Every year spent in education adds an average of 11 months to people’s lives, DNA scientists say.
The researchers say a person loses two months for each kilogram of overweight. And seven years for smoking a pack of cigarettes a day. Unusually, the University of Edinburgh team found their answers by analyzing the differences in the genetic code of humans or DNA. In the end, they think that they will discover new ways to help us live longer.
The group used the genetic code of more than 600,000 people participating in a natural but massive experiment.
Closer picture If someone smokes, drinks, gives up school and has overweight, it may be difficult to identify the impact of certain unhealthy behaviors.
Instead, the researchers turned to the natural experiment. Some people carry mutations in their DNA that increase appetite or make them more likely to increase weight, so researchers could compare those programmed to eat more with those who were not – no matter what their wider way of life.
Dr. Peter Joshi, of the University of Usher Institute, said: “It’s not confusing with the analysis. You can directly look at the effect of weight, isolated, on the lifespan.” Similar groups of mutations are related to how long people spend in education and enjoyment they receive from smoking or drinking.
The research team also found specific mutations in human life-changing DNA, published in the Nature Communications journal. Mutations in a single gene (a set of instructions in DNA) involved in the management of the immune system can add seven months of life. People with a mutation that increased levels of bad cholesterol lasted eight months of life expectancy.
A rare mutation in the genome – APOE – related to dementia reduces lives in 11 months. And those who made smoking more appealing reduced their lives by five months
Dr Joshi says these genetic variants are “the tip of the iceberg”. He says that about 20% of lifestyle variations can be inherited, but only 1% of such mutations have not yet been found. However, he said that while genetics affects life expectancy, “you have an even greater impact” through the choices you make.
Dr Joshi told the BBC: “We hope to discover new genes that affect life expectancy to give us new aging information and build therapeutic aging interventions. ” There are also some mutations of diseases that clearly affect life expectancy and a devastating effect, such as Huntington’s genes. People with Huntington often die in their 20s.
However, to follow people until the end of their lives, much of the study of humans was before 1940.
Professor David Melzer, from the Medical School at Exeter University, said: “The additional year of education then may be more important than it is now.”