Obesity and smoking causes US lag in life expectancy

Obesity and smoking rates were blamed in an American report on life expectancy that showed the U.S. trailing behind other nations despite higher health care costs.

A report by the National Academy of Sciences, commissioned by the U.S. government and widely reported Tuesday, showed that over the past 25 years, life expectancy after 50 had risen in the United States, but at a slower rate than in countries like Japan and Australia.

The study, which examined mortality records in 21 countries, found that American men could expect to live 5.5 years longer in 2006 than they did 25 years earlier, while women will live 3.2 years longer. But the gains lagged behind the improvement seen in 21 other countries, including Japan, France, Switzerland, New Zealand and Sweden.

The report recognized that public smoking is being stamped out in the U.S., while it's common in parts of Europe, concluding that the slower improvement in survival reflected cigarette consumption three to five decades ago, when more Americans smoked than elsewhere in the world.

There is a lag of two to three decades between smoking and its effect on death.

Thanks to the decline in smoking over the last 20 years, the life expectancy of U.S. men is expected to rapidly improve in coming decades. That improvement will be a little slower for U.S. women, whose peak smoking rates occurred several years after men's.

But the anticipated gains from reduced smoking rates may be eroded by increasing numbers of Americans who are overweight, obese and sedentary, the report found.

Excess weight may account for one-fifth to one-third of the discrepancy in survival gains between the U.S. and other high-income countries, the researchers said.

In the U.S., life expectancy at birth was 80.8 years for women and 75.6 years for men in 2007. In France, life expectancy for women was 84.4 years and 77.4 for men. And in Japan, it was nearly 86 years for women and 79.2 for men.