In 1936, the Hungarian endocrinologist Hans Selye injected rats with a hormone from cow’s ovaries. Things did not go well. The lab rats developed bleeding ulcers.
Next, Hans injected the rats with a salt solution and a hormone isolated from a cow’s placenta. The rats developed the same symptoms. Next up was an injection made from kidneys and spleens, Kelly McGonigal writes in her book The Upside of Stress.
Same result: sick rats.
“Eventually, Selye had a flash of insight: The rats weren’t getting sick because of what they were injected with, but because of what they were experiencing,” Kelly writes. “Selye found that he could create the same symptoms by subjecting rats to any uncomfortable experience: exposing them to extreme heat or cold, forcing them to exercise without rest, blasting them with noise, giving them toxic drugs.”
The rats reminded Hans of his old human patients whose bodies were falling apart: “They seemed worn out and run down. At the time, Selye called it ‘sick syndrome’,” Kelly writes. “Perhaps, he reasoned, the cumulative wear and tear of life’s challenges weakened the body.”
This is how the science of stress began.
“Here is where Selye made the grand leap from rat experiments to human stress,” states Kelly. “He hypothesized that many conditions plaguing humans, from allergies to heart attacks, were the result of the process he had observed in his rats. Selye’s leap from rats to humans was theoretical, not experimental. He had studied lab animals all his life. But that didn’t keep him from speculating about humans.”
Hans then made another decision that forever changed how the world thought about stress, Kelly observes.
“He chose to define stress in a way that went far beyond his laboratory methods with rats. Stress, he claimed, was the response of the body to any demand made on it. It wasn’t just a response to noxious injections, traumatic injuries, or brutal laboratory conditions, but to anything that requires action or adaptation.
“By defining stress in this way, Selye set the stage for our modern terror about stress,” writes Kelly.
So, was Selye right?
Yes. And, no.
Kelly writes: “If you’re the human equivalent of Selye’s rats—deprived, tortured, or abused—then, yes, your body will pay a price. There is ample scientific evidence that severe or traumatic stress can harm your health. However, Selye defined stress so broadly that it includes not just trauma, violence, and abuse, but also just about everything that happens to you,” Kelly writes. “To Selye, stress was synonymous with the body’s reaction to life.”
Later in his life, Hans realized not all stressful experiences will make you sick. “He started talking about good stress (eustress) as an antidote to bad stress (distress),” writes Kelly. “He even tried to improve stress’s image, saying in a 1970s interview, ‘There is always stress, so the only point is to make sure that it is useful to yourself and useful to others.’
“But it was too late,” Kelly observes. “Selye’s work had already instilled a general fear about stress in the general public and the medical community.”
Reflection: How might I benefit from redefining my view of stress?
Action: Have a conversation with someone I’m close to about our experience with stress.