A large-scale study of human genetics confirms that a healthy lifestyle can extend life

Even though genetics may put some of us at greater risk of early death, a healthy lifestyle could help significantly reduce our risk of death, according to a new study. A healthy lifestyle can compensate for the impact of genetics by more than 60% and can add another five years to life, according to the first study of its kind, reports News.ro.

The research found that although genetics may mean a 21% higher risk of early death, people can improve their chances of living longer.

That risk could be mitigated by about 62 percent in people with a genetic predisposition, said lead author Dr. Xue Li, dean of the School of Public Health at Zhejian University School of Medicine in China.

Many studies have shown the link between a healthy lifestyle and longevity, and others have emphasized the genetic component in lifespan, but the report, published Monday in the journal BMJ Evidence-Based Medicine, explored how the two correlate.

With data from more than 350,000 people and information about their genetics, education, socioeconomic status and disease history, this study had a solid methodology, said Dr. Aladdin Shadyab, associate professor of public health and medicine at the University of California, San Francisco. San Diego, who was not involved in the research.

It is well established that some people are genetically predisposed to a shorter lifespan. It is also well known that lifestyle factors, specifically smoking, alcohol consumption, diet and physical activity, can have an impact on longevity.

However, to date, there has been no research to decipher the extent to which a healthy lifestyle can counterbalance genetic risks.

“This study elucidates the essential role of a healthy lifestyle in mitigating the impact of genetic factors on the reduction of life span,” the researchers concluded.

Public health policies to improve healthy lifestyles would serve as powerful complements to conventional health care and mitigate the influence of genetic factors on human lifespan, the authors write.

The study involved more than 350,000 people from the UK Biobank and showed that those with a high genetic risk for a shorter life had a 21% higher risk of early death compared to those with a low genetic risk, regardless of their style of life.

The sample was made up of people of European ancestry, so it is limited in terms of the populations to which it can be applied.

The researchers gave each individual a polygenetic risk score, which summarizes the presence of several genes that have been found to have an impact on people’s lifespan, according to the study.

Study participants were also given a score based on how well they adhered to the principles of a healthy lifestyle, and were then followed for an average of 13 years to see if they had a short, intermediate lifespan or long.

All participants, regardless of genetic risk, were 78 percent more likely to die prematurely if they had an unhealthy lifestyle, the data showed.

For people who had both a genetic risk for a short lifespan and an unhealthy lifestyle, they were twice as likely to die prematurely as those with no genetic risk and a healthier lifestyle, a said Li, who is also director of Zhejiang University’s National Institute for Health and Medical Data Science.

People at genetic risk could extend their lifespan by up to 5.5 years with a healthy lifestyle, data showed.

“Adhering to a healthy lifestyle could substantially mitigate the reduction in lifespan for people genetically predisposed to a shorter lifespan,” Li said.

Meanwhile, people with unhealthy lifestyles are 78% more likely to die prematurely, regardless of genetic risk, researchers from China’s Zhejiang University School of Medicine and the University of Edinburgh found.

The study added that having an unhealthy lifestyle and genes with a shorter lifespan more than doubled the risk of early death compared to people with luckier genes and healthy lifestyles.

However, researchers have found that people seem to have some degree of control. The genetic risk of a shorter life span or early death can be offset by a favorable lifestyle by about 62%, they found.

“Participants at high genetic risk could extend their life expectancy by approximately 5.22 years at age 40 with a favorable lifestyle,” the researchers wrote.

The study followed people for an average of 13 years, during which more than 24,000 deaths occurred.

Participants were grouped into three categories of genetically determined lifespan, including long (20.1%), intermediate (60.1%), and short (19.8%), and three categories of lifestyle scores, including favorable (23.1%), intermediate (55.6%) and unfavorable (21.3%).

Researchers used polygenic risk scores to look at several genetic variants that generally genetically predispose a person to a longer or shorter life.

Other scores analyzed whether people smoked, consumed alcohol, exercised, what their body image was, whether they followed a healthy diet and aspects related to sleep.

The study was observational, meaning it could determine associations, but it couldn’t say for sure that these behaviors were the direct cause of changes in lifespan.

But the researchers were able to identify four factors that were associated with the greatest impact on the risk of premature death.

“The study identified an optimal lifestyle combination containing four lifestyle factors – no current smoking, regular physical activity, adequate sleep duration and a healthy diet – that provided better benefits for extending human life span” , said Li.

Adequate sleep was defined in the study as seven to eight hours per night. The current Physical Activity Guidelines for Americans recommend at least 150 minutes of moderate physical activity and two days of strength training per week for adults.

Moderate drinking is defined in the United States as a limit of two drinks per day for adult men and one drink per day for adult women, according to the US Centers for Disease Control and Prevention (CDC).

“This new research shows that despite genetic factors, a healthy lifestyle, including a nutritious balanced diet and maintaining an active lifestyle, can help us live longer,” said Matt Lambert, health information specialist at World Cancer Research Fund.