Nearly half of adults over age 65 got measurably better over time, according to a long-term study out of Yale University. The findings challenge the widespread belief that aging means steady, unavoidable decline.
The research, published in the journal Geriatrics and reported by Science Daily, drew on more than a decade of data from the Health and Retirement Study, a federally funded national survey. Researchers tracked more than 11,000 older Americans for as long as 12 years, measuring changes in both cognitive function and physical ability.
By the end of the study period, 45 percent of participants had improved in at least one area. About 32 percent showed cognitive gains, while 28 percent improved physically. Many of those improvements were large enough to be considered clinically meaningful by researchers. When participants whose cognitive abilities stayed stable were included alongside those who improved, more than half of the group avoided the cognitive decline most people expect from aging.
Physical function was measured using walking speed, which geriatricians consider a key indicator of overall health because of its links to disability, hospitalization, and mortality.
"Many people equate aging with an inevitable and continuous loss of physical and cognitive abilities," said Becca R. Levy, lead author of the study and professor of social and behavioral sciences at the Yale School of Public Health. "What we found is that improvement in later life is not rare, it's common, and it should be included in our understanding of the aging process."
One reason the gains have gone unnoticed, Levy said, is the way data is typically analyzed. Looking at group averages tends to mask what is happening to individuals. "What's striking is that these gains disappear when you only look at averages," she said. "If you average everyone together, you see decline. But when you look at individual trajectories, you uncover a very different story. A meaningful percentage of the older participants that we studied got better."
The research team also examined why some participants improved while others did not. One factor they investigated was the attitude people held about aging at the start of the study. Those who began with more positive beliefs about getting older were significantly more likely to show improvements over time.
Levy is also the author of the book Breaking the Age Code: How Your Beliefs About Aging Determine How Long & How Well You Live. The study was supported by funding from the National Institute on Aging.
The researchers said the findings suggest that improvement in later life is far more common than previously understood and should be factored into how scientists, doctors, and the public think about what aging actually looks like.
