Popping vitamins may do more harm than good, according to a new study that adds to a growing body of evidence suggesting some supplements may have health risks. Researchers from the University of Minnesota examined data from more than 38,000 women taking part in the Iowa Women's Health Study, an ongoing study with women who were around age 62 at its start in 1986. The researchers collected data on the women's supplement use in 1986, 1997 and 2004.
