If you've ever felt like everything in your body is breaking down at once, that might not be your imagination. A new Stanford Medicine study shows that many of our molecules and microorganisms dramatically rise or fall in number during our 40s and 60s. Researchers assessed molecules from people aged 25 to 75, as well as their microbiomes — the bacteria, viruses and fungi that live inside us and on our skin — and found that the abundance of most molecules and microbes don’t shift in gradual, chronological order. Rather, we undergo two periods of rapid change during our lifespan — at around age 44 and again at age 60. "We’re not just changing gradually over time; there are some dramatic changes,” said Michael Snyder, Professor of Genetics and the study’s author. That so many dramatic changes happen in the early 60s is perhaps not surprising, Snyder said, as many age-related disease risks and other age-related phenomena are known to increase at that point in life. However, the large cluster of changes in the mid-40s was somewhat surprising to scientists. Significant changes were seen in the number of molecules related to alcohol, caffeine and lipid metabolism, cardiovascular disease, and skin and muscle. It’s possible some of these changes could be tied to lifestyle or behavioral factors that cluster at these age groups, rather than being driven by biological factors. whatever their causes, the existence of these clusters points to the need for people to pay attention to their health, especially in their 40s and 60s, the researchers said. That could look like increasing exercise to protect your heart and maintain muscle mass at both ages or decreasing alcohol consumption in your 40s as your ability to metabolize alcohol slows. The team plans to further explore the drivers of these clusters of change.
