High doses of antioxidant nutritional supplements, such as vitamins C and E, can increase genetic abnormalities in cells, which may predispose supplement-takers to developing cancer, according to a new study from the Cedars-Sinai Heart Institute.
The study, led by Eduardo Marbán, M.D., Ph.D., director of the Cedars-Sinai Heart Institute, was published online in the medical journal Stem Cells. The study also will appear in the journal's July printed edition.
Marbán and his team accidentally discovered the danger of excessive antioxidant doses while seeking a way to reduce the genetic abnormalities that occurred naturally when the scientists sought to multiply human cardiac stem cells.
Marbán stressed that the study's finding applies only to excessive nutritional supplements and not to foods that are rich in antioxidants, such as milk, oranges, blueberries and peanuts. In recent years, multiple studies have touted the benefits of foods rich in antioxidants.
"Taking one multivitamin daily is fine, but a lot of people take way too much because they think if a little is good, a lot must be better," said Marbán, who is also the Mark Siegel Family Professor at Cedars-Sinai. "That is just not the case. If you are taking 10 or 100 times the amount in a daily multivitamin, you may be predisposing your cells to developing cancer, therefore doing yourself more harm than good."