Vitamins and Supplements. An illustration of how a bubble is burst.

A Scientist Debunks The 'Magic' Of Vitamins  And Supplements

"If you take large quantities of vitamin A, vtamin E, beta carotene [or] selenium you increase your risk of cancer, risk of heart disease, and you could shorten your life," says Dr. Paul Offit, a researcher at The Children's Hospital of Philadelphia.

Many large studies in recent years have shown that vitamins and dietary supplements rarely help and often hurt, Offit says. Yet a huge number of people still believe that these products will improve their health. So, Offit says, he decided to challenge the false beliefs of "the church of vitamins and supplements."