Researchers at the University of Southern California report that a person's body-age can deviate from their chronological age by over 40 years.
Speaking about her team's study, Eileen Crimmins, Professor of Gerontology at the University of Southern California told express: 'Some people who are 57 or older look like they're in their twenties, while some people look like they're over 100, and there's a big range in between.'
The team behind this research used epigenetic factors as indicators of age.
The researchers looked at the rate and amount of modification occurring to the DNA of more than 4000 over-57s and found that there were often striking differences between an individual's biological age and their chronological age.
Factors such as pollution, smoking and stress were found to drive body-ageing, however being obese was the largest found driver of body-ageing, accelerating ageing by up to 18 months.
Crimmins said at the American Association for the Advancement of Science conference in Seattle, 'We think that adverse social experiences can change your epigenetic profile in ways that may subsequently influence your health adversely.'
The researchers concluded that people do not age at the same rate and our behaviour is far more indicative of our biological age than chronological age alone.
This research suggests that there might be room to lower your biological age by modifying your lifestyle.
As Professor Crimmins explained: 'Epigenetic age may be changeable with behavioural changes. For example, if obesity raises epigenetic age, losing weight may lower it. People do hope to move some of these findings to clinical trials.'
The study also produced some inexplicable findings, suggesting for example that low socioeconomic status in childhood and having a drinking problem delayed ageing. Full findings of the study are due to be published in March.