Which habits add the most years? Smoking, exercise, sleep — in years
Short answer: in large long-term studies, not smoking is linked to the biggest difference — about 10 years on average between lifelong smokers and people who never smoked. Regular physical activity comes next with a few years, followed by avoiding heavy drinking, a healthy weight, enough fruit and vegetables, regular sleep and less sitting.
The habits, roughly by size
- Smoking — about 10 years. The largest single factor in most studies. People who quit regain much of it, more the earlier they quit.
- Physical activity — a few years. Moving from inactive to around 150 minutes a week of moderate activity is linked to several extra years. Even 15 minutes a day counts.
- Heavy drinking — several years. The difference shows up at heavy intake; light drinking moves the number little.
- Health conditions — several years each. Diabetes, high blood pressure and heart disease each lower life expectancy, which is why they belong in any honest calculator.
- Weight — a few years at the extremes. The difference is largest for very high or very low BMI.
- Fruit and vegetables — about 1–2 years. Around 5 servings a day is linked to the lowest risk.
- Sleep and sitting — smaller. About 7–8 hours of sleep and fewer hours sitting are linked to lower risk; the size is modest.
What these numbers do and do not mean
- They are averages across groups, not a promise for one person.
- They come from observational studies, so part of the gap reflects other differences between the groups.
- They overlap, so you cannot just add them all up.
Where to start
Start with the biggest lever you actually have. If you smoke, that is usually it. If not, look at activity: a daily 30-minute walk is the easiest habit to keep. Then repeat small habits daily instead of planning a big change once.
How Spanlet helps
Spanlet's quiz shows each of your habits in years, so you see your own biggest lever. Tap a habit to try a different answer and watch the estimate change. The Today tab has 6 daily check-ins — a 30-minute walk, 7+ hours of sleep, 8 glasses of water, 5 servings of fruit and veg, a smoke-free day and an alcohol-free day — with the minutes you won back adding up as a motivating, symbolic number.
These numbers are population averages from published research, not a prediction for you. They are not medical advice — talk to a doctor about your health.
FAQ
Is it too late to quit smoking?
Studies of people who quit find they regain much of the lost life expectancy, and quitting earlier recovers more. Quitting at any age is linked to better outcomes.
How much exercise is linked to a longer life?
Even about 15 minutes of moderate activity a day has been linked to a few extra years compared with being inactive. Around 150 minutes a week is the common guideline.
Do the years from different habits add up?
Not fully. Habits overlap — people who exercise also tend to sleep and eat better — so good calculators cap each factor instead of simply adding every study's number.