ISLAMABAD, November 24 (Online): Whatever doesn’t kill you makes you stronger,” goes the phrase. And somehow, we all actually believe it.
We humble brag that we’re stressed about work, our families, our finances, and how hard and time-consuming it is to plow through everything on our vast and daily to-do lists. We’re super stressed about politics, natural disasters, climate change — even who will win the Super Bowl.
Stress may be an unavoidable part of life, but when you get stressed and stay stressed, it’s no badge of honor. Think of the last prolonged stressful situation you were in. Not something that lasted an hour or two, like a root canal at the dentist’s office, but one that lasted weeks, months, or even years: a high-intensity job with a ruthless boss, for instance, or caring for a sick parent.
During that time, did you eventually find it harder to make simple decisions, remember the right word for something, or just keep track of your car keys?
At the time, it might have felt like the universe was conspiring against you. But there’s a scientific reason for what was more likely happening: Stress has the ability to physically shrink your brain.
When you get stressed, your body releases cortisol, aka the stress hormone. In limited bursts, this isn’t a bad thing. Cortisol has the power to lower your blood pressure, manage your blood sugar, and reduce inflammation within the body.
Researchers at the University of California at Berkeley even found that when lab rats were exposed to brief stressful events (“brief” being the operative word), stem cells in their brains actually bloomed into new nerve cells. As a result, the rats’ mental performance improved. But chronic stress — that is, repeated and prolonged exposure to something stressful, like the demanding job or gravely ill parent mentioned above — doesn’t offer the same perks.
Over long periods of time, elevated levels of cortisol can push you further down the road toward obesity, heart disease, depression, high blood pressure, and unhealthy lifestyle behaviors. There’s proof it takes a toll on your gray matter as well.
“High cortisol levels secreted due to stress damage and reduce the volume of the brain,” said Dr. Janette Nesheiwat, a board-certified family and emergency medicine doctor in New York City. “We can see this on scans of the brain.” Two areas affected are the hippocampus, which plays a central role in learning and memory, and the prefrontal cortex, which regulates thoughts, emotions, and actions by “talking” to other brain regions.
In a recent study published online in the journal Neurology, researchers checked cortisol levels in the blood of 2,231 healthy middle-aged people. They also assessed their memory and thinking skills and took images of their brains.
What they found was that participants — particularly women — who had high levels of cortisol in their blood did poorer on memory and cognitive tests. Over time, they also appeared to lose brain volume.
So, should these study results serve as a wake-up call that our stressful, “I’ll sleep when I die” lifestyle may not be worth the long-term costs? Yes, says Seshadri, adding this even includes herself.
Yet before you stress about your brain shrinking, keep in mind that it’s unclear whether this change is permanent. When Starkman’s patients were studied a year after their treatment for Cushing disease (which usually consists of pituitary surgery), their cortisol levels had gone down and the volume of the hippocampus increased.
“Their scores in learning increased as well,” Starkman said. We also know that a person’s memory performance can improve, points out Seshadri. “Reducing stress might [also] help, but the only way to be sure is through clinical trials, and these have not yet been done,” she said.