Can stress actually be good for our health? The surprising ways it can make us stronger and boost longevity

How often do you get stressed? Maybe it’s time to up the frequency. This may sound counterintuitive but there’s a growing body of research that says that exposing ourselves to short, sharp bouts of stress is good for our health. It increases our resilience, can protect us against disease and can even help us live longer, healthier lives. It’s a biological phenomenon known as hormesis or hormetic stress and, simply put, is the principle that what doesn't kill you makes you stronger… up to a point.

That’s because there's a sweet spot: too much of the stressor and it's negative but just the right amount will stimulate a protective or beneficial response and your body will adapt to the new challenge. It's things like cold plunges, hot saunas, high-intensity work-outs (read about London’s toughest workouts here), intermittent fasting and even eating foods that are high in natural plant chemicals. These things put the body under stress but when done for just the right amount of time, help us to grow stronger – in the same way that getting a flu jab does.

What makes hormesis so remarkable is that the adaptation doesn’t just ready you for the particular stressor, e.g. cold water swimming, it prepares you, both mentally and physically, for other stressful events – even things like heart attacks. “We know that folk who have been exposed to hormetic stress and have adapted do better when it comes to any kind of extreme cardiac stress,” says Dr Jack Kreindler, founder of WellFounded, a company that researches resilience and longevity and offers health programmes.

“Instead of panicking and producing things that are bad for the body, they’re much more resilient and have better outcomes. Another example is adapting to altitude. When these people have an operation where their oxygen levels go down they fare better.

“There are real world advantages to being adapted or being fit. A tree doesn’t grow strong and resilient until it’s pushed about by the wind.”. Being “fit” or “fitting to the environment” is a key way to think about this concept, says Dr Kreindler. “Exercise is stressful on your muscles, hearts and lungs and creates a drop in oxygen,” he says. “But this stress helps to condition your muscles and your cells to work more efficiently – to fit to the new stressful environment.”.

The same thing applies to the brain and cognitive tasks. “If you take up a challenge like learning the piano or a new language that stress will literally cause a rewiring of the brain to be able to fit to the new environment,” says Dr Kreindler. Interestingly, even the food we eat can give us this kind of “good stress”. “Specific dietary components play a critical role in triggering hormetic responses,” says Dr Federica Amati, Head Nutritionist at ZOE and Nutrition Lead at Imperial College London.

“Phytochemicals — compounds found in plant-based foods — such as sulforaphane from cruciferous vegetables, curcumin from turmeric, allicin from garlic, capsaicin from chili peppers, and resveratrol from grapes” can all support cellular repair and reduce the risk of chronic diseases, Dr Amati explains. “Similarly, xenohormetic compounds, like resveratrol, have been shown to activate sirtuins (proteins linked to longevity) — thereby mitigating age-related decline and enhancing stress adaptation.”.

Vitamins and minerals also exhibit hormetic effects and are bound by a sweet spot. “Optimal levels are beneficial but excessive intake can become harmful,” says Dr Amati. “This underscores the importance of balanced nutrition rather than over-supplementation. Additionally, certain low doses of compounds like alcohol and even some natural pesticides can elicit mild stress responses that fortify cellular resilience. However, these should be approached with caution, as the threshold between beneficial and harmful exposure is delicate.”.

One of the best researched areas of dietary hormesis is caloric restriction and fasting. Multiple studies have shown that eating less, while still getting the required nutrients, extends the lifespan of many different types of animals. Human studies have also shown protective benefits and reduced risk of age-related diseases. “This is largely due to the activation of stress response pathways that enhance cellular resilience,” says Dr Amati. “Dietary restriction serves as a mild stressor, prompting the body to bolster its defenses against more severe challenges, thereby promoting longevity and metabolic health.”.

How do we know where the sweet spot is when it comes to “good stress”?. One of the challenges is that modern life is very comfortable, says Dr Kreindler. “Our homes are warm, we can get around without having to actually move much and we have plenty of food – maybe too much of it at times.”.

This means we’re not exposed to much hormetic stress on a day to day basis and we’ve lost the innate ability to know where the line is. However, really listening to your body is the best place to start. “It’s easy to really overdo it,” says Dr Kreindler. “To run too fast and bust your ligaments or go into super cold ice plunges when you’re not ready for it yet. The best thing is to build things up gradually and try to connect with how you really feel.”.