements to acquire high doses of this sunshine vitamin, which are considered necessary for the nutrient to exert a protective effect against a range of diseases including high blood pressure, and heart disease.