Nearly half of seniors improve with age - and researchers think they know why

Aging is often depicted as a steady decline, but new research suggests that many older adults actually improve over time.

The improvements were consistent across the study population, and were linked to the participants' mindset about aging, according to a press release.

The research, which was published in the journal Geriatrics, relied on data from the Health and Retirement Study, a federally supported, long-running survey of older Americans.

Over a 12-year period, 45% of participants improved either mentally or physically. About 32% showed cognitive gains, while 28% improved physically, according to the study.

"If you average everyone together, you see decline," Levy said. "But when you look at individual trajectories, you uncover a very different story. A meaningful percentage of the older participants … got better."

"Individuals who have taken in more positive age beliefs ... tend to have a lower stress response and lower stress biomarkers," Levy said. Because age beliefs are modifiable, she noted, there could be a capacity for improvements later in life.

The study did have some limitations, the researchers acknowledged. It didn't look at how muscles or brain cells change and adapt, which could help explain why people improved.

Future studies should examine improvement patterns for other types of cognition, such as spatial memory, they added.

"In addition, although our participants were drawn from a nationally representative sample, it would be useful to examine patterns of improvement in additional cohorts that have a greater representation of different ethnic minority groups," the researchers noted in the study.

The authors said they hope the findings will debunk the myth that continuous physical and cognitive decline is inevitable.