In a survey of 1,000 adults, the Cleveland Clinic learned that three out of four don't think they'll die of heart disease, even though it is the leading killer in this country.
Another mistaken belief they found is that many people trust that vitamins will reduce their risk of heart trouble.
The Cleveland Clinic says that has never been proven. Most indicated they don't believe salt is a big concern for them, but overall, the fact is most of us are eating much more salt than we think we are.
"There's a lot of hidden sources of sodium in the diet, including things like breads, that we don't recognize," says Dr. Richard Krasuski with the Cleveland Clinic.
The survey also found people are mostly unaware of important numbers they should know, for their personal blood pressure, cholesterol, body mass index, waist circumference and blood sugar.
And perhaps the biggest surprise researchers found, is that many Americans still don't know realize exercise can cut your risk of dying from heart disease in half, and that quitting smoking provides an almost immediate heart benefit that only gets better with time.