Your Biological Clock: Why Some Age Faster Than Others
WEDNESDAY, Sept. 28, 2016 -- Some adults age faster biologically than others, and may die early even if they have healthy lifestyles, researchers report.
The international team of scientists analyzed DNA in blood samples from more than 13,000 people in the United States and Europe and used an "epigenetic clock" to predict their life spans.
The clock calculates the aging of blood and other tissues by tracking a natural process (methylation) that chemically alters DNA over time, the researchers explained.
"We discovered that 5 percent of the population ages at a faster biological rate, resulting in a shorter life expectancy," said principal investigator Steve Horvath. He is a professor of human genetics and biostatistics at the University of California, Los Angeles.
"Accelerated aging increases these adults' risk of death by 50 percent at any age," Horvath added in a university news release.
"While a healthful lifestyle may help extend life expectancy, our innate aging process prevents us from cheating death forever," he said. "Yet risk factors like smoking, diabetes and high blood pressure still predict mortality more strongly than one's epigenetic aging rate."
The study was published Sept. 28 in the journal Aging.
"We were stunned to see that the epigenetic clock was able to predict the lifespans of Caucasians, Hispanics and African-Americans," said study first author Brian Chen, a postdoctoral fellow at the U.S. National Institute on Aging.
"This rang true even after adjusting for traditional risk factors like age, gender, smoking, body mass index, disease history and blood cell counts," Chen added.
Horvath said the research appears to reveal valuable clues into what causes human aging. This marks "a first step toward developing targeted methods to slow the process," he added.
The preliminary findings may help explain why some adults die young even if they have a nutritious diet, get regular exercise, don't smoke and drink little or no alcohol.
Larger studies are needed to help scientists tease out the relationship between biological age and specific diseases, the study authors added.
The American Academy of Family Physicians offers tips for staying healthy.
Posted: September 2016