The guide

What adds the most years? The 20 habits, ranked

By GyroscopeUpdated November 15, 202625 sources

In order of size, don’t smoke. Get fit. Get strong. Know your blood pressure and bring it down if it’s high. Keep a steady wake time. Then eat mostly whole foods, shrink a big waist and drink less if you drink a lot. In a study of 123,219 US adults, five of these habits at 50 meant 12 to 14 more years.

Ask how to live longer and you get a list of 30 things, all said with the same weight, from supplements and cold showers to blueberries, 10,000 steps and eight glasses of water. The studies say a few things are much bigger than everything else, and it pays to do those first.

Why is there an order?

Because the sizes are so different. In the Harvard study, smoking 15 to 24 cigarettes a day went with 2.33 times the death rate of never smoking, and doing no exercise went with twice the death rate of 3.5 to 6 hours a week. A BMI of 25 to 30 carried only about 5% more risk than 23 to 25. All three get talked about as “healthy habits”, and the first is far bigger than the last.

A picture from daily life

If your boat has three leaks, you plug the biggest one first. Bailing harder doesn’t help much while water pours in through the hull. For a smoker, smoking is the big hole. For most other people, it’s sitting still.

Our ranking

Twenty habits, in three groups. The first three carry most of the years, the next five are big for many people, and the last twelve are smaller or narrower. Within a group, the order is rough, since each number comes from its own study.

The big three

1. Don’t smoke, or quit. In 202,248 US adults, smokers died at about three times the rate of people who’d never smoked and lost more than 10 years of life. Of women aged 25, 70% of never smokers reached 79, against 38% of smokers. People who quit at 25 to 34 gained about 10 years over those who kept going, at 35 to 44 about 9 and at 45 to 54 about 6. British doctors who quit at 60 still gained about 3. What quitting gives back.
2. Get fit. In the Harvard study, even under an hour a week of moderate or vigorous activity went with a 35% lower death rate than none, 3.5 to 6 hours a week with half the death rate, and 6 hours or more with 56% lower. In 122,007 people who ran a treadmill test, being below average for fitness carried the same extra risk as smoking (1.41 times the death rate of above average), and the least fit quarter died at about 5 times the rate of the fittest 2 percent. The benefit kept rising even at the very top. The US guideline is at least 150 to 300 minutes a week of moderate activity such as brisk walking. A typical goal is 30 to 50 minutes a day, and the Gyroscope app personalizes yours. vo2max.guide covers how to raise your fitness number.
3. Get strong. In 147,374 US health professionals followed for up to 30 years, 90 to 119 minutes a week of strength training went with a 13% lower death rate, on top of whatever aerobic exercise they did. There was no extra benefit past 2 hours a week. The lowest risk of all was in people who did plenty of both. The US guideline is strength work at least two days a week. Is cardio all you need?

The next five

4. Know your blood pressure. Nearly half of US adults (48.1%) have high blood pressure, and only 22.5% of them have it under control. At 40 to 69, each 20 points (mmHg) higher systolic (the top number) went with more than twice the death rate from stroke and twice the rate from coronary heart disease. A week of home readings tells you where you stand. bloodpressure.guide has how to lower it.
5. Keep a steady wake time. In 60,977 UK adults who wore activity trackers, the more regular sleepers had a 20 to 48% lower death rate than the least regular fifth, and regularity predicted death better than hours slept. Getting up at the same time every day, weekends included, is the simplest way in. Is eight hours what counts?
6. Eat mostly whole foods. In the Harvard study, people in the top fifth of a healthy eating score had a 37% lower death rate than the bottom fifth. We’d fill the plate with vegetables, fruit, beans, nuts, whole grains and fish, with little processed meat or soda. What is the best diet for a long life?
7. Shrink a big waist. A BMI of 30 to 35 carried 25% more risk than 23 to 25, and 35 and over 67% more. Under 30, the extra risk was small. bodyfat.guide has everything you need to know about fat loss.
8. Drink less, if you drink a lot. 30 g of alcohol a day or more, a bit over two US drinks (14 g each), carried 25% more risk than 5 to 15 g. Light drinking doesn’t add years once former drinkers are counted separately, so if you don’t drink, don’t start. Does drinking shorten your life?

Whole foods, a smaller waist and less drink each add about 2 to 4 years at 50 in our calculator.

Twelve smaller ones

Each of these was tied to fewer deaths in large studies, by less than the eight above or in fewer people. Several are the small, everyday version of a bigger habit, and ten small changes turns the easiest into a plan for this week.

How many years does each one add?

These are our calculator’s figures for a 50 year old who has the other habits in place. Each is worked out from the Harvard study’s death rates applied to the 2024 US life table, one habit at a time.

The calculator always puts quitting first for a smoker. For someone of 50 who smokes and doesn’t exercise, the math puts moving a touch above quitting, but the sooner someone quits the more it gives back, so it leads. Strength, blood pressure and sleep aren’t in the estimate because the Harvard habits study didn’t measure them, which is why the quiz asks about them separately.

Why can’t you add them up?

Because people who do one of these tend to do others, and each number comes from a study that already allowed for some of the rest. In the Harvard study the five habits together, at 50, came to about 14 extra years for women and 12 for men. Add up the single figures above and you get more than that, which can’t be right. Our calculator works out each missing habit on its own and shows them side by side, never summed.

The British doctors

In 1951, researchers asked 34,439 male British doctors about their smoking and then followed them for 50 years. Men born from 1900 to 1930 who kept smoking cigarettes died about 10 years younger than lifelong non-smokers. Those who stopped at 30 gained back about 10 years, at 40 about 9, at 50 about 6 and at 60 about 3. Stopping at 50 halved the extra risk, and stopping at 30 avoided almost all of it.

Don’t healthy people just do healthy things?

If you have heart disease, chest pain when you exert yourself, or haven’t exercised in years, start with walking and check with your doctor before hard training.

What isn’t on the list?

No pill, supplement or DNA test is on it, because none has been shown to add years to a healthy person. Do longevity pills add years?

Your turn

See your own estimate, and the habit costing you the most years, or take the two-minute quiz for your biggest change and the next two.