Why some stress is good for you

Shereen Dindar
Contributing Writer
Shine On

Gah, stress. Many of us view it as a necessary evil, a function of modern day living, similar to how we've come to accept chronic sleep deprivation.

How are we really expected to hold down a full-time job, commute in historically high levels of traffic, raise two kids who have after school activities and pay off a mortgage while caring for our aging parents.

Something's got to give. If it's not sleep, then perhaps our cortisol levels.

But now new research suggests that a moderate amount of stress can actually improve our cognitive functioning, rather than harm our health.

In a new study published in the online journal eLife researchers Daniela Kaufer and Elizabeth Kirby from the University of California, Berkeley suggest that not all stress is created equal.

Also see: Father's unexpected and touching response to his son coming out

“You always think about stress as a really bad thing,” says Kaufer, associate professor of integrative biology. "But some amounts of stress are good to push you just to the level of optimal alertness, behavioral and cognitive performance.”

Both women conducted their research on rats -- and while we all should know by now that research involving rats is far from fool proof -- there are some benefits known in the scientific community for using rats to test hypotheses.

The researchers found that significant, but brief periods of stressful events caused stem cells in the rats' brains to proliferate into new nerve cells that improved the rats’ mental performance two weeks later.

They were particularly interested in the relationship between stress and memory and examined how stress affected the hippocampus area of the brain, which is critical to memory.

“Intermittent stressful events are probably what keeps the brain more alert, and you perform better when you are alert,” says Kirby, a post doctoral fellow.

Also see: The secret to happiness? Believing you have more sex than your friends, study finds

In order to test their ideas, they subjected rats to short-lived stress – immobilizing them in their cages for a few hours. This led to the stress hormone cortisol reaching levels as high as those from chronic stress, though for only a few hours. But perhaps most interestingly, the stress doubled the proliferation of new brain cells in the hippocampus -- the area associated with memory.

"The study reinforces the notion that stress hormones help an animal adapt – after all, remembering the place where something stressful happened is beneficial to deal with future situations in the same place,” says scientist Bruce McEwen from Rockefella University, who was not involved in the study.

So while it is well known that chronically elevated levels the stress hormone cortisol can increase your risk of obesity, heart disease and depression, we might want to take pause at what just a bit of stress can do for us.

“Stress can be something that makes you better, but it is a question of how much, how long, and how you interpret it,” concludes Kaufer.