Being put under pressure at home or at work is not such a bad thing – as long as it is the right amount.
Researchers claim it forms part of the cell’s survival strategy and can boost resilience, protect cells against ageing and staves off illness.
Chronic stress is known to increase the risk of heart attack – and has been linked to a host of other potentially fatal conditions by affecting the immune system.
But a little is good for health – and longevity, said molecular biologist Professor Richard Morimoto.
In experiments on worms his researchers found stress sensed in one part of a cell prevents the accumulation of damaged proteins linked to brain function decline and ageing.
The findings in the transparent roundworm C. elegans could have implications for humans and quality of life.
They shed fresh light on the molecular mechanisms that drive ageing and risk for Alzheimer’s disease and other age-associated illnesses.
Professor Morimoto and his colleagues showed signals from mildly stressed mitochondria – tiny bits of DNA that power cells – strengthen proteins that weaken over time.
This, in turn, suppresses damage that leads to a host of devastating illnesses including dementia, Huntington’s and Parkinson’s diseases and motor neurone disease.
Professor Morimoto, of Northwestern University in Illinois, said the long-term goal is to match good cellular and molecular health with lifespan.
“This has not been seen before. People have always known prolonged mitochondrial stress can be deleterious. But we discovered when you stress mitochondria just a little the mitochondrial stress signal is actually interpreted by the cell and animal as a survival strategy.
“It makes the animals completely stress-resistant and doubles their lifespan. It’s like magic,” he said.
Components identified by scientists as playing a role in biological ageing are conserved in all animals – including humans – and offer targets for future study.
Professor Morimoto said: “Our findings offer us a strategy for looking at ageing in humans and how we might prevent or stabilise against molecular decline as we age.
“Our goal is not trying to find ways to make people live longer but rather to increase health at the cellular and molecular levels – so a person’s span of good health matches their lifespan.”
Professor Morimoto added: “I never would have guessed this – a low stress signal resets the organismal lifespan profoundly.
“What we are learning is some of these stress signals are interpreted by the organism as a way to reset itself and to live longer.
“When mitochondria function optimally the cells and tissue are robust.”
Research has shown almost half of Britons consider themselves stressed – reducing levels is the one thing they would most like to change about their lives.
But research is growing that it can be a good thing – as long as it’s not too much.
It is known chronically elevated levels of stress hormones increasing the risk of obesity, heart disease and depression.