Do you know these risk factors for heart disease? Many Americans don't, survey finds.

Many Americans are unaware of the risk factors for heart disease, according to a recent survey from the Cleveland Clinic. 

In the national survey, 40% of respondents didn't know using tobacco impacts heart health, 62% didn't know air pollution harms the heart and 90% weren't aware certain supplements and vitamins can affect the heart. 

"Many of us think about vitamins or supplements over the counter as natural. And some may even consider them preferable alternatives to prescription medications, but research doesn't back that up," Cleveland Clinic's Dr. Ashish Sarraju told CBS News.