There May Be a Point in Life When Stress Ages You Fastest. The Pandemic Just Helped Us Find It.

On New Year’s Eve 2019, health officials in Wuhan, China, reported a mysterious cluster of pneumonia cases. It was the first sign of what would become the years-long Covid-19 pandemic. Across the world, every facet of life was interrupted, and many societies, including a growing anti-vaccine movement in the U.S., continue to grapple with the pandemic’s legacy, not to mention the millions of loved ones lost to the virus.However, a new study led by researchers at the Max Planck Institute in Germany suggests that the pandemic didn’t impact every age cohort equally—at least, according to four separate epigenetic clocks that measure age-related changes in DNA methylation patterns. This chemical process changes predictably as we age and is a standard measurement for gauging someone’s genetic age. The team got lucky with its timing. Just before the pandemic took hold in March 2020, a project called the TwinLife Epigenetic Change Satellite had collected DNA samples from children, adolescents, and young adults in Germany. It sampled them again through spring 2022.Senior author Elisabeth Binder studies how genes and the environment shape psychiatric disorders. She and her colleagues tracked how each age group’s epigenetic clocks changed over time. They also looked at data on socioeconomic background and physical health to see how pandemic stress affected each group. At first glance, the data showed some expected correlations between certain groups and health outcomes.“Across all age groups, stress was most significantly felt by those who were already at risk before the pandemic, whether due to poorer physical health, lower subjective well-being or lower socio-economic background” Binder said in a press statement.Because stress is a well-known driver of aging and key driver of inflammation, it wasn’t surprising that all age groups showed accelerated aging during one of the most stressful global eras in recent memory. But when the researchers dug deeper, they found something surprising. Adolescents showed more stress-related epigenetic aging than either children or young adults. According to the study, this suggests that mid-to-late puberty may be a pivotal window for “subjective stress-related alterations.”“This suggests that adolescence may be a time period that is especially sensitive to the effects of stress—this could be due to the changes happening in the body during puberty, or because lockdown measures, like restrictions on seeing peers, had a particularly strong impact on this age group,” Alicia Schowe, a post-doctoral researcher and lead author of the study, said in a press statement.The authors say lifestyle changes during lockdowns, such as less physical activity and weight gain, may also have played a role. But those factors alone can’t explain why adolescents showed more epigenetic aging than the other age groups.The findings are a reminder that human aging is complex—our biological age isn’t set by our genes alone. Events far beyond our control, like a global pandemic, can leave their mark too. As these young people grow further from the pandemic, researchers will keep following them to find out whether the years the virus added to their epigenetic clocks will fade or stay with them for life.Darren lives in Portland, has a cat, and writes/edits about sci-fi and how our world works. You can find his previous stuff at Gizmodo and Paste if you look hard enough.