- Telomeres function as protective “ends” on our chromosomes.
- Shortened telomeres are associated with a higher risk of lifestyle‑related diseases.
- Although our genes partly determine telomere length, an increasing number of studies show that it is also strongly influenced by lifestyle.
What are telomeres?
You can think of telomeres as small “protective caps” at the ends of our chromosomes – the structures that hold our genetic information in every cell.
Telomeres and ageing: Why do they shorten, and what does it mean?
Every time a cell divides, its DNA is copied, but the process isn’t perfect. A tiny portion of the telomeres is “lost” each time.
When telomeres become too short, the cell can no longer divide and effectively goes into “retirement” – a process known as cellular senescence – or it may die altogether (apoptosis). This is a natural mechanism that protects the body from damage and, for example, from the development of cancer. However, it also means that the shorter our telomeres are, the older our tissues become and the less able they are to regenerate.
It isn’t just repeated cell division that shortens telomeres. Research shows that stress plays a significant role – particularly oxidative stress and inflammatory processes. Oxidative stress can arise from smoking, an unhealthy diet, chronic stress or lack of sleep. Free radicals circulate in the body and can damage telomeres, which are especially sensitive to this kind of attack.
Put simply: telomeres are not only a countdown of cellular age but also a reflection of our lifestyle. A poor internal environment – whether due to stress, inadequate nutrition or low‑grade inflammation – can speed up telomere shortening and, with it, the ageing process.
Although the body does have an enzyme called telomerase, which can repair telomeres, its activity is very low in most normal (somatic) cells. Exceptions include stem cells and germ cells. This means that our everyday cells can do very little to counteract telomere shortening, so it’s up to us to help protect them through healthy lifestyle choices.
How does lifestyle affect telomere shortening?
Although telomeres naturally shorten with age, research shows that the rate of this shortening can be influenced to some extent by how we live. Various lifestyle factors – diet, exercise, stress, smoking, sleep – all contribute to whether our cells age faster or slower. Here’s an overview of what we know from current research.
Diet
Most research to date has focused on the relationship between diet and telomere length.
What supports healthy telomeres?
- A Mediterranean diet rich in vegetables, fruit, fish, olive oil and wholegrain products has been associated with longer telomeres in many observational studies. The same applies to diets higher in polyphenols (found in cocoa, berries, green tea and olives).
- Fibre, omega‑3 fatty acids and antioxidants can help reduce oxidative stress and may therefore slow telomere shortening.
What harms telomeres?
Diets high in ultra‑processed foods, sugary drinks and red or processed meat have been associated with shorter telomeres in multiple study populations.
What do intervention studies say?
- A recent randomised clinical study (2025) followed 164 overweight adults who undertook a four‑month weight‑loss diet. Women who consumed more protein (around 30% of daily energy intake) had longer telomeres at the end of the study, while women on a low‑fat diet showed telomere shortening. In men, the differences were not statistically significant.
- Another intervention study found that a diet with lower inflammatory potential (within a Mediterranean dietary pattern) helped slow telomere shortening.
Exercise
Physical activity is another strong factor influencing cellular aging:
- People who exercise regularly (walking, running, swimming, strength training) tend to have longer telomeres than those with sedentary lifestyles.
- Regular activity likely acts through several mechanisms: it reduces oxidative stress, lowers inflammation, improves metabolic health and boosts endorphin production – which can also help counter stress. For example, regular exercise supports the prevention of depression, and depression has been linked to telomere shortening.
Smaller intervention studies also suggest that even a few weeks of regular exercise can increase telomerase activity – the enzyme responsible for lengthening telomeres. However, measurable changes in telomere length are usually seen only with long‑term lifestyle habits.
Stress
Chronic psychological stress – for example, long‑term strain, caring for a sick family member, or job burnout – has been linked in studies to shorter telomeres, sometimes even in young people.
- Persistently elevated cortisol, disrupted sleep rhythms and oxidative stress are thought to contribute to faster telomere shortening.
- On the other hand, techniques such as mindfulness, relaxation and psychotherapy can help to offset some of this negative impact.
Smoking and alcohol
Smoking is among the most harmful lifestyle factors for telomere health – smokers’ telomeres are often shortened by several years compared with non‑smokers.
Excessive alcohol consumption is also associated with risk, although moderate drinking has not yet been clearly linked to shorter telomeres.
Sleep
Although research exploring the relationship between sleep and telomere length is still emerging, several studies suggest that chronic sleep deprivation and irregular routines may increase oxidative stress, which can contribute to telomere shortening.
- Learn more: 9 Tips on How to Improve Sleep Quality
Obesity
Body weight – specifically, excessive fat mass – is another important factor influencing telomere length due to its pro‑inflammatory effects.
Studies show that a higher BMI, waist circumference andgreater body fat are associated with shorter telomeres. This relationship has been observed across age groups and genders, even after adjusting for other lifestyle factors.
