Part of the secret to ageing gracefully could centre on being exposed less to harmful substances in the environment, chemicals such as benzene, cigarette smoke, and even stress.
Chronological age might mean little in terms of the biological age of a person's body and cells, say researchers.
What is needed is a better understanding of chemicals involved in ageing and biomarkers to measure their effects, say the scientists in the Cell Press journal Trends In Molecular Medicine. "The rate of physiologic, or molecular, ageing differs between individuals in part because of exposure to 'gerontogens', environmental factors that affect ageing," said Dr Norman Sharpless from the University of North Carolina, Chapel Hill.
"We believe just as an understanding of carcinogens has informed cancer biology, so will an understanding of gerontogens benefit the study of ageing. By identifying and avoiding gerontogens, we will be able to influence ageing and life expectancy at a public health level."
In the future, blood tests evaluating biomarkers of molecular age might be used to understand differences among individuals in ageing rates, he said. Cigarette smoke is likely the most important gerontogen, he noted. UV radiation makes people older too, as does chemotherapy treatment, he added.
Compiled by Chang Ai-Lien
This article was first published on June 1, 2014. Get a copy of The Straits Times or go to straitstimes.com for more stories.