Scientists are getting closer to understanding why our bodies age – and the answer could eventually help us stay healthier for longer.
Ageing was once largely viewed as an unavoidable process of wear and tear. But researchers now know that a complex series of changes takes place inside our cells as we grow older.
One increasingly influential theory puts the accumulation of molecular damage at the heart of the process.
A 2025 review published in Nature Aging argues that ageing may result from molecular errors and damage gradually building up as the body’s maintenance and repair systems become less able to keep everything working perfectly. Nature
This damage doesn’t occur in isolation. Researchers have identified a number of interconnected biological changes associated with ageing, including DNA damage, changes in the way genes are regulated, declining mitochondrial function, chronic inflammation and the accumulation of senescent or “ageing” cells that no longer function normally. Nature
The exciting part is that scientists have demonstrated in laboratory animals that some biological mechanisms involved in ageing can be altered.
That doesn’t mean researchers have discovered a way to stop human ageing – despite some attention-grabbing headlines.
Scientists are instead increasingly interested in extending healthspan: the number of years people spend living in good health, rather than simply extending lifespan.
Research is investigating drugs and other treatments targeting some of the biological processes associated with ageing. However, translating results from laboratory animals into safe and effective treatments for healthy humans remains a major challenge. The European Commission’s 2026 healthy ageing biotechnology program, for example, notes that despite decades of promising research, translating ageing science into successful clinical interventions has proved difficult. CORDIS
For now, some of the most convincing ways of supporting healthy ageing remain decidedly less futuristic.
Regular physical activity – including strength training – is associated with better health as we age, while researchers continue to investigate the effects of diet, sleep and other lifestyle factors on biological ageing. Recent research highlighted by BBC Science Focus points particularly to resistance exercise as a way of maintaining muscle and bone strength later in life. sciencefocus.com
So, have scientists finally discovered the single cause of ageing?
Not quite.
But understanding how damage accumulates – and how the body repairs it – is giving researchers new clues about whether some aspects of biological ageing might one day be slowed.
And increasingly, the goal isn’t eternal youth. It’s more healthy years to enjoy the life we already have.