Most U.S. adults say they are in good or excellent health, according to a new Gallup poll. Of those polled, 79% rated their physical health as "excellent" or "good," while 21% said it was "only fair" or "poor." Self-ratings for mental health were even higher: 86% said their mental health was "excellent" or "good," while 14% rated it "only fair" or "poor."

Are Americans really as healthy as we claim? That's not clear. The poll didn't include specific health questions -- such as "What is your blood pressure?" -- and participants weren't asked for medical records for confirmation.

As for demographics, the analysis shows that younger adults, Republicans, men, people with higher incomes, whites, and churchgoers are most likely to rate their physical and mental health highly.