This research has been published in a magazine named ‘Science’. It states that if we remove deaths caused by accidents, infections and other external causes, then about 55% of human lifespan is genetic. This means that more than half of the difference in people’s age is due to genes. This is much higher than previous research, in which this figure was stated to be only 10-25%.
These results have been obtained by analyzing more than 100 years of data of twins from Denmark and Sweden. Scientists looked at twins who grew up together and who grew up separately. They also studied the siblings of people who lived more than 100 years. Most people were born between 1870 and 1935. At that time, deaths due to infectious diseases and accidents were very high.
important role of genes
When scientists separated out deaths caused by external causes and looked only at deaths related to biological aging, the true impact of genes came to light. They found that identical twins were very similar in age. This also shows why the effect of genes on age is more clearly visible today. This is because deaths due to infection, violence and accidents have reduced. Therefore, the role of genes in determining age has become more visible.
What do experts say?
Indian experts say that these results will have a big impact on public health. Dr. Anoop Mishra, Chairman, Fortis C-Doc, says that genes play a big role in biological ageing. But they warn that conditions in India may reduce this advantage.
- Dr. Mishra explains, ‘Leaving aside external factors, half of a person’s lifespan is determined by genes, but poor nutrition, air pollution and increasing diabetes and obesity can negate the benefits of genes and accelerate the process of biological ageing.’
- Dr. Ambrish Mithal, Group Chairman, Endocrinology and Diabetes, Max Healthcare, says that aging is a balance between inheritance and environment. ‘Genes set an upper limit on lifespan, while epigenetics and lifestyle determine how close we get to that limit,’ he explains. Epigenetics means that external factors can turn genes on or off without changing the DNA.
- Scientists say that these results do not mean that your age is decided by birth. Almost half of the age difference is still determined by lifestyle, availability of health services and living conditions. However, research suggests that genes set a kind of ‘biological ceiling’, and environment determines whether people reach that ceiling or not.
- Researchers believe that these results can give new direction to the ongoing debates about aging and longevity. At the same time, it also underlines the need to deal with the threats that reduce our biological age.
