An emergency programme from the Stone Age
Imagine you are living many thousands of years ago. You are gathering berries at the edge of the forest when something rustles in the bushes. A sabre-toothed tiger. In a split second, your body takes command: your heart races, your muscles tense, sugar floods into your blood, your senses are wide awake. You run as fast as you can and reach the safety of your cave. After a few minutes your breathing settles, your heart slows down and your body powers down again.
Today, you no longer meet sabre-toothed tigers. Instead, your phone rings during dinner, 40 unread emails are waiting in your inbox and the deadline is getting closer. Your body responds with the same ancient programme. Only you cannot run away from a full inbox, and unlike the tiger, it does not disappear after a few minutes. So for many people the alarm simply stays on: in the morning, at midday and often still at night in bed.
Of course, this is simplified. But at its core it is true, and this is exactly where the link to biological age begins. Your chronological age counts the years since you were born. Your biological age describes the actual condition of your body, for example how well your cells renew themselves and how elastic your blood vessels are. An alarm that never fully switches off puts a strain on both. But what exactly happens in your body?
What chronic stress does to your body
At the centre of the stress response is a hormone called cortisol. In acute moments it is a real help: it provides energy, sharpens attention and briefly puts the brakes on inflammation. It only becomes a problem when levels stay high for weeks and months.
Picture a car standing at a traffic light while someone keeps pressing the accelerator. The car does not move an inch, but the engine is revving in the red zone and wearing out. Your body goes through something similar under chronic stress. Blood pressure stays raised and puts pressure on the blood vessels. Blood sugar keeps spiking. And over time, immune cells respond less and less to the cortisol that is supposed to slow them down. The result is a quiet, persistent inflammation that you cannot feel but that is considered one of the drivers of biological ageing.
The telomeres, the protective caps at the ends of your chromosomes, do not seem to be unaffected either. With every cell division they get a little shorter. Once they are too short, the cell stops working and sends out inflammatory signals. Their length is therefore considered one of the markers of how far your body has already aged biologically. You can find out more about telomeres here (Article: Biological age). In a widely noted study, psychologist Elissa Epel examined 58 mothers, many of whom were caring for a chronically ill child. The women who felt most stressed had telomeres so short it was as if their cells had aged at least a decade faster. Larger analyses show that the link is smaller on average than this study suggests. But one detail stood out: what mattered most was how burdened the women felt.
Does that mean you should avoid stress at all costs?
Why stress is not the problem, but the missing break
No. Short-term stress is part of life, and it can even do you good. A presentation, a competition, a difficult conversation: the body ramps up, masters the situation and then powers down again. Much like with training, it becomes more resilient over time.
Things get difficult when that second half is missing. When one strain is followed directly by the next, your thoughts keep circling in the evening and even the weekend is no longer enough to catch your breath. Then the body stays in a state of alarm that was really only meant to last minutes.
Added to this is what the study with the mothers hints at: how you experience a situation makes a difference. Someone who feels at the mercy of a burden reacts differently from someone who sees it as a solvable task. And anyone who knows good ways to wind down again cushions a large part of the impact. There is a lot to suggest that even frequent stress weighs much less heavily if it is regularly followed by recovery.
For your biological age, what counts is less how much stress you experience than how often you come back to rest afterwards.
But how do you manage that when your mind simply refuses to switch off? A small study from California offers a remarkable clue.
Twelve minutes a day: What meditation changes in your cells
Psychiatrist Helen Lavretsky of the University of California, Los Angeles turned to a group under particularly heavy chronic stress: people caring for a relative with dementia. Almost 50 of them, aged between 45 and 91, took part in her study.
Half of them learned a short meditation from yoga, in which you quietly repeat syllables while making simple finger movements. The other half listened to relaxing music, also in a quiet setting with their eyes closed. Both groups set aside twelve minutes for this every day for eight weeks.
