A sister article in The Guardian highlights the two major waves of age-related changes at around ages 44 years and again at 60 years. The findings could explain why spikes in certain health issues including musculoskeletal problems and cardiovascular disease occur at certain ages.
see War Made Invisible: How America Hides the Human Toll of Its Military Machine by Norman Solomon
https://www.chevaliersbooks.com/book/9781620979167