If you’ve suddenly noticed more wrinkles, aches and pains, or just felt like you’ve aged almost overnight, there may be a scientific explanation: Research shows that aging isn’t a slow and steady process, but rather occurs in at least two sudden accelerations.
The study, which tracked thousands of different molecules in people between the ages of 25 and 75, detected two major waves of age-related change, one around age 44 and another at age 60. The findings may explain why certain health problems, such as musculoskeletal problems and cardiovascular disease, spike at certain ages.
“We’re not just seeing gradual changes over time. We’re seeing really dramatic changes,” said Professor Michael Snyder, a geneticist and director of Stanford University’s Center for Genomic Sciences and Personalized Medicine, and lead author of the study.
“We found that the mid-40s was a time of dramatic change, as was the early 60s, and this was true no matter what class of molecules we looked at.”
The study followed 108 volunteers who provided blood and stool samples, as well as skin, oral, and nasal swabs every few months for anywhere from one to nearly seven years. The researchers assessed 135,000 molecules (RNA, proteins, and metabolites) and microbes (bacteria, viruses, and fungi that lived in the participants’ guts and on their skin).
Most molecular and microbial abundance did not change gradually over time: When the scientists looked for molecular clusters that showed the most significant changes, they found that these tended to occur in people between their mid-40s and early 60s.
The sudden increase in ageing in the mid-40s was unexpected and initially thought to be the result of perimenopause changes in women skewing the results for the entire group, but the data revealed that similar changes were occurring in men in their mid-40s as well.
“This suggests that while menopause or the peri-menopause may contribute to the changes seen in women in their mid-40s, there are likely other more important factors influencing these changes in both men and women,” said Dr. Xiaotao Shen, lead author of the study and a former postdoctoral research fellow at Stanford University School of Medicine, now at Nanyang Technological University in Singapore.
The first wave of changes included molecules related to cardiovascular disease and the ability to metabolize caffeine, alcohol, and lipids. The second wave of changes included molecules involved in immune regulation, carbohydrate metabolism, and kidney function. Molecules related to skin and muscle aging were altered at both time points. Previous studies have shown that at later times Rapid increase in aging population It may occur around the age of 78, but this could not be confirmed in the latest study as the oldest participant was 75 years old.
This pattern is consistent with previous evidence that the risk of many age-related diseases does not increase gradually, with Alzheimer’s and cardiovascular disease risks rising sharply after age 60. It is also possible that some of the changes are related to lifestyle and behavioral factors: for example, changes in alcohol metabolism could result from increased consumption in the mid-40s, which can be a stressful period in life.
The findings could help target interventions, such as increasing exercise during periods of rapid muscle loss, the authors say. “I’m a big believer in trying to make lifestyle adjustments while you’re healthy,” Snyder said.
The findings have been published in the journal Natural aging.
