↓ Jump to
- What Daily Habits Do Centenarians Have in Common?
- How Much Does Genetics Influence Living to 100?
- What Role Do Diet and Movement Play in Longevity?
- What Can Centenarian Studies Actually Prove?
- Frequently Asked Questions About Living to 100
Estimated reading time: 6 minutes
In a 2024 study involving 5,222 older adults in China, researchers found that people with the healthiest combination of smoking habits, exercise and dietary diversity had 61% higher odds of reaching 100 than those with the least favourable scores. (R) That doesn't mean you can guarantee a century of life. But it does suggest that the everyday choices you make may contribute to healthy ageing, even in your later decades. So, what can people who live to 100 teach you about longevity?
What Daily Habits Do Centenarians Have in Common?
You might imagine that reaching 100 requires an extraordinary lifestyle. Yet research suggests that some of the strongest associations with exceptional longevity involve surprisingly familiar habits.
In the 2024 Chinese longevity study, three behaviours stood out:
- Not smoking: Participants who had never smoked had higher odds of reaching 100 than current smokers.
- Staying physically active: Those who currently exercised were more likely to become centenarians than those who reported never exercising.
- Eating a varied diet: Greater dietary diversity was associated with higher odds of exceptional longevity. (R)
Interestingly, researchers did not find statistically significant associations between reaching 100 and either alcohol consumption or body mass index (BMI) in this particular study. (R) This challenges the idea that longevity can be explained by one dietary rule or body measurement.
Consistency May Matter More Than Perfection
Another study examining 878 centenarians in Chongqing, China, found that 92% were non-smokers and approximately two-thirds did not lead sedentary lifestyles. (R)
These findings suggest that you don't necessarily need an elaborate wellness routine. Instead, maintaining enjoyable, sustainable habits may be a more practical approach to supporting long-term wellbeing.
How Much Does Genetics Influence Living to 100?
Your genes contribute to longevity, but exactly how much remains an active area of scientific investigation. A landmark study involving 2,872 Danish twin pairs estimated the heritability of longevity at approximately 23–26%. (R) However, newer research suggests the relationship is more complicated.
Scientists use a measure called heritability to estimate how much variation in a characteristic, such as lifespan, is associated with genetic differences within a population.
A 2026 study published in Science estimated that genetic heritability of lifespan associated with intrinsic mortality may exceed 50% after accounting for external causes of death, including accidents and infections. (R) Importantly, this doesn't mean your genes determine half of your personal lifespan. Heritability describes variation across populations, not an individual's predetermined outcome.
Why Longevity Sometimes Runs in Families
Researchers studying more than 314,000 individuals across American and Dutch family datasets found that exceptional longevity clustered within families. People with exceptionally long-lived first- and second-degree relatives showed a survival advantage of up to 31% in the researchers' analyses. (R)
These findings support the importance of inherited biological characteristics. However, family history is only one part of your longevity picture. Your environment and everyday behaviours also deserve attention.
What Role Do Diet and Movement Play in Longevity?
Diet and movement are two of the most practical lifestyle factors you can influence. Research suggests that both are associated with exceptional longevity, although their biological effects extend beyond simply influencing lifespan.
Dietary Diversity Supports Nutritional Variety
A varied diet provides different combinations of protein, carbohydrates, fats, vitamins, minerals and dietary fibre. These nutrients contribute to processes including cellular energy production, muscle maintenance and normal metabolic function.
In the 2024 Chinese centenarian study, participants with higher dietary diversity scores had greater odds of reaching 100 than those with less varied diets. (R) However, the study did not establish that one specific food or dietary pattern was responsible.
For you, a practical approach is to enjoy variety across vegetables, fruit, legumes, wholegrains, nuts and other nutritious foods that suit your preferences and needs.
Everyday Movement May Be More Important Than You Think
You don't necessarily need to participate in organised sport to maintain an active lifestyle. A study of centenarians in Ourense, Spain, found that many participants had historically incorporated physical activity into everyday tasks, particularly agricultural work.
Remarkably, 90.3% reported not participating in sport, despite substantial levels of habitual physical activity. (R) This highlights an important distinction between structured exercise and daily movement. Walking, gardening and household activities can all contribute to an active routine.
Strength Training Supports Physical Function
Your skeletal muscles do much more than help you move. They also contribute to glucose metabolism, using circulating glucose to help meet the energy demands of muscular activity. In a randomised clinical trial involving older adults, a 12-week program combining resistance and aerobic exercise improved muscle strength, walking performance and several measures of physical function. (R)
These findings support incorporating appropriate strength-building activities alongside everyday movement. The most suitable activities will depend on your individual fitness, mobility and health circumstances.
What Can Centenarian Studies Actually Prove?
Centenarian research offers valuable clues about healthy ageing, but understanding its limitations is essential. Most studies examining people who reach 100 are observational. This means researchers measure characteristics and identify associations rather than randomly assigning participants to different lifelong behaviours.
For example, if centenarians report exercising regularly, researchers cannot automatically conclude that exercise caused their exceptional longevity. People who remain healthier may also find it easier to stay active.
Why Studying Exceptional Longevity Is Challenging
Researchers face several important challenges.
Survivorship bias occurs when a study focuses on people who have already survived to an exceptional age, potentially overlooking characteristics of those who did not.
Recall bias can arise when participants are asked to remember behaviours from decades earlier.
Researchers studying cognitively healthy Dutch centenarians specifically highlighted the difficulties of accurately reconstructing lifelong smoking, dietary and exercise habits. (R) There is also considerable variation between populations.
A lifestyle associated with longevity in one country may reflect cultural traditions, environmental conditions or other factors that differ elsewhere. That's why findings from centenarian studies are best interpreted alongside controlled clinical trials and broader population research.
Frequently Asked Questions About Living to 100
Do All Centenarians Follow the Same Diet?
No. Research has not identified one universal centenarian diet. However, greater dietary diversity was associated with higher odds of reaching 100 in a large Chinese study. (R)
Can You Improve Your Longevity Habits After 80?
Research suggests healthy habits remain relevant later in life. In a study of adults aged 80 and older, favourable lifestyle behaviours were associated with a greater likelihood of reaching 100. (R)
Is Living to 100 Mostly Genetic?
Not necessarily. Genetics contribute to lifespan, but heritability estimates vary depending on the population, methodology and causes of death considered. (R)
Do You Need Intense Exercise to Live Longer?
There is no evidence that intense exercise is essential for reaching 100. Observational research suggests that everyday physical activity is common among some centenarian populations, even without organised sport. (R)
One Last Thing
Perhaps the most encouraging lesson from centenarian research is that longevity isn't defined by one perfect habit. Your genetics provide part of the biological picture, while your everyday choices offer opportunities to support your health and vitality.
Rather than focusing exclusively on reaching a particular birthday, consider what helps you feel strong, connected and energised today. A nourishing meal, an enjoyable walk or a little more movement throughout your day can be a meaningful place to start.
Curious about how something as simple as walking can support healthy ageing? Explore our blog, Is Fast Walking Better Than Slow Walking?
