Among Vitamins, D Seems Short for 'Does a Lot' (2/2)

Small amounts of D are found in beef liver, cheese and egg yolks. And some people take dietary supplements containing the vitamin. But most of the vitamin D in the American diet comes from foods with D added, like milk.

In nineteen ninety-seven, the United States Institute of Medicine established levels for how much vitamin D healthy people need. It set the daily amount at two hundred international units from birth through age fifty. It set the level at four hundred I.U.s through age seventy, and six hundred for age seventy-one and older.

But some groups say these amounts are not high enough. They are hoping that the new research findings will lead to new recommendations.

Research in the last several years has shown that low levels of vitamin D may increase the risk of heart attacks in men and deaths from some cancers. Other studies have shown that people with rheumatic diseases often have low levels of vitamin D.

More doctors are now having their patients tested for their vitamin D levels. But as research continues, some experts worry that if people take too much vitamin D, it might act as a poison. Also, skin doctors warn people to be careful with sun exposure because of the risk of skin cancer.

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