The "sunshine vitamin," may lower risk of breast cancer

Women who get lots of vitamin D are less likely to develop breast cancer, suggests a pair of studies that add to the already strong evidence that the "sunshine vitamin" helps prevent many types of cancer.

High levels of vitamin D translated to a 50 percent lower risk of breast cancer, one study found. Even modestly higher levels resulted in 10 percent less risk, which would translate to 20,000 fewer cases a year if it were true of all American women.

A second study, by Canadian researchers, found that women who spent time outdoors or got a lot of vitamin D from their diets or supplements especially as teens were 25 percent to 45 percent less likely to develop breast cancer than women with less of the nutrient.

"Exposure to vitamin D at the time breasts are developing, particularly around adolescence, might be important," said lead researcher Julia Knight of Mount Sinai Hospital in Toronto.

Both studies were presented Tuesday at a meeting of the American Association for Cancer Research.

The body makes vitamin D from sunlight, but sun exposure is controversial because of the risk of skin cancer. Many health experts see little harm in 15 minutes several times a week.

Vitamin D is found in salmon, tuna and other oily fish, and is routinely added to milk, but diet accounts for very little of the nutrient that actually makes it into the bloodstream.

Supplements contain the nutrient, but most contain an old form, D-2, that is less potent than the harder-to-find D-3. Multivitamins typically contain little D-2 and include vitamin A, which offsets many of D's benefits.

So getting enough D safely and effectively is tough, but important, as the new studies show, reports AP.

O.Ch.