The damage caused by cigarette smoking was estimated to account for 78% of the gap in life expectancy for women and 41% of the gap for men between the United States and other industrialized countries in 2003, according to the NRC report.
Fifty years ago, more people smoked in the U.S. and smoked more intensively than in Europe or Japan, which helped suppress American life-expectancy gains over the last 25 years — there's a two- or three-decade lag between smoking and its peak effects on mortality. Meanwhile, the health effects of all that smoking in the 1950s and '60s are still playing out in the form of current lung cancer, heart disease and other illnesses for which tobacco is a contributing factor.
On the upside, Americans are about to begin reaping the benefits of recent reductions in smoking — during the 1970s, cigarette use began to decline in most high-income countries, but that decline was steeper in the U.S. than in most of Europe, particularly among men, according to the report. So life expectancy for U.S. men is likely to improve relatively rapidly in the coming decades. For U.S. women, however, among whom smoking rates peaked later than among men, increases in longevity are likely to lag for about another decade. (More on Time.com:Declines in U.S. Smoking Rates Remain Stalled at 20%)
Similarly, life expectancy in Japan is predicted to increase more slowly than it otherwise might have, because of more recent, higher smoking rates.
On average Americans don’t live as long as people in many other wealthy nations, and they’re less healthy overall — this, despite the fact that the U.S. spends more on health care than any other nation in the world. A new report by the National Research Council lays out the reasons for America’s longevity problem, but also indicates that the U.S. is poised to gain ground.