Day of the Antler

It has long been my opinion that we don't age linearly, that is, the gradual degradation of our bodies doesn't proceed at a constant rate from the peak of adult maturity to old age.  It seems to occur in sudden, random destructive spikes - a disease from which we never fully recover, a fall, or the catastrophic failure of one organ or the other. I call this conjecture "Punctuated Aggregational Destruction," and if we plotted our body's decline over the years, the line's not a steady downward slope but rather a flat line interrupted by the occasional downward step at each PAD event.

So it was with "told-you-so" interest that I saw an article in The Guardian today that reported on the results of an ageing-related study. The study tracked thousands of different molecules in people aged 25 to 75, and found two major waves of age-related changes at around ages 44 and again at 60. The findings could explain why spikes in certain health issues, including musculoskeletal problems and cardiovascular disease, occur at certain ages.

“We’re not just changing gradually over time. There are some really dramatic changes,” said Prof Michael Snyder, a geneticist and director of Stanford University's Center for Genomics and Personalized Medicine.

The mid-40s PAD event was unexpected and initially assumed to be a result of perimenopausal changes in women skewing results for the whole group. But the data revealed similar shifts were happening in men in their mid-40s, too. This suggests that while menopause may contribute to the changes observed in women in their mid-40s, there are likely other, more significant factors influencing these changes in both men and women.

The second PAD event included molecules involved in immune regulation, carbohydrate metabolism, and kidney function. Molecules linked to skin and muscle ageing changed at both time points. Previous research suggested that a later PAD event may occur around the age of 78, but the recent study did not confirm this.

The evidence indicates that the risk of many age-related diseases does not increase incrementally, with Alzheimer’s and cardiovascular disease risk showing a steep uptick after 60. Some of the changes could be linked to lifestyle or behavioral factors. For instance, the change in alcohol metabolism could result from an uptick in consumption in people’s mid-40s, which can be a stressful period of life.