Lack of a high school education predicts a shorter lifespan, owing to a survey of mortality data in the US.
If you look at death rates, you'll find a big variation throughout the various US states. Professor Andreas Muller of the University of Arkansas at Little Rock has looked at data for all states for the years 1989 and 1990 and found that level of formal education is an important predictor of mortality.

Put simply, those lacking high school education are more likely to die young. The reasons are not hard to find. The less well-educated are less likely to have health insurance, they work in jobs with a high risk of injury, and they are more likely to smoke. All of these factors have a big impact on health and life expectancy. Raising education standards is likely to affect not just economic achievement, but how long you can expect to live.