Our biological and chronological clocks may not be completely in sync, according to a new study from Stanford University, which found that humans age rapidly in at least two distinct periods: once at age 44 and again at age 60.
The study, published in the journalNature Aging, tracked the pace of molecular changes in 108 people between the ages of 25 and 75 over a median period of 1.7 years.
Although it’s a small sample, the results have serious health implications, given that the risk of cardiovascular disease, dementia, Parkinson’s, and other problems increases with age.
“We don’t just change gradually over time; there are some really dramatic changes,” Michael Snyder, director of Stanford University’s Center for Genomics and Personalized Medicine and lead author of the study, said in a statement. “It appears that middle age, around 40, is a time of dramatic change, as is the early 60s.”
These two periods are not exactly the same. For example, around age 40, there were changes in molecules associated with cardiovascular disease and lipid and alcohol metabolism, suggesting that people’s bodies break down alcohol and fat less efficiently once they reach this age.
At the same time, in the early 60s, there was a “rapid decline” in immune regulation, which could explain why older people are more vulnerable to disease.
Researchers also found that people 60 and older are more prone to kidney problems, type 2 diabetes, and cardiovascular disease.
Aging changes in men and women
The findings could help “clarify the changes we see in everyday life in the clinic,” Mirko Petrovic, chair of the department of internal medicine and pediatrics at Ghent University and president of the European Society of Geriatric Medicine, told Euronews. He was not involved in the study.
The researchers initially thought that the drastic changes around age 40 might be related to menopause or perimenopause, but when they analyzed the data, they found that these changes occurred in both women and men.
It’s worth noting that the study noted that lifestyle factors — such as alcohol and caffeine consumption and exercise levels — could contribute to these changes, and not just biological changes related to aging.
“A healthy lifestyle is very important for aging in general, [and] certain lifestyle interventions work better at certain ages,” said Joris Deelen, leader of the research group at the Max Planck Institute for the Biology of Aging in Germany. , for Euronews Health.
However, it’s not clear how inevitable these changes are or whether they happen at the same rate for people with different levels of health, according to Deelen, who was not involved in the study.
“We don’t know what it would look like for, say, very healthy or very unhealthy people, or how different it would be,” Deelen said.
The new findings are consistent with previous research on biological aging pathways, including a 2019 study that identified another peak around age 80.
“There is a huge level of interpersonal variability in old age,” Petrovic said.
A deeper understanding of how people age at the molecular level could help clinicians “predict what’s going to happen, make an early diagnosis, and also based on that, organize or prepare prevention strategies.”
