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Are You Getting Enough Vitamin D?

As the days get shorter and winter approaches, most Americans will be soaking in fewer sun rays. But that's not necessarily a good thing, according to Consumer Reports on Health.

The body relies on the sun to get most of the vitamin D it needs to stay healthy. Ronni Sandroff, editor of Consumer Reports on Health, visited The Early Show to explain that its current issue reveals that many people suffer from Vitamin D deficiencies due to a lack of sun exposure, and that's a bigger problem than previously thought.

During the cold months of the year, Americans in the northern part of the country are most likely to have insufficient levels of vitamin D. They are getting less sunlight and what they are getting from the sun is not enough to help them. On average, people recieve 90 percent of the vitamin D they need from sunlight and 10 percent from their diet.

Sandroff says people should get enough vitamin D by exposing themselves to the sun for 10 to 15 minutes a day without sunscreen during the warmer seasons of the year — depending upon how dark your skin is, how intense the sun is and the season. The winter sun is too weak to help. A recent study estimates that tens of thousands of Americans die each year of cancers possibly caused by too little sun exposure and too little vitamin D. However, Consumer Reports on Health acknowledges that too much sunlight can cause skin cancer.

Vitamin D helps the body absorb calcium from food, which makes minerals available to the bones. Deficiency of vitamin D prevents new bone tissue from hardening, a condition known as rickets in children and osteomalacia in adults. It can also increase problems with osteoporosis in women. Moderate insufficient levels of vitamin D, can increase the risk of fractures.

Research studies have found that insufficient levels of vitamin D can also contribute to developing different types of cancer such as colon and prostate cancer, heart disease and diabetes.

Sandroff says the people at the greatest risk of having a vitamin D deficiency are people 65 or older, African-Americans and the obese.

Seniors tend to wear more protective clothing and stay indoors more than younger people, and their skin loses its ability to synthesize the vitamin. Also, older people are more likely to take laxatives and a cholesterol lowering drug called Questran, which interferes with the absorption of vitamin D. Questran is the only cholesterol-lowering drug that has been found to cause this problem.

African-Americans may suffer from vitamin D deficiency because of their problem of sun ray absorption. The darker the skin, the more sunlight is needed to generate vitamin D. A recent study from the Centers for Disease Control found that 40 percent of black women had insufficient levels of it.

In regard to people who are substantially overweight, Vitamin D is a fat-soluble vitamin. It can get trapped in excess fat cells and not circulate through the blood. The obese typically have about two-thirds less vitamin D in their blood. Sandroff says that even people who are moderately overweight should make sure they are getting enough vitamin D.

She says the food that can help provide vitamin D are fatty fish and milk. Most people can take a supplement that includes 400 I.U. (international units) of vitamin D. People over 65 need between 600 to 800 I.U. in their vitamin D supplement. People at any age, who rarely get sun, need 1,000 I.U.'s. Sandroff warns that no one should take over 2,000 units.

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