Afterwards, both groups felt better, which is hardly surprising with a daily break. Things got interesting when the researchers looked at their blood. In the meditation group, telomerase activity had risen by 43 percent. This enzyme can maintain the telomeres and partly even lengthen them again, the very protective caps that wear out faster under chronic stress. In the music group, the increase was just under four percent. Low mood also eased considerably more often among those who meditated.
It was a small study, and a single result does not prove much on its own. But larger analyses of many studies point in the same direction: regular meditation can lower the stress hormone cortisol, blood pressure and inflammation markers in the blood. In other words, exactly the values that get out of balance under chronic stress.
Twelve minutes a day is not much time. For your body, it can still make a measurable difference.
Meditation is not the only way, though. Sometimes it is enough just to step outside.
Out into the green: Why nature turns the alarm down
Researchers at the University of Michigan asked city dwellers to take a nature break at least three times a week for eight weeks: time spent somewhere that felt like nature to them, whether a park, a garden or a woodland path. They were free to choose when and where. Before and after the breaks, they gave saliva samples in which cortisol was measured.
Just 20 minutes in green surroundings measurably lowered the stress hormone. The effect was strongest at 20 to 30 minutes; after that it grew only slowly. One possible explanation: rustling leaves, birdsong and open views hold your attention in a gentle way. Your mind is allowed to wander instead of constantly having to react.
This seems to pay off in the long run too. In a study from England with almost 20,000 people, those who spent at least two hours a week in nature felt healthy and satisfied considerably more often. It made no difference whether those two hours came in one stretch or added up over several short outings. And large population studies show that people with more greenery around them live slightly longer on average.
How can you fit all of this into a busy everyday life?
How much relaxation do you need?
Unlike for exercise, there is no official recommendation for relaxation. But the studies provide good guidance: ten to twenty minutes of meditation a day, half an hour in the park on several days a week, or around two hours in green spaces per week in total. That fits into almost any routine.
More important than the method is that it suits you. Some people find calm in a guided meditation, others on a walk without their phone, while gardening or in a few slow, deep breaths between two appointments. Exercise also helps the body wind down after a period of strain. Read more here (Article: Endurance). As a rule of thumb: whatever makes your breathing calmer and your thoughts slower is good.
Why small breaks do more than a long holiday
Many people hope to make up for everything on holiday. However, the recovery often wears off within just a few weeks. Your body does not need to return to rest once a year, but again and again, ideally every day.
A single break on its own changes little. Once it becomes a habit, your body keeps getting the chance to switch off the alarm before it becomes a permanent state.
You do not have to turn your life upside down for this. It is enough not to leave recovery to chance, but to give it a fixed place in your day.
Where the BioAge test helps and where it doesn't
The BioAge test also asks how stressed you feel and how often you deliberately take time to relax. It can be a nudge to take an honest look at how much room for rest there currently is in your everyday life. But it is no more than a first check-in. It can in no way replace an open and honest conversation with someone you trust or with a professional.
Frequently asked questions about stress, relaxation and biological age
How can I tell that stress is becoming too much?
Typical warning signs are sleep problems, tiredness that persists even after days off, irritability or physical complaints such as headaches or stomach aches. If they last for several weeks, it is worth talking to your GP.
Is there a quick exercise for acute tension?
Yes, and you always have it with you: your breath. Breathe in calmly through your nose and breathe out for longer, for example four seconds in and six seconds out. Just a few minutes of slow breathing help your body switch from alarm mode to rest mode.
How do I start meditating if I have never done it before?
Small. Five minutes in which you simply observe your breath are a good start. An app or a course can help you stick with it. Many German health insurers (Krankenkassen) subsidise certified stress management courses.
What helps if I can't switch off in the evening?
Many people find it helps to write down open tasks before going to bed. In one sleep study, participants fell asleep faster when they spent five minutes writing a to-do list for the next few days. Read more here (Article: Sleep).
Does a glass of wine help you relax?
In the short term, it often feels that way. But alcohol worsens the quality of your sleep and with it exactly the recovery your body needs after a stressful day.