The research was funded by funds from the National Institute on Aging.
Drawing on more than a decade of data from a large, nationally representative study of older Americans, researchers found that nearly half of adults age 65 and older experienced measurable improvements in cognitive function, physical function, or both.
The findings suggest that improvement in old age is much more common than many people believe.
“Many people equate aging with an inevitable and ongoing 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 (YSPH). “What we found is that improvement in old age is not rare, it is common and should be included in our understanding of the aging process.”
The study was published in the journal Geriatrics.
Aging and improvement over time
The research team analyzed data from more than 11,000 participants in the Health and Retirement Study, a federally funded, long-term survey of older Americans.
To measure changes in mental abilities, the researchers used a global cognitive assessment. Physical function was assessed through walking speed, a measure that geriatricians often consider a key indicator of general health because it is closely related to disability, hospitalization and mortality.
Participants were followed for up to 12 years. During that period, 45% showed improvements in at least one of the two areas examined.
Approximately 32% improved cognitively, while 28% improved physically. Many participants experienced gains large enough to be considered clinically significant. When the researchers also counted individuals whose cognitive abilities remained stable rather than declining, more than half of the participants avoided the common expectation of cognitive decline.
“The surprising thing is that these gains disappear when you just look at the averages,” said Levy, author of the book. Breaking the Age Code: How Your Beliefs About Aging Determine How Long and How Well You Live. “If you average them all together, you see a decline. But when you look at individual trajectories, you discover a very different story. A significant percentage of the older participants we studied improved.”
The role of positive beliefs about age
The researchers also explored why some older adults improved while others did not.
One possibility, they proposed, was the influence of beliefs about age held at the beginning of the study. Specifically, they examined whether participants had adopted more positive or more negative views about aging.
Their analysis supported that idea. Older adults with more positive beliefs about aging were significantly more likely to improve in both cognitive performance and walking speed. The relationship remained strong even after adjusting for factors such as age, sex, education, chronic diseases, depression, and length of follow-up.
The findings are based on Levy’s stereotype embodiment theory. The theory proposes that age-related stereotypes absorbed from society through sources such as social media and advertising can eventually become personally significant and have measurable biological effects.
Previous studies led by Levy found that negative beliefs about aging are associated with worse memory, slower walking speed, increased cardiovascular risk, and biomarkers related to Alzheimer’s disease.
According to Levy, the new findings show that the opposite pattern can also occur.
The current study shows that those who have assimilated more positive beliefs about age often show improvements, Levy said.
“Our findings suggest that there is often a reserve of capacity for improvement in old age,” he said. “And since beliefs about age are modifiable, this opens the door to interventions at both the individual and societal levels.”
Challenging assumptions about aging
The improvements were not limited to people who began the study with physical or cognitive disabilities.
The researchers found that even participants who started with normal levels of cognitive and physical function often improved over time. This finding challenges the idea that gains in old age simply reflect recovery from illness or a return to previous levels after a setback.
The authors hope the results will help change public perceptions about aging and reduce the belief that continued decline is inevitable. They also suggest that the findings support greater investment in preventive care, rehabilitation programs, and other health-promoting services that help older adults build resilience and improvement.
Martin Slade, professor of occupational medicine at Yale School of Medicine and YSPH Department of Environmental Health Sciences, was a co-author of the study.
The research was funded by funds from the National Institute on Aging.