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Studies show vitamin D can help fight cancer

February 22, 2010 12:00:00 AM PST
Vitamin D is known for building strong bones. And there are many studies showing it can fight off a host of diseases, as well. New research suggests vitamin D might actually hold the key to fighting cancer.The evidence is mounting, low levels of vitamin D has been linked to breast, colon and prostate cancers to multiple sclerosis and heart disease.

"I even think of vitamin D as the fountain of youth, if you will, in that it allows us to age well," said professor Mark Haussler of the University of Arizona College of Medicine.

When researchers from State University of N.Y., Albany, added a potent form of vitamin D to breast cancer cells in the lab, within four days, half the cancer cells were dead.

"What happens is that vitamin D enters the cells and it triggers the cell death process," said professor Joellen Welsh, of State Univ. of NY, Albany. "It's similar to what we see when we treat cells with Tamoxifen."

When researchers took human breast cancer cells and injected them into mice, tumors began to grow. But when the mice were given vitamin D, the tumors began to shrink. One tumor reduced by half, and another disappeared entirely. But the real test will be to see if vitamin D will work the same way in people.

Roger Clemens is a toxicologist at USC. He says the current data suggests that about 70 to 80 percent of the U.S. population is vitamin D deficient.

Based on his own research he believes vitamin D can do more for the body than just help with thinning bones.

"In hypertension, blood pressure regulation, heart health maintaining bone structure, as well as maybe being part of the obesity and diabetes story," said Clemens.

Other research echoes this same idea. It shows vitamin D can improve the way cells function in the heart and in blood vessels.

"The number one killer is vascular disease and vitamin D makes our arteries healthier, it basically allows them to age well," said Haussler.

While the research may still be preliminary it shows vitamin D may have a lot of potential.

So how much vitamin D should a person take? The federal guidelines say 400 units a day, but some research suggests people should take upwards of a 1,000.

Other experts say not so fast. It's possible vitamin D requirements may be based on a person's weight, percentage of fat and diet. It's always best to consult your doctor.