The average low-income person loses 8.2 years of perfect health, the average high school dropout辍学 loses 5.1 years, and the obese²肥胖的 lose 4.2 years, according to researchers at Columbia University's Mailman School of Public Health. Tobacco control has long been one of the most important public health policies, and rightly so; the average smoker³ loses 6.6 years of perfect health to their habit. But the nation's huge high school dropout¹ rate and poverty rates are typically not seen as health problems. This new study published in the December 2009 issue of the American Journal of Public Health, shows that poverty and dropout rates are at least as important a health problem as smoking in the United States.

These researchers define "low-income" as household earnings⁴ below 200% of the Federal Poverty Line, or roughly the bottom third of the U.S. population.

On average, poverty showed the greatest impact on health. Smoking was second, followed by being a high school dropout, non-Hispanic Black, obese, a binge drinker酗酒, and uninsured. The findings are based on data from various national datasets that are designed to measure both health and life expectancy平均寿命，预期寿命. Healthy life lost combines both health and life expectancy⁵ into a single number, sometimes known as quality-adjusted life years.

"While public health policy needs to continue its focus on risky⁶ health behaviors and obesity⁷, it should redouble its efforts on non-medical factors, such as high school graduation and poverty reduction programs," according to Peter Muennig, MD, assistant professor of health policy and management at the Mailman School of Public Health and principal investigator⁸ of the study. Specific policies that have proven successful in the past include reduced class size in grades K-3 and earned income tax credit programs, according to Dr. Muennig.

To analyze⁹ the medical and non-medical policies that might affect population health, the researchers examined such policy goals as smoking prevention, increased access to medical care, poverty reduction, and early childhood education to provide policymakers with a sense of how different policy priorities might influence population health.

Building on prior research, the researchers examined health disparities不等，不同 resulting from an individual's membership in a socially identifiable and disadvantaged group compared with membership in a non-disadvantaged counterpart. Although public health policy has always been directed at individual social and behavioral risks, until now there had been little systematic¹⁰ investigation¹¹ of their relative contribution to U.S. population health. The researchers were not able to capture all population health risks. For instance, they did not include an analysis of transportation policy, which can affect health through reduced accidents, reduced pollution, and increased exercise.

"The smaller impact of schooling¹² in our analyses probably had a lot to do with the fact that we are only measuring the health of people in the general population. We miss those in prisons and chronic¹³ care facilities, most of whom lack a high school diploma. If we captured these individuals, the numbers would be higher.

"As with other burden of disease studies, the policies we identify will not eliminate the risk factor in the population; our estimates can only serve as guideposts for policymakers," says Dr. Muennig.