“Improvements in medical technology are often thought to be the gatekeeper to healthier, longer life,” said lead author Mikko Myrskylä, director of the Max Planck Institute for Demographic Research in Germany.
“We showed that a healthy lifestyle, which costs nothing, is enough to enable individuals to enjoy a very long and healthy life.”
The study, conducted by Myrskylä and Neil Mehta, Professor of Health Management and Policy at the University of Michigan, USA, analysed data for more than 14,000 individuals and found that people who had never smoked and were not obese lived between four and five years longer than the general population. These extra years were free of disability.
Additionally, individuals who also consumed alcohol moderately lived seven more disability-free years than the general population, and had a total life expectancy surpassing that of the population of Japan.
Myrskylä said: “A moderately healthy lifestyle is enough to get the benefits. Avoiding becoming obese, not smoking and consuming alcohol moderately is not an unrealistic goal.”
The researchers noted that each of the three unhealthy behaviours – obesity, smoking and unhealthy consumption of alcohol – was linked to a reduction in life expectancy and to an earlier occurrence of disabilities.
There was a big difference in average lifespan between the groups who were the most and the least at risk.
Men who were not overweight, had never smoked and drank moderately were found to live an average of 11 years longer than men who were overweight, had smoked and drank excessively.
For women, the gap between these two groups was found to be even greater, at 12 years.
Mikko Myrskylä said: “The most positive result is that the number of years that we have to live with physical limitations does not increase as we gain more years through healthy lifestyle.
“Instead, healthy lifestyle is associated with a strong increase in physically fit years. In other words, the years we gain through a healthy lifestyle are years in good health.
“Our results show how important it is to focus on prevention. Those who avoid risky health behaviours are achieving very long and healthy lives. Effective policy interventions targeting health behaviours could help larger fractions of the population to achieve the health benefits observed in this study.”