Two real milestones with “spectacular” changes: what are the key ages when human beings suddenly age ?

44 ans et 60 ans : ces âges où on vieillit le plus vite

Aging and the occurrence of diseases associated with it are not governed by a linear process. According to the results of an American study, the aging of the skin, muscles, the body's ability to metabolize lipids or alcohol… peaks at ages 44 and 60.

Aging is associated with a risk of developing chronic diseases; cardiovascular, neurodegenerative, metabolic, joint… A team of researchers from Stanford University School of Medicine (United States) has taken an interest in this aging. Is it linear or, on the contrary, can we, with reason, have the impression that we age 10 years overnight ?

"The analysis revealed consistent nonlinear patterns in molecular markers of aging, with significant deregulation occurring at two main periods occurring at approximately age 44 and 60,", note the authors of the study, whose results were published on August 14 in the journal Nature aging.

The researchers analyzed some 135,000 molecules (proteins, cytokines, metabolites, etc.) and microbiota (viruses, fungi, bacteria) in 108 people aged 25 to 75. They regularly had blood samples and other biological materials taken. These were analyzed using new high-throughput omics technologies, which make it possible to obtain complete and global biological information from a sample and to understand it using artificial intelligence.

“Spectacular” changes

In total, 81% of the molecules and microorganisms analyzed showed nonlinear fluctuations, and decreased or increased more rapidly at certain ages of life, 44 and 60 years. These changes were found in both men and women. These developments, considered "spectacular" by Professor Michael Snyder, geneticist and lead author of the study, occur "whatever class of molecules you are examining".

In detail, among the most significant changes, we find, at age 40, the molecules linked to:

alcohol metabolism; caffeine metabolism; lipid metabolism; cardiovascular diseases; skin; muscles.

A higher alcohol consumption after age 40 ?

In people aged 60, the most spectacular changes were those of the molecules linked to:

carbohydrate metabolism; caffeine; regulation of immunity; renal functions; cardiovascular diseases; skin; muscles.

The research team does, however, acknowledge some biases. For example, the decline in alcohol metabolism could be linked to higher alcohol consumption after age 40. While scientists intend to explore the factors behind these changes, these results may encourage people to pay more attention to their health at these key ages in life, such as exercising to maintain muscle mass.

In addition, understanding the role played by alterations of these molecules in the mechanisms of aging (and the onset of age-related diseases) can be used to develop new therapies.