Stress can do odd things to your body. It can cause headaches, chest pains, fatigue, and digestive issues. According to new research, stress is also bad for your brain.
In a new study, published in the journal Neurology, people with higher levels of cortisol in their blood — the stress hormone — had impaired memories and smaller brains.
Researchers from Harvard Medical School recruited over 2,000 people with an average age of 49, and tested their memory and thinking skills. They also took blood samples and measured brain volume using an MRI.
A normal cortisol range was between 10.8 and 15.8 micrograms per deciliter, and researchers divided the participants into three groups: low, middle, and high level.
Results showed that people with high levels of cortisol had lower scores on memory and thinking skill tests than those with normal levels. Higher cortisol was also linked to having a slightly lower total brain volume; 88.5% of total cranial volume compared to 88.7%. There was no significant link between low cortisol levels and memory or brain size.
“Cortisol affects many different functions so it is important to fully investigate how high levels of the hormone may affect the brain,” said Justin B. Echouffo-Tcheugui, lead author of the study and doctor at Harvard.
“Our research detected memory loss and brain shrinkage in middle-aged people 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.”
In 2014, a study from the University of California, Berkeley found that chronic stress can cause long-term changes in brain structure and function, which may make people more prone to anxiety and mood disorders.
The researchers discovered that chronic stress generates myelin-producing cells and fewer neurons than normal, resulting in an excess of myelin, and white matter, in some areas.
White matter is made up of fibers that connect neurons to each other, so regions of the brain can better communicate. It’s the gray matter which is full of nerve cells and is used for thinking, computing, and decision making. Both are important, but an excess of white matter might mean there is less room for the higher functions.
Co-author of the new study Sudha Seshadri told Time that witnessing how cortisol can change brain function is both “alarming and an opportunity.” One reason, she said, is because cognitive decline could be a precursor for dementia.
“There’s one more strand that one can work on to reduce the public health impact of dementia,” she said. “I cannot tell you for sure that lowering cortisol is going to necessarily result in benefits, but it’s a first step.”
Originally published at www.thisisinsider.com
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