Just five extra minutes of exercise and half an hour less sitting time each day could help millions of people live longer, according to research highlighting the potentially huge population benefits of making even tiny lifestyle changes.

Until now, evidence about reducing the number of premature deaths assumed that everyone must meet specific targets, overlooking the positives of even minor increases in physical activity.

Moderate-intensity physical activity such as brisk walking for an extra five minutes a day was associated with an estimated 10 per cent reduction in deaths, the study of 135,000 people from the UK, US, Norway and Sweden found.

Researchers led by the Norwegian School of Sport Sciences also found reducing sedentary time by 30 minutes a day was associated with an estimated 7 per cent reduction in all deaths.

The greatest benefit was seen if the least active 20 per cent of the population increased their activity by five minutes each day. The findings were published in the Lancet.

The authors stressed that while the findings should not be used as personal advice, such as specific exercise recommendations for individuals, they showed the potentially vast benefits for populations as a whole.

Prof Aiden Doherty, of the Nuffield Department of Population Health at the University of Oxford, who was not involved with the study, said the “excellent” analysis was “a leap forward” from existing evidence.

“While this might seem like yet another ‘more physical activity is good for you’ study, the authors have added important new details,” Doherty said.

“This paper indicates that up to 10 per cent of all premature deaths might be prevented if everyone were to make small and realistic increases to their moderate-intensity physical activity of five minutes a day. Reducing sedentary time by 30 minutes a day would likely result in a smaller, but still meaningful, number of averted deaths.”

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Daniel Bailey, a reader in sedentary behaviour and health at Brunel University of London, who was not involved in the study, said the “really promising” finding was that just five more minutes a day of moderate-intensity physical activity could save lives. “This should be feasible for most people, even those who only do very small amounts of physical activity already,” Bailey said.

“Moderate activities are those what make us breathe a bit heavier and feel warmer. So simple daily activities like a brisk walk, housework or gardening will do the trick. And if we want to reduce sitting by 30 minutes a day, this can be swapped for light activities like pottering around the house or a slow walk.”

Meanwhile, a second study, published in the eClinicalMedicine journal, found that when combined, small improvements in sleep, physical activity, and diet were linked with a longer life.

For example, an extra five minutes of sleep, two minutes of moderate to vigorous physical activity – such as brisk walking or taking the stairs – and an additional half a serving of vegetables a day could lead to an extra year of life for those with the worst sleep, physical activity, and dietary habits.

Experts led by the University of Sydney gathered information on the levels of activity, diet and sleep of almost 60,000 people taking part in the UK Biobank study.

Compared with people with the worst sleep, physical activity and dietary habits, the study suggested that the optimal combination of these behaviours – seven to eight hours of sleep per day, more than 40 minutes of moderate to vigorous physical activity a day and a healthy diet – was associated with living almost a decade longer. – Guardian