Possible mechanism: Obesity increases oxidative stress and promotes chronic inflammation – two processes directly linked to telomere shortening. Fat tissue also produces inflammatory cytokines (such as TNF-α and IL‑6), which can accelerate cellular ageing.
Note: Most intervention studies in this field lasted only a few months. Because changes in telomere length occur slowly, this may underestimate their true impact. Conversely, observational studies – even when long‑term – cannot fully rule out other influencing factors such as socioeconomic status or genetic predispositions.
How to slow telomere shortening, or even lengthen them?
Telomere shortening is a natural part of ageing, but it doesn’t need to happen faster than necessary. Current scientific evidence shows that a healthy lifestyle can help slow cellular ageing and protect telomere length. The following recommendations are based on findings from observational studies, systematic reviews, and several intervention trials.
1. Eat a balanced diet rich in plant foods
- Include plenty of vegetables, fruit, legumes, whole grain products and nuts.
- Prioritise a Mediterranean‑style diet, which has been shown to reduce low‑grade inflammation – a contributor to accelerated telomere shortening.
- Focus on foods rich in polyphenols – antioxidants found in blueberries, green tea, dark chocolate, olive oil and coffee.
- Make sure you’re getting enough fibre, vitamins C, E and D and omega‑3 fatty acids, all of which support telomere stability and help reduce oxidative stress.
Strength of evidence: Moderate (supported by observational studies and some intervention research, such as Mediterranean diet trials).
2. Consider a higher protein intake when losing weight
- If you’re trying to lose weight, a slightly higher protein intake (around 30% of daily energy) may not only support weight reduction in women but also help slow telomere loss.
- This is based on the only available study to date that showed telomere lengthening in obese women following a higher‑protein diet compared with a low‑fat diet.
Strength of evidence: Moderate to strong (randomised controlled trial, though short‑term and limited to women undergoing weight loss).
3. Exercise regularly
- Combine aerobic activity (brisk walking, running, swimming) with strength training.
- Ideally, aim for at least 150 minutes of moderate‑intensity exercise per week, or 75 minutes of high‑intensity activity.
- Even short‑term increases in physical activity can elevate telomerase activity – the enzyme that helps lengthen telomeres – while long‑term exercise habits are consistently associated with longer telomeres.
Strength of evidence: Moderate (positive effects observed in both observational studies and smaller intervention trials).
4. Maintain a healthy body weight
- A higher body fat percentage, waist circumference, and BMI are all associated with faster telomere shortening.
- Obesity promotes chronic inflammation and oxidative stress, both of which damage telomeres.
- Weight reduction – particularly when accompanied by improved metabolic health – can help protect telomeres.
Strength of evidence: High (supported by consistent findings from multiple studies, including RCTs).
5. Manage chronic stress
- Chronic stress, anxiety, and traumatic experiences can accelerate telomere loss and may also affect telomerase activity.
- Techniques such as relaxation and breathing exercises, psychotherapy and mindfulness can help.
- The quality of your relationships and the level of perceived social support also play an important role.
Strength of evidence: Moderate (well documented in longitudinal studies, though intervention research remains limited).
6. Don't smoke and limit alcohol intake
- Smoking significantly shortens telomeres – with an impact equivalent to several years of additional biological ageing.
- The evidence on alcohol is less clear: moderate consumption has not been consistently linked to telomere shortening, but chronic heavy drinking has been associated with negative effects.
Strength of evidence: High (especially strong for smoking).
7. Ensure sufficient, good‑quality sleep
- Aim for 7–9 hours of sleep per night, ideally following a consistent routine.
- Sleep deprivation disrupts hormonal balance, increases oxidative stress, and may contribute to telomere shortening.
Strength of evidence: Low to moderate (limited number of studies, though the biological mechanisms are well understood).
Bottom line
Telomeres are the protective ends of our chromosomes and act as biological clocks for cellular ageing. Their shortening is a natural process, but lifestyle greatly influenceshow quickly it happens. Scientific evidence shows that longer telomeres are associated with a healthy body weight, a nutritious diet rich in fibre, antioxidants and polyphenols (e.g., in the Mediterranean diet), regular exercise and the ability to manage stress. On the other hand, obesity, a sedentary lifestyle, smoking, chronic stress and poor sleep are associated with faster telomere shortening – and therefore accelerated biological ageing.
From a practical standpoint, it’s not about a single “miracle” intervention, but rather a combination of long‑term habits that create a healthier internal environment for your cells. Changes may not be obvious straight away – telomeres themselves respond slowly – but they do respond. Taking care of your diet, exercise, sleep, and mental health, while reducing risk factors such as smoking, not only improves day‑to‑day well‑being but also has a meaningful impact on your long‑term health and longevity.
