Your Lifestyle, Not Your Genes, May Be the Biggest Factor in How Long You Live

In a revelation that challenges common assumptions about aging and mortality, new research shows that environmental factors like smoking, physical activity, and living conditions have a substantially greater impact on lifespan than genetic predisposition. The study, published in Nature Medicine, found that environmental factors explain 17% of the variation in mortality risk, while genetic factors account for less than 2%.

Researchers analyzed data from nearly half a million UK Biobank participants, examining 164 environmental factors and genetic risk scores for 22 major diseases. The study, led by researchers from Oxford Population Health, represents the most comprehensive investigation to date of how lifestyle and environmental factors influence aging and premature death.

Key Environmental Drivers of Aging

The research team identified 25 independent environmental factors that significantly affect mortality and biological aging, with 23 of these being potentially modifiable. Smoking emerged as the most significant risk factor, associated with 21 different diseases. Socioeconomic factors, including household income and home ownership, were linked to 19 diseases, while physical activity influenced 17 diseases.

“Our research demonstrates the profound health impact of exposures that can be changed either by individuals or through policies to improve socioeconomic conditions, reduce smoking, or promote physical activity,” says Professor Cornelia van Duijn, senior author of the paper and St Cross Professor of Epidemiology at Oxford Population Heath.

Early Life Impact

Perhaps most striking were the findings about early life exposures. The study revealed that body weight at age 10 and maternal smoking during pregnancy influence aging and mortality risk 30-80 years later. This suggests that environmental factors begin accelerating aging early in life, though there remains ample opportunity for prevention.

Disease-Specific Patterns

The research uncovered interesting variations in how environmental and genetic factors influence different diseases. Environmental exposures showed a stronger effect on diseases of the lung, heart, and liver, while genetic risk dominated for conditions like dementia and breast cancer.

“Your income, postcode and background shouldn’t determine your chances of living a long and healthy life,” notes Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, who was not involved in the study. “But this pioneering study reinforces that this is the reality for far too many people.”

Novel Research Methods

The study employed an innovative “aging clock” that monitors aging rates using blood protein levels. This measurement tool, previously validated in studies from China and Finland, allowed researchers to connect environmental exposures that predict early mortality with biological aging processes.

Dr. Austin Argentieri, the study’s lead author, emphasizes the significance of their comprehensive approach: “Our exposome approach allowed us to quantify the relative contributions of the environment and genetics to aging, providing the most comprehensive overview to date of the environmental and lifestyle factors driving aging and premature death.”

Future Implications

While individual environmental factors may each play a relatively small role in determining lifespan, their combined effect is substantial. This suggests that integrated strategies addressing multiple environmental factors could significantly improve population health outcomes.

The findings lay groundwork for more targeted public health interventions and policy changes. They also highlight the potential for individuals to influence their aging trajectory through lifestyle modifications, regardless of genetic predisposition.

The research was conducted through a collaboration between Oxford Population Health and researchers from the University of Oxford, Massachusetts General Hospital, the Broad Institute, the University of Amsterdam, Erasmus University Rotterdam, and the University of Montpellier.