The Impact of Behavioral Change on Life Expectancy

American life expectancy is rising. The increase is due in part to better medications and improved medical interventions. It's also due to changes in behavior. How much has good behavior by the American public contributed to the rise in life expectancy over the past half century? How much has bad behavior limited the rise? Those questions have now been answered by researchers at the National Bureau of Economic Research.

Between 1960 and 2010, life expectancy at birth in the U.S. grew 6.9 years. To determine how much of that rise was due to behavioral change, the researchers examined the impact on life expectancy of six factors: smoking, drinking, motor vehicle fatalities, obesity, poisonings, and firearms. Here's how changes in each of those behaviors affected life expectancy over the past half century...

Impact on life expectancy (in years)
+1.26 years from less smoking
+0.43 years from safer motor vehicles
+0.06 years from less heavy drinking
-1.00 years from more obesity
-0.26 years from more drug overdoses
-0.03 years from more firearm deaths

The gains from good behavior were nearly offset by declines due to bad behavior. Nevertheless, the researchers conclude, "our study demonstrates the enormous benefits of public health and behavior change in improving population health."

Source: National Bureau of Economic Research, How Behavioral Changes Have Affected U.S. Population Health Since 1960, NBER Working Paper #20631