Why Americans' Life Expectancy Is Getting Longer

A study from the University of Southern California (USC) and Yale University published in Demography found Americans appear to be aging slower than before, which may help explain recent increases in life expectancy, reports HealthDay News . The researchers compared how biological age changed in the United States compared to chronological age, investigating national health surveys conducted in 1988-1994 and 2007-2010. "This is the first evidence we have of delayed 'aging' among a national sample of Americans," says USC Professor Eileen Crimmins. Older adults had the highest gains in biological age, while men experienced greater declines than women. These differences were partly accounted for by changes in smoking, obesity rates, and medication use. "While improvements may take time to manifest, and thus are more apparent at older ages, this could also signal problems for younger cohorts, particularly females, who — if their improvements are more minimal — may not see the same gains in life expectancy as experienced by the generations that came before them," says Yale University Professor Morgan Levine. The researchers also observed that the pace of aging and increasing longevity could have major social and economic ramifications. "Life extension without changing the aging rate will have detrimental implications," Levine warns. "Medical care costs will rise, as people spend a higher proportion of their lives with disease and disability."