What stress really does to your body – and how to stop it making you sick

If stress dominates your life,  you’re not alone. In a global survey for World Mental Health Day in October 2023, 56 per cent of UK residents said they had felt so stressed in the past year it affected how they lived their lives, and 52 per cent had felt so stressed they felt they could not cope. The cost of living, world events and post-pandemic health worries have all had their impact. 

According to the Health and Safety Executive, stress is now one of the most common causes of long-term sick leave at work and, along with work-related anxiety and depression, accounted for in excess of 17 million working days lost in the UK in 2021/22, or 51 per cent of all cases of work-related illnesses in the UK in the same year. 

Therese Coffey, the former Environment Minister, has recently spoken out about the physical effects of stress, and said she “came close to dying” after developing a brain abscess following a period of extreme stress while working as a government minister. The Suffolk MP told the Sunday Times that she spent a month in hospital after she began to hallucinate and slur her words in May 2018.

“I just overdid it and burnt the candle at both ends,” she said. She says she now tries to “live in the moment” after resigning as Environment Secretary last month.

Why is stress increasingly a problem? “Studies show that over the last 30 years, self-reported stress is on the rise,” says Professor Neil Greenberg, a clinical and academic psychiatrist based at King’s College London. “Stress and anxiety have always been there but now people are more willing to talk about it.” Prof Greenberg served in the United Kingdom Armed Forces for more than 23 years as a psychiatrist and researcher, and is also managing director of March on Stress, a psychological health consultancy. 

He points to the rise of the internet, misinformation and social atomisation as reasons for growing stress levels. “I don’t think the world has become more stressful in itself, but today it has potentially more complexities to it and we are bombarded on lots of different fronts with information, and that can be difficult to cope with. Social cohesion helps protect against stress, so with more people working from home, social support and camaraderie can be lacking, which could also be causing stress to rise.”  

For Mandy Lehto, 52, an ex-director of sales at a German investment bank in London, the impact of stress had serious consequences. “I was always stressed. It was normal for me but then I found myself not being able to get to sleep,” she says. 

Living with her husband and her son and daughter, both under the age of five, life was busy. “I just drank industrial-strength coffee to keep me going”, she says, “but then I started to get heart palpitations and a rash on my face. It was vanity that eventually took me to the doctor”. She was diagnosed with stress and recommended antidepressants, but she refused to take them. She attempted to fix her symptoms by hiring a personal trainer, “but I passed out in my first boxing session”. 

“I thought I’d take a week off from the office and I’d be OK, but no amount of bed rest and kale smoothies could fix me. I felt tired all the time and just wasn’t strong enough to go into the office or even sort out the kids. I felt so low. For as long as I could remember, my value was all about being busy and now I could do nothing,” says Lehto. 

It took a year for her to regain her strength. She used nutrition, coaching and therapy to get to the bottom of what caused her to ignore her body’s signals. She decided to leave her job in the hope that she might feel better if she could go freelance and control her own schedule. She retrained as an executive coach and now hosts the podcast “Enough” where she discusses perfectionism, people-pleasing and overachieving, which Lehto says is at the root of many people’s stress. 

How does her life look now? “I got a dog, spend more time with the children and just take time to walk in the park every day.”

Why is stress harmful? 

“Large and small stressors can impact your health – anything from losing a loved one or losing your job to working all day in a stressful environment with high demands and low levels of control, as well as those little stressors of being late to a meeting or having a row with a friend”, says Daryl O’Connor, professor of psychology at the University of Leeds, who leads the Laboratory for Stress and Health Research (STARlab) where he works in the area of health psychology and psychobiology and investigates the impact of stress on the body. Although many people know that they are stressed, many don’t realise that stress is a quiet killer and that over time it can negatively impact your health and wellbeing, he says. 

What are the symptoms of stress?  

One of the problems with stress is that it can have many symptoms and be difficult to diagnose. “That’s why it’s essential that we all become what I call ‘stress aware’,” says Prof O’Connor. “There are lots of steps to leading a more stress-protected life and lots of easy ways to cope better with the stressors and strains of a hectic life. But firstly, you need to recognise that you are stressed.”

Research shows that stress affects nearly every bodily function. Your liver, for example, will produce extra blood sugar when you’re stressed, which then might increase your risk of developing Type 2 diabetes. Stress hormones can cause your heart to beat faster, which can increase your risk of high blood pressure and if it goes on for a prolonged period, can put you at risk of a stroke and heart attack.  

Stress also disrupts the way you digest food, with the potential to cause digestive issues and Irritable Bowel Syndrome. When you’re stressed you tense up, and over time this can cause headaches, back and shoulder pain, which in turn can lead to the avoidance of exercise, which also impacts your long-term health. In the short term, stress actually boosts immunity to help heal wounds as the body rushes to repair itself, but chronic, long-term stress weakens your immunity, which makes you more susceptible to viruses, including colds and flu. 

In the bedroom, stress hormones can cause loss of desire for both genders plus erectile dysfunction in men. It can cause disrupted and painful periods in women and can amplify symptoms of the menopause, including hot flushes, sleep problems, digestive issues, mood swings and weight gain. When you’re stressed, your body releases chemicals that can cause inflammation and make your skin even more sensitive, so you are also more likely to be affected by skin conditions such as eczema or psoriasis. “The cumulative science linking stress to negative health outcomes is vast,” says Prof O’Connor.

How to recognise symptoms of stress

Symptoms of stress fall into four categories, says Prof O’Connor. The first is anything that could be classed as “cognitive”, such as memory relapse, poor concentration, repetitive thinking and insomnia. The second is “emotional”, which includes irritability, tearfulness, low motivation, lack of confidence and self-esteem. Thirdly, look out for physical signs, which might include chest pains, colds and infections, panic attacks, high blood pressure, fast heart rate, digestive issues, headaches, back ache, skin problems, and weight loss or gain. 

Finally, look out for behavioural signs – you might find yourself not being able to relax or enjoy pleasurable activities and increasing negative behaviours such as caffeine, smoking, drinking and unhealthy eating. You might notice that socially you become more withdrawn or aggressive and you lack emotional stability so you’ll have emotional outbursts. “Once you recognise the symptoms, you can start adopting stress management approaches,” he says. 

The physical effects of stress on the body  

Stress affects the body by releasing hormones such as cortisol and adrenaline, which may damage your health if they’re released over long periods of time. They disrupt basic processes throughout your body and increase your risk of health problems, including heart disease, stroke and diabetes. Chronic stress is also known to contribute to depression and anxiety. But stress can also impact you by changing or disrupting your “habitual health behaviours” such as eating a balanced diet, getting exercise and sleeping well. 

“Stress has been shown to impact on weight gain by influencing changes in eating behaviour. Many adults and children are prone to eating more unhealthy, high-fat snack foods on days when they feel stressed, known as ‘stress-induced eating’. If these changes are maintained over time, they’re bad for your weight and your health,” says Prof O’Connor. 

What are the complications of long-term stress?

Most people can deal with short-term stress but if it’s chronic and prolonged, it means the stress response stays switched on, which causes “allostatic load”, the erosion caused to the body when your stress responses are all flashing on red for far too long. High allostatic load is associated with an increased mortality risk of 22 per cent for all-cause mortality and 31 per cent for cardiovascular disease mortality.

“This will lead to excessive wear and tear of virtually every biological system that we have, and to be blunt, it means your stress response mechanism is broken,” says Prof O’Connor. When this basic stress response is compromised, it could lead to increased vulnerability to depression, anxiety, suicidal feelings and post-traumatic stress disorder, as well as high levels of heart disease and dangerously high blood pressure.  

It can also get you stuck in a “learned helplessness” cycle, says Prof Greenberg, which is when a person does not use or learn adaptive responses to difficult situations. “People in this state typically accept that bad things will happen and that they have little control over them. They become unsuccessful in resolving issues even when there is a potential solution,” he says. This might lead to depression, or using substances or alcohol to help you sleep, which can lead to mental health problems. 

Long-term chronic stress can lead to blood pressure problems and all sorts of other issues, from your teeth (bleeding gums caused by stress suppressing the immune system) and your bowels (loose stools due to the inflammatory effect of stress) to your skin (acne flare-ups and psoriasis as the stress hormone cortisol boosts oil production). “Do not ignore the messages your body is giving you,” says Prof Greenberg. 

How can I prevent damage from stress? 

“We build our resilience by facing challenges and overcoming them. It’s important to get the balance right and to challenge yourself progressively, rather than throwing yourself in at the deep end,” says Prof Greenberg. But it’s also not about avoiding difficult situations. We should be trying to reduce the stressors where we can, but where we can’t, we should have a toolbox to help deal with them, he says. 

“In the first instance, you need to help yourself as much as you can. You have to be your own best friend. If you’re checking your emails 24/7, turn off your phone and email at 6pm and find ways to relax in the evening,” he says. “Get a good night’s sleep, lay off the alcohol and spend a Sunday with your family.” 

Beware all-or-nothing thinking. “Sometimes when we’re very stressed, we think, ‘Oh well, I’m going to throw this all in, I can’t do it.’ But take some time out to relax and you will get to a better place.” If this approach doesn’t work, he advises you to reach out either to a trusted friend, your GP or even someone like a priest, if you are religious. “Talk to anyone where you feel you can have an honest conversation,” he says. 

In the workplace, it’s important to be aware of how you’re feeling as this is an environment where you are more at risk of ongoing chronic stress. Prof Greenberg has conducted studies about the efficacy of “psychologically savvy conversations” at work. “Buddy up with a colleague and if you’re working in a high-stress situation, check in with them every hour. I call it a ‘check-up from the neck up’, especially if something difficult has happened. The evidence shows that if your managers and the team are trained to check in after challenging events, it can lead to a 90 per cent reduction in mental health symptoms or sickness,” he says. Prof Greenberg defines a high-stress situation as working long hours in high-pressured environments and exposure to traumatic situations and moral dilemmas. 

He also recommends physical exercise. “Whether you’re walking, running or weightlifting, you aren’t on a keyboard so you’re giving yourself a break from work, as well as the obvious health benefits of exercising,” he says.

Exercise reduces levels of the body’s stress hormones, such as adrenaline and cortisol, and also stimulates the production of endorphins, chemicals in the brain that are the body’s natural painkillers and mood elevators. Endorphins are responsible for the “runner’s high” and the feelings of relaxation and optimism after a workout. 

Prof Greenberg also recommends connecting with people who matter. “The latest research shows that when you’re nice and give to others, it’s a huge stress reliever. Combine this with one hour of immersing yourself in nature every week – a walk in a forest, a sea swim, and you have a scientifically proven toolbox to protect against stress,” he says. 

Cognitive behavioural therapy is useful, says O’Connor, as it helps you identify, challenge and change maladaptive thought patterns in order to alter their responses to difficult situations that may be making a stressful situation worse. He’s also a fan of acceptance and commitment therapy (ACT), which encourages you to accept what you can’t change while focusing on changing things that are within your control.