Why Too Much Vitamin-D Bad For Heart?

While small amounts of Vitamin-D can be found in foods including fatty fish (mackerel, sardines and tuna), 80 to 90 percent of what the body requires can get from exposure to sunlight. But during winter season or in cold northern climates where there is a lack of sunlight, people are often encouraged to take supplements.

This is because a deficiency in Vitamin-D would lead to many medical disorders including osteoporosis, heart disease, stroke and hypertension, diabetes and metabolic syndrome, and cancer.

However, people who take too much supplement in Vitamin-D might get into troubles too. Researchers from Intermountain Medical Center in Murray, Utah reported in November 2011 at the annual meeting of the American Heart Association that higher than normal levels of Vitamin-D could make the heart beat too fast and out of rhythm (atrial fibrillation).

By following 132,000 patients at a Utah based medical center, researchers found that the risk of newly developed atrial fibrillation jumped almost 3-fold when blood levels of Vitamin-D were high. The normal range for Vitamin-D is between 41 and 80 nanograms per deciliter (ng/dl). But the patients in the study had readings above 100 ng/dl.

People who are diagnosed with atrial fibrillation and are taking Vitamin-D supplements are advised to have their blood levels checked to ensure they are not taking excessive amount of Vitamin-D. According to researchers, the effects of high Vitamin-D on heart rhythms are reversible. The arrhythmias would also improve simply by cutting down the consumption.

As recommended by National Institute of Health, the daily intake of Vitamin-D for people age between 1 and 70 years old is 600 IUs (International Units), based on what is sufficient for bone health.

Vitamin-D can be obtained from several natural food sources include oily fish such as tuna or salmon. For instance, 3 ounces of cooked salmon contains 447 IUs of Vitamin-D per serving. Small amounts of Vitamin-D can also be found in cheese and egg yolks. The Department of Agriculture provides a comprehensive list of foods containing Vitamin-D.

Instead of assuming supplements sold over the counter are safe, people should check their blood level to make sure they are in the safe range simply because people absorb supplement differently.