The