The good news is you might live longer than you expect. The bad news is that such inaccurate estimates could cause you to skip lifestyle changes that can make your remaining years healthier and more independent. Researchers at the University of California-San Francisco report that 33% of the more than 2,000 adults ages 64 and older they surveyed underestimated their likely longevity. Participants were asked to estimate their odds of living at least another 10 years; responses were then compared to objective calculations used to predict clinical outcomes. Overall, 55% guessed similarly to their calculated longevity, while 12% overestimated lifespans. Results were published in JAMA Internal Medicine.