A new study by Stanford Medicine reveals that ageing doesn’t happen in a smooth, continuous process—it actually speeds up at certain key life stages. Contrary to the long-held belief that ageing is a steady, gradual decline, the research found that our bodies undergo two notable accelerations in ageing—around the mid-40s and early 60s. These shifts are marked by dramatic changes in molecules and microorganisms that influence everything from metabolism to immunity.
The researchers initial study followed 108 participants, ages 25-75, collecting biological samples every few months over multiple years, then quantitatively analyzing over 135,000 molecules and microbiomes. This generated around 250 billion data points and showed that 81% of the molecules followed changed substantially at two ages, roughly 44, and 60. When these shifts happened there were larger impacts to health in domains like cardiovascular function, skin, muscle tone, and metabolism.
In a new study by Stanford Medicine it was found that aging doesn’t occur as a smooth continuum. Instead, it can speed up at certain critical points throughout life. The researchers found that aging is not believed to occur at a steady, gradual decline. Instead, it was discovered there are actually two significant accelerations of aging of our bodies around the mid-40s, and early 60s. All of this happens with greatly reduced levels of various molecules and microbiomes that govern scientists right to everything from metabolism to immunity.
Midlife and early senior years mark major biological turning points
The interesting and new part of this research is that the same kind of aging accelerations occurred consistently in both males and females. Initially the researchers assumed the mid-40s changes for women were due to menopause or perimenopause, however further review of the data suggested that males were also impacted at mid-40s in similar directions.
Michael Snyder, PhD, the study’s senior author, emphasized the significance of these findings. “We’re not just changing gradually over time; there are some really dramatic changes,” he noted. During the mid-40s, changes linked to alcohol and caffeine metabolism, skin and muscle health, and cardiovascular pathways became evident. By the early 60s, the body showed signs of further transformations—this time impacting carbohydrate metabolism, immune system function, kidney health, and more.
This study not only sheds light on how we age, but also when. Understanding these critical life stages may lead to earlier interventions and targeted health strategies, helping people manage ageing more proactively and possibly even slow down some of its impacts.
