- The secret to extend life expectancy lies in
the DNA, claims a new study
- DNA methylation is a biomarker
for biological age, which can predict the risk of early
- An epigenetic clock calculates the aging of blood,
cells, and tissues and compares with chronological age to predict a person's
People today have started to follow a healthy
lifestyle to keep diseases away and increase lifespan. But some individuals who
lead a healthy lifestyle die young, and the reason is unknown. To find out the
reason for early death, a team of International researchers conducted a study.
The researchers claim that the answer to early death lies in the DNA.
According to the World Health Organization,
globally, the number of people over age 65 will outnumber those under age
five by 2017. The global population over 60 will double from 11 to 22 percent
‘A healthy lifestyle may not increase a persons lifespan. Accelerated biological aging increases the risk of early death.’
"Many countries will be ill-prepared to keep
pace with the high costs associated with disease and disability as more people
live longer," said Steve Horvath, a geneticist at UCLA.
Horvath led a team of 65 scientists in seven
countries to record age-related to DNA, calculate biological age (physiological age of the body) and estimate a person's lifespan. "Our research reveals valuable
clues into what causes human aging, marking a first step toward developing
targeted methods to slow the process," said principal investigator Horvath, a
professor of human genetics and biostatistics at UCLA's David Geffen School of
Medicine and Fielding School of Public Health.
Epigenetic Clock Predicts a Person's Life
The epigenetic clock was developed by Horvath
in 2013. The clock is a multi-tissue predictor of age that estimates the DNA
methylation age of most blood, tissues, and other cell types. Methylation
is a natural process that chemically alters the DNA over time. The clock was
developed using 8,000 samples from 82 Illumina DNA methylation array datasets,
encompassing 51 healthy tissues and cell types.
For the current study, scientists collected
data from the Framingham Heart Study and Women's Health Initiative that
analyzed the DNA in the blood samples collected from more than 13,000 people in
the United States and Europe. Using an epigenetic clock and other molecular
methods, the scientists measured the aging rate of every individual. The scientists
used the epigenetic clock to predict a person's lifespan by comparing
chronological age to biological age
Brian Chen, first author and a postdoctoral
fellow at the National Institute on Aging, said "We were stunned to see that
the epigenetic clock was able to predict the lifespans of Caucasians,
Hispanics and African-Americans.
This rang true even after adjusting for
traditional risk factors like age, gender, smoking, body
, disease history and
blood cell counts."
The findings showed that about five
percent of the population ages at a faster biological rate, resulting in early
death. Accelerated aging increases the risk of death by 50% at any age
The study explains why some people die
prematurely, despite following a nutritious diet, regular physical activity,
moderate drinking and without smoking. A healthy lifestyle may help extend life
expectancy, but, the biological aging process may increase the risk of early
death. "Yet risk factors like smoking, diabetes, and high blood pressure still
predict mortality more strongly than one's epigenetic aging rate," said
Studies have been carried out to identify
biomarkers for biological age for years, said co-author Dr. Douglas Kiel, a
professor at Harvard Medical School and a senior scientist at the Institute of
Aging Research at Hebrew SeniorLife.
"In geriatric medicine, we are always struck
by the difference between our patients' chronological age and how old they
appear physiologically. This study validates the use of DNA methylation as a
biomarker for biological age. And if we can prove that DNA methylation
accelerates aging, we can devise strategies to slow the rate and maximize a
person's years of good health," said Kiel.
Co-author Dr. Themistocles Assimes, an
assistant professor of cardiovascular medicine at Stanford University School of
Medicine, said, "The role of epigenetic
and life expectancy remains unknown. Do the epigenetic changes associated with
chronological aging directly cause death in older people? Perhaps they merely
enhance the development of certain diseases--or cripple one's ability to resist
the progression of disease after it has taken root. Future research is needed
to address these questions."
"We must find interventions that prolong
healthy living by five to 20 years. We don't have time, however, to follow a
person for decades to test whether a new drug works. The epigenetic clock would
allow scientists to quickly evaluate the effect of anti-aging therapies in only
three years," said Horvath.
The study is published in the journal
Ways to Reduce Biological Age
Biological age is the actual age of the body.
Some of the factors such as stress, fitness, nutrition, sleep pattern and
relationship have an impact on the biological age.
- Lower your stress levels
- Eliminate toxins from the
- Include antioxidant rich fruits and
vegetables in the diet
- Drink plenty of water
- Engage in regular exercise
- Sleep for
at least 7 hours
- Think positive
- DNA methylation age of human tissues and cell types