Weight loss, education, giving up smoking, and being open to new experiences have all been linked to longer life.
By combining genetic, lifestyle and family data from 600,000 people, researchers have been able to calculate the effect of specific factors on life expectancy.
'You can look directly at the effect of weight, in isolation, on lifespan,' explained author Dr Peter Joshi of the University of Edinburgh's Usher Institute.
Certain lifestyle choices, such as smoking, are known to affect health and life expectancy. Furthermore, certain genes are known to affect lifestyle behaviours and choices - such as a mutation linked to feelings of increased appetite. By comparing people who have such known mutations to those who do not, researchers at the University of Edinburgh were able to investigate the impact of genetic traits which affect lifestyle and disease on overall lifespan.
The researchers used data from 25 separate population studies from Europe, including the UK BioBank, and from Australia and North America. They combined the participants’ genetic data with records of their parents’ lifespan. As each participant shares half their genetic information with each of their parents, they could assess the impact of different gene variants on life expectancy.
Their findings suggested every year spent in education could add an average of 11 months to people’s lifespan, and openness to new experience also increased life expectancy.
For every kilogram that a person was overweight, their lifespan was decreased by two months. The researchers also discovered a mutation that made smoking more appealing could cut lives by five months.
The researchers also discovered two new gene variants which affected lifespan, including one which increased levels of bad cholesterol in the blood and reduced lifespan by around eight months. The other, in a gene linked to the immune system, added around half a year to life expectancy.
‘We hope to discover novel genes affecting lifespan to give us new information about ageing and construct therapeutic interventions for ageing,’ said Dr Joshi to the BBC, saying that 20 percent of variation in lifespans may be inherited, but only one percent of such mutations have been found so far.
‘This is a large and important study, which confirms a lot of recent work in this area,’ said Professor David Melzer of University of Exeter Medical School, who was not involved in the study. He cautioned however that the analysis was mainly based on the lifespans of parents of middle-aged volunteers who took part in UK Biobank from 2006 to 2010.
‘Therefore the estimates of effect may not be relevant to our population now: an extra year of education then may have been much more important than it is now,' he said, also pointing out that people would not have had modern treatments for conditions such as high cholesterol.
The study was published in Nature Communications.