Vitamin A may play a role in reducing the rate of breast cancer growth, working to limit cell proliferation, according to a new study.

Current therapies for the disease rely on blocking the effects of the hormone estrogen, which promotes the growth of cells in the breast that can include cancerous growths.

Now scientists at the University of Chicago say that retinoic acid, one of the compounds in the vitamin, may also benefit women who need treatment for the disease because the acid also plays a role in regulating cell growth and blocking the effects of estrogen on tumor expansion.

Although they say that more research would be necessary to find a therapy, in an accompanying editorial, Dr Myles Brown said the "insights will hopefully lead to new approaches for the prevention and treatment of the most common form of breast cancer."

Other chemicals found in vitamin A may also benefit women by increasing bone strength, according to a study released from Tufts University.

Supplements that include carotenoids found in the nutrient were linked to increased bone density by researchers there.