Health Desk—Oct 14, 2017: Every year spent in education adds an average of 11 months to people's lifespan, say scientists.
The researchers say a person loses two months for every kilogram overweight they are - and seven years for smoking a packet of cigarettes a day.
Unusually, the Edinburgh university team found their answers by analysing differences in people's genetic code or DNA.
Ultimately they think it will reveal new ways of helping us to live longer.
The group used the genetic code of more than 600,000 people who are taking part in a natural, yet massive, experiment.
If someone smokes, drinks, dropped out of school and is overweight, it can be difficult to identify the impact of one specific unhealthy behaviour.
Instead, the researchers turned to the natural experiment.
Some people carry mutations in their DNA that increase appetite or make them more likely to put on weight, so researchers were able to compare those programmed to eat more with those who were not - irrespective of their wider lifestyles.
Courtesy: BBC News