As people get older, it’s natural for their memory and thinking skills to slowly decline.
But new research from Penn State suggests that weight loss or frequent weight changes in adults over 65 may make that decline happen faster.
The study, published in the journal Obesity, analyzed 11 years of health data from more than 4,300 older adults who took part in the National Health and Aging Trends Study.
Researchers tracked not only body weight but also body mass index (BMI) and waist size, while also testing memory, orientation, and decision-making skills.
“We looked at the data in three different ways, and the message was always the same,” said Muzi Na, associate professor of nutritional sciences and senior author of the study. “The more a person’s weight changed from year to year, the faster their cognitive abilities declined.”
Participants were grouped according to how much their weight shifted over the 11 years. Those whose weight remained steady showed the slowest mental decline, while those with the most weight fluctuations experienced two to four times as much decline. Similar patterns were seen with BMI and waist measurements.
The researchers also studied specific patterns of weight change. Losing at least 5% of body weight, or cycling between losing and gaining at least 5%, was linked to faster decline in thinking and memory. Weight gain alone, however, showed about the same rate of decline as stable weight.
Still, the researchers caution that this does not mean gaining weight in old age is protective. “We know that obesity in middle age is a risk factor for dementia later in life,” Na explained.
“But in older adults, the picture is more complicated. Some studies suggest that fat gain combined with age-related muscle loss may create what looks like a protective effect. Our study does not recommend that older adults try to gain weight.”
Instead, the findings highlight the importance of monitoring weight closely in later life. Sudden or ongoing weight loss in older adults could be an early warning sign of faster cognitive decline and should not be ignored.
Na suggests that older adults track their weight at home in a consistent way, since doctor’s office measurements can vary. “One time you might be weighed in heavy shoes and a coat, another time in light clothes. To really understand changes, weigh yourself at the same time each morning, after using the bathroom and before breakfast, wearing the same pajamas. That gives much more reliable data,” Na said.
If an older adult notices their weight is not stable, they should share this information with their doctor. Keeping weight steady may not prevent memory decline altogether, but it could help slow down the process and protect brain health for longer.
If you care about brain health, please read studies about the likely cause of Alzheimer’s disease , and new non-drug treatment that could help prevent Alzheimer’s.
For more health information, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
