Stress can literally shrink your brain, study finds

MINNEAPOLIS — Stressed and want a good reason to decompress? Maintaining a healthy blood pressure is a given, but now you have yet another reason to do what it takes to relax. A recent study finds chilling out isn’t just an indulgence: according to researchers, stress not only impairs memory, but actually decreases brain size.

The study, published in the journal Neurology, comes after researchers studied 2,231 middle-aged participants in the famous Framingham Heart Study. In addition to finding a correlation between high levels of the stress hormone cortisol and memory impairment, the researchers also found via MRI scans that those with heightened cortisol had decreased brain volume.

“In our quest to understand cognitive aging, one of the factors attracting significant interest and concern is the increasing stress of modern life,” says the study’s senior author Dr. Sudha Seshadri, in a news release. “One of the things we know in animals is that stress can lead to cognitive decline. In this study, higher morning cortisol levels in a large sample of people were associated with worse brain structure and cognition.”

Seshadri, a professor of neurology at UT Health San Antonio and founding director of the university’s Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, says the fast pace of modern life seems to frequently trigger our flight-or-fight response.

“When we are afraid, when we are threatened in any way, our cortisol levels go up,” she says. “This study adds to the prevailing wisdom that it’s never too early to be mindful of reducing stress.”

In a separate release, another of the study’s authors, Harvard Medical School’s Dr. Justin Echouffo-Tcheugui, added that their research detected memory impairment and brain shrinkage well before symptoms started to show.

“…so it’s important for people to find ways to reduce stress, such as getting enough sleep, engaging in moderate exercise, incorporating relaxation techniques into their daily lives, or asking their doctor about their cortisol levels and taking a cortisol-reducing medication if needed,” he says. “It’s important for physicians to counsel all people with higher cortisol levels.”

The researchers also noted that there were some limits to their study: cortisol levels were only measured once and the majority of the participants were middle-aged and of European ancestry. Accordingly, there is still more to investigate about long-term exposure to cortisol and its effects on a broader range of people.