One bad day at work can literally age your body by years.
A new study has shown for the first time that stress can make our cells look up to five years older in one day.
Fortunately, a good night’s sleep compensates for most of the damage.
But the study undermines the idea that our biological clocks, as we currently understand them, are a perfect way to measure our “real” age.
This new study shows that people’s epigenetic clocks produce different readings throughout a day. Previously, this measurement was thought to be stable across daily changes.
Epigenetic clocks look for invisible changes in our DNA that scientists can interpret as a measure of the age of our cells.
While some people measure their age in years and others in smile lines, scientists are a little more complicated than that.
They say the most important measure is actually your biological age.
Biological age is determined by unwinding our DNA and detecting small changes. This is called our epigenetic clock.
Think of these changes like rust on a nail or scratches on a CD – just on a microscopic level.
Over a lifetime, people accumulate changes in their clocks — until now, scientists thought your epigenetic clock was pretty much stable in the short term, Art Petronis, a chronoepigeneticist at the University of Toronto, Canada, and Vilnius University in Lithuania told PNAS.
But it turns out that these clocks may also be sensitive to changes that happen throughout the day, according to Dr. Petronis, which was published in the peer-reviewed journal called Aging cell.
So sensitive, in fact, that one day’s stress can cause a person to undergo five years of genetic changes in a 24-hour period.
This is what aging looks like at the DNA level, because stressors cause small tags and changes to be added to your genetic code. Scientists can identify these markers from blood.
But this doesn’t mean that one particularly stressful day at work will take years off your life.
It does mean that you may want to take those biological aging tests out of your shopping cart, because if someone’s biological age can fluctuate so extremely in any given day, taking a measurement at any time may not give you an accurate idea of how ‘old’ those are really your cells.
This is especially important because epigenetic clock testing is currently being used ‘with abandon’ in laboratories. Trey Ideker, a geneticist at the University of California, San Diego, who was not involved in the study, told PNAS.
Also, several companies have popped up around the world offering at-home tests for people curious about their cellular aging.
This is the same testing genre that Will and Jada Smith talked about on a 2019 episode of Red Table Talk — and that predicted UFC president Dana White had only 10 years to live.
A company called Tally Health offers one for $249. Another, called Novos, offers an epigenetic test for $349 each.
On the cheap side, you can buy the TruMe Biological Age Test from ProHealth for $99.
There is still “far too much” we don’t understand about the science of epigenetics for these tests to be considered accurate, Professor Ideker said.
“It is a study that I have been waiting for for a long time,” said Professor Ideker.
Dr. Petronis and his team reached their conclusions by taking blood samples from a 52-year-old man every three hours – resulting in 24 samples to be searched.
They performed 17 different tests on each of the samples, each indicating a different epigenetic change.
In 13 of those tests, the researchers saw a major change over a 24-hour period.
Overnight, the epigenetic clocks appeared on their youngest. During the day the bells seemed older and older, with a peak in age around noon.
For example, if you take an epigenetic test around noon, your results may give the impression that you are much older than you actually are.
We all exist on a somewhat fluctuating scale of epigenetic changes, and not at one static age, the study suggests. Dr. Petronis said this study needs to be repeated with more people to find out how much it applies to the average person.
But for now, he hopes it “opens the door” to a big question about epigenetic clocks.