Anyone who has ever attended a high school reunion will notice one thing -- how different everyone looks. Though attendees are the same age, some inevitably will look years beyond their true age while some will look as though they haven't changed at all.
Findings from a long-term study, published this week in the Proceedings of the National Academy of Sciences, say real aging is what occurs within your organs, which might translate to your appearance.
A team of international researchers from the U.S., U.K., Israel and New Zealand looked at over 950 subjects born in the early 1970s, and studied 18 different biological factors that possibly impact the aging process.
They looked at things like kidney, liver and metabolic function, as well as things like the cholesterol and fitness levels of the subjects, at various ages between 26 and 38.
Using these measures, they assigned each subject a composite biological age, with the "youngest" being 30 and the "oldest" being 60. Some subjects were aging normally, at a rate of one year per year. But some were aging as fast as three years per chronological year. In addition, those people who were aging faster often exhibited other age-specific problems like trouble with balance or problem-solving.
What's more is that the researchers had Duke University students look at photos of the 38-year-old subjects and guess their age. Those who were aging faster -- or more poorly on the inside -- were also perceived to be older.
"There's a great deal of environmental influence," the study's lead author, Dan Belsky of Duke University's Center for Aging, said in a statement. So that's the good news and the bad news, depending on how you look at it. Aging can't be totally chalked up to your genes.
The findings seem to suggest that minding your health and keeping diseases at bay could keep you looking and feeling young.
Other studies have also shown the importance of healthy choices in aging. One study found that adopting healthy habits like a balanced diet, meditation and exercise could even reverse cell aging. Similarly, another study found that unhealthy habits like drinking sugary sodas speed up aging.
Researchers say studying younger people is critical for understanding aging and how to prevent age-related diseases. In this cohort, for example, signs of internal aging were observed as early as 26.
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