Vitamin D and High Blood Pressure

New research indicates that women who do not have enough vitamin D before menopause may have an increased risk of developing high blood pressure later on.

The study also found that if you have vitamin deficiency by age 45, the likelihood of developing hypertension in midlife increases threefold.

The researchers examined data from a Michigan Bone Health and Metabolism Study that monitored 559 women in their 20s, 30s and early 40s for 15 years. They looked at the women’s vitamin D levels at upon entering the study. They also took blood pressure readings each year.

By the end of the study, the average age of the women was 53, and about one in four had developed high blood pressure.

According to lead researcher Flojaune C. Griffin, MPH, vitamin D deficiency earlier in life seemed to be a predictor of hypertension a decade later.

"This is preliminary data so we can’t say with certainty that low vitamin D levels are directly linked to high blood pressure," says Griffin, "But this may be another example of how what you do early in life impacts your health years later."

Vitamin D

Earlier studies also suggest that vitamin D may help protect against heart disease. Another recent study named vitamin D deficiency as a possible risk factor for a number of other diseases, including arthritis, diabetes, multiple sclerosis, multiple cancers, and even tuberculosis. Apart from bone diseases such as osteoporosis and rickets which are clearly associated with vitamin D deficiency, none of these other links have been proven.

The most convenient way for us to get enough vitamin C is to be exposed to sunlight. Foods are also good sources of vitamin D, including milk, yogurt, and fortified juices and cereals, though experts say that it would be very difficult to get sufficient amounts of the vitamin from food sources alone.

A consensus regarding the optimal vitamin D supplement dosage is yet to be reached. Most multivitamins contain 400IU of vitamin D. However, Griffin says most of the newer studies suggest that the optimal vitamin D dosage may be closer to 10 times that amount.

"It may be time to consider the possibility that we need a more nuanced public health message about sun exposure so that we are not putting people at risk for skin cancer, but are also alerting them to the fact that a few minutes of exposure before they put on sunscreen may be a good thing," she says. Study co-author and University of Michigan professor of epidemiology Mary Fran Sowers, PhD, agree. "We have recognized for a long time that it takes very limited sun exposure to get adequate vitamin D," she adds.

More study

Some experts on the other hand, say that the link between vitamin D deficiency earlier in life and high blood pressure in middle age needs further study.

Hypertension expert Rhian M. Touyz, MD, PhD, of the University of Ottawa, says the idea is intriguing but unproven.

Cardiologist Nieca Goldberg, MD, director of the Women’s Heart Program at New York University, agrees. "This research certainly raises some interesting questions. "Vitamin D is important for the absorption of calcium and its role in bone health is proven. If we find out that it also helps prevent high blood pressure, that’s a real plus. But we aren’t there yet."

Source: WebMD