Vitamin D for Improved Artery Health
Researchers keep finding new reasons to make sure you’re getting adequate amounts of vitamin D. The latest focus? Your blood vessels. Growing evidence links vitamin D with improved vascular health, including recent research by Tufts’ Jennifer S. Buell that associated vitamin D levels with improved vascular health specifically in the brain.
Now an analysis of data from the National Health and Nutrition Examination Survey (NHANES) finds vitamin D may help prevent peripheral artery disease. Associated with decreased blood flow in the legs, peripheral artery disease (PAD) affects 8 million Americans and is linked with other serious health conditions.
Publishing their findings in Arteriosclerosis, Thrombosis, and Vascular Biology, lead researcher Michal L. Melamed, MD, MHS, of the Albert Einstein College of Medicine and colleagues analyzed data from 4,839 NHANES participants. The large, diverse study sample was described as nationally representative, with participants’ average age at just over 61 — since the risk of PAD is higher among older people.
Researchers divided the sample into four groups, according to subjects’ blood levels of vitamin D. The study found that increasing levels of the vitamin were associated with a lower prevalence of PAD. The occurrence of PAD dropped from 8.1% in the group with the lowest vitamin D levels to 5.4%, 4.9% and 3.7% as vitamin D levels rose in each quartile.
After adjusting for age, sex, race and co-existing health problems, the researchers calculated that PAD risk was 80% higher in the lowest-level group as compared with those with the highest levels of vitamin D. In fact, for each 10 nanogram/milliliter drop in blood levels of vitamin D, subjects’ risk of PAD rose by 35%.
Vitamin D is a fat-soluble nutrient that is naturally present in only a few foods. Fortified foods — like milk, orange juice and commercial breakfast cereals — provide most of the vitamin D in the American diet. Vitamin D refers to two precursors: D3 (cholecalciferol), which is produced in the skin upon exposure to sunlight, and D2 (ergocalciferol), which comes from dietary sources, especially oily fish, egg yolks and liver.
But not everyone agrees about the need to turn to supplements to increase the intake of vitamin D.
“We recommend eating a balanced diet,” said Dr. Melamed, suggesting that in addition to foods that naturally contain the nutrient, people eat more vitamin D-fortified foods. “We would not recommend that people start taking vitamin D supplements without talking to their doctors.”
The researchers also pointed out that their study does not prove a causal relationship between Vitamin D and reduced artery disease — that is, the study does not prove that vitamin D, in and of itself, lowers PAD risk. It’s possible, they wrote, that higher vitamin D levels may simply be evidence of a healthy diet and lifestyle practices.
TO LEARN MORE: Arteriosclerosis, Thrombosis, and Vascular Biology, online before print at <atvb.ahajournals.org/cgi/content/abstract/ATVBAHA.108.165886v1>.
