Vitamin D: The Kidney Vitamin?

August 12, 2014, 10:06am EDT

Many Americans are deficient in an important vitamin—vitamin D. The Centers for Disease Control and Prevention's latest information has found that more than one-half of Americans of all ages have low levels of vitamin D. More and more information is pointing to how important vitamin D is to the body, especially the strength of bones.

In addition to maintaining healthy bones, newer research shows that vitamin D may also protect against heart disease. In fact, people with the lowest vitamin D levels had a 40% higher risk of cardiovascular disease in one study.

Talk with your doctor or dietitian before taking any vitamins that are not ordered for you. There are different types of vitamin D. Your doctor will be very specific about the type and amount you should be taking.

Why is vitamin D connected to the kidney? The kidneys are an important part of helping the body use vitamin D. Vitamin D comes from two sources in people. It could either be exposure to the sun's ultraviolet B radiation. Or, it is absorbed from food or food supplements. The kidneys have an important role in making vitamin D useful to the body. The kidneys convert vitamin D from supplements or the sun to the active form of vitamin D that is needed by the body. With chronic kidney disease, low vitamin D levels can be found, sometimes even severely low levels. This may occur because injured kidneys are less able to convert vitamin D into its active form.

Vitamin D deficiencies have been reported in all types of people, but especially in the elderly, people with darker skin color (African-Americans), and people with a higher body mass index (obesity).

Your vitamin D levels can be tested with a blood test. Remember, there are different types of vitamin D so you shouldn't start taking a supplement on your own. Always check with your doctor before you take any supplements.