Researchers zero in on more than a dozen factors that can predict how fast you’re aging — and have some ideas about what makes people age more slowly. Now researchers say that such perceptions aren’t just about outward appearances but about something deeper, there is a different pace at which each of us ages, and what that means for our health.

Study published in the Proceedings of the National Academy of Sciences. Scientists led by Daniel Belsky, an assistant professor of medicine at the Duke University School of Medicine’s division of geriatrics. Measured 18 factors tested in 20- and 30-year old that showed how quickly they are aging. The markers proved to be a good indicator of physiological age. They mirrored the biological effects of aging found in older people. Also good markers of physical age o   Meaning that those who aged faster also looked older, according to unbiased assessments by random people looking at their photos.

Most studies on aging, and the factors that affect aging, come from investigations of older populations. And in most cases, the chronic diseases or physiological changes that come with aging are already well established in these groups. It’s clear that aging doesn’t happen overnight but occurs gradually over a period of decades. 

The study:

• 954 people born in 1972 or 1973 in Dunedin, New Zealand
• Study followed them from age 26 to age 38.
• Each participant agreed to be tested on a range of 18 different factors that earlier studies have linked to aging
  • blood pressure
  • lung function
  • cholesterol 
  • body mass index
  • inflammation
  • integrity of their DNA 
  • Based on their scores on these measures, researchers calculated a biological age for each volunteer
  • They did this again when the people in the study were 32 and 38 years old, and combined them to calculate the pace at which each person was aging.

Results were that some people were biologically older and aging faster than others, despite being the same chronological age. Researchers gave 20- and 30-somethings the same tests of balance and thinking skills that gerontologists give for older adults, that these aging changes were the same as those occurring later in life.

Some people were actually biologically younger than their chronological age and aged more slowly than they should. The vast majority of factors affecting aging rates aren't genetic (almost 80%), meaning they're in our control. Study results will help researchers identify the causes of accelerated aging so that we might slow it down.

This study can also help us evaluate therapies that slow down aging. Now that researchers revealed a way to measure relatively and accurately the pace at which people age, it provides the rest of the research world a way of tracking anti-aging treatment works or not. 

Factors that affect the aging process and speed:

• Healthy diet that's low in fat and salt
• Maintaining a healthy weight
• Reducing stress
• Strong immune system
• Regular exercise
• Not smoking

This study group may be re-evaluated when participants are 45. Researchers continue to chart the participants diet, exercise and other behaviors.