New Research Shows Americans Living Longer Due to Decline in Smoking

July 01, 2011
Lebanon, NH

Samir Soneji, PhD

Samir Soneji, PhD

Implications for Possible Net Loss to Social Security

Americans are living longer than currently projected by the U.S. Census and Social Security Administration because of the steady decline in smoking, according to a new study co-authored by Dartmouth Assistant Professor Samir Soneji, PhD, who is a member of Dartmouth-Hitchcock Norris Cotton Cancer Center's Cancer Control research program.

Although decreased mortality is a victory in many ways, the increase in life expectancy could possibly mean a net loss for the Social Security Administration because as we live longer, there will be fewer workers to support such entitlement programs, write Soneji and co-author Gary King of Harvard University.

In the article, titled, "Future of Death in America," the researchers estimate an increase in male life expectancy at birth from 76.2 years in 2010 to 79.9 years in 2030. This is 1.8 years greater than the Social Security Administration projection and 1.5 years more than the U.S. Census projections.

Women had more modest gains in life expectancy, from 80.5 in 2010 to 81.9 years in 2030, virtually identical to the Social Security projection and two years less than U.S. Census projections.

The difference in the projections is because Soneji and King included smoking and obesity rates in their mortality forecasts. This study marks the first time those factors have been included directly.

"Smoking and obesity are two important risk factors, with well-studied consequences for mortality and large changes over time, and that is why those two variables were included," said Soneji. And, he said, while smoking rates have steadily decreased over the last half century, obesity rates have risen, particularly in the last 30 years. "Our gains in life expectancy because of decreased smoking may in fact be reversed in coming years because of the profound increase in obesity in the United States."

The potential challenge for Social Security, Medicare and other entitlement programs is that while U.S. life expectancy continues to rise, the working population is decreasing. U.S. life expectancy has grown from 68 to 78 years since 1950, meaning those over 65 now make up 19 percent of the country's population – up from 14 percent in 1950. At the same time, the working population (those 18 to 64) has declined from 60 to 56 percent.

These factors could have "massive implications for American life," said Soneji. Aside from Social Security, pension programs, economic growth, health care financing, public health efforts and research programs could be affected.

Net gains or losses to Social Security and Medicare remain open questions because of obesity related mortality, the researchers said. This is because of illnesses related to obesity, early work disability, earnings, and death before and after retirement age.

Dr. Soneji has dual faculty appointments at Dartmouth. He is a faculty member with The Dartmouth Institute for Health Policy and Clinical Practice and with Norris Cotton Cancer Center.

This research can be found in Demographic Research, the online journal of peer-reviewed research and commentary in the population sciences published by the Max Planck Institute for Demographic Research in Germany. A link to the full study may be found at

About Dartmouth-Hitchcock Norris Cotton Cancer Center
Norris Cotton Cancer Center combines advanced cancer research at Dartmouth College and Dartmouth Medical School with patient-centered cancer care provided at Dartmouth-Hitchcock Medical Center, at Dartmouth-Hitchcock regional locations in Manchester and Keene, NH, and St. Johnsbury, VT, and at 11 partner hospitals throughout New Hampshire and Vermont. It is recognized and designated by the National Cancer Institute for its breadth and depth as one of just 40 Comprehensive Cancer Centers in the U.S. Learn more about Norris Cotton Cancer Center research, programs, and clinical trials online at

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