From regular exercise regimes to strict dietary protocols, individuals have long pursued various strategies in the quest for a longer life. Now, a landmark scientific investigation has fundamentally shifted our understanding of longevity, revealing that the secret to an increased lifespan is predominantly encoded within our genes.
Reassessing the Genetic Contribution to Longevity
For decades, scientific consensus suggested that only between 10 and 30 per cent of a human lifespan could be attributed to genetic factors. The remaining majority was thought to be determined by a combination of illnesses, accidents, and crucial lifestyle choices such as maintaining a nutritious diet, abstaining from smoking, and engaging in consistent physical activity.
However, a transformative new study spearheaded by researchers at the University of Copenhagen has meticulously re-evaluated the actual role genetics play in determining human lifespan. According to their comprehensive calculations, the genetic contribution is significantly higher, accounting for approximately 55 per cent of an individual's longevity.
Implications for Ageing Research and Lifestyle Interventions
The study's co-authors, Daniela Bakula and Morten Scheibye-Knudsen, have articulated the profound implications of these findings. 'If lifespan is largely fixed by genetics, then the scope for influencing the rate of ageing is limited, particularly for lifestyle interventions,' they stated. 'Conversely, if genetic contributions are minimal, efforts to understand ageing through genetic approaches are difficult to justify.'
This revelation carries substantial weight for public health strategies and personal wellness planning, suggesting that genetic predisposition may play a far more dominant role than previously acknowledged.
Analysing Lifespan Data in the Modern Context
The research team embarked on this study to precisely understand why some individuals live considerably longer than others. They noted that many historical studies relied on centuries of potentially unreliable data, often including periods where deaths from disease and inadequate healthcare were far more prevalent, which could skew the perceived influence of non-genetic factors.
To obtain a clearer picture, the Copenhagen team employed a robust methodology, analysing twin studies. Their analysis revealed a critical pattern: when mortality from external factors—such as accidents or infectious diseases—is reduced, the relative importance of genetic factors in determining lifespan becomes markedly more apparent and increases.
UK Life Expectancy and Healthy Living
This research emerges against a backdrop of steadily increasing average life expectancy in the United Kingdom over recent centuries. According to the most recent data from the Office for National Statistics (ONS), the male healthy life expectancy (HLE) at birth in England for the period 2021 to 2023 is estimated at 61.5 years. For females in England during the same period, the healthy life expectancy is slightly higher, standing at 61.9 years.
Scientific and Societal Ramifications
In an accompanying editorial, the researchers emphasised that these findings 'carry important implications' for both biological science and societal expectations. 'Clarifying the role of inherited variation in ageing-related mortality is therefore central to both biological understanding and societal expectations,' they wrote.
The experts argue that this new work strengthens the scientific case for intensifying research into specific genetic variants associated with a long life. It also supports investigating which genetic differences impact the fundamental biological pathways that regulate the ageing process itself.
Connections to Other Complex Human Traits
Notably, the study's estimated 55% heritability for lifespan aligns with the observed approximate 50% heritability of other complex human traits. 'Perhaps this means that intrinsic rates of ageing are tightly optimised through evolution, in line with other traits such as cognitive function and metabolism,' the researchers added, suggesting a deep evolutionary underpinning for the genetic control of longevity.
This groundbreaking analysis challenges long-held assumptions and redirects the scientific focus towards the powerful genetic blueprint that significantly shapes our journey through life, offering a new paradigm for understanding the very foundations of human ageing and longevity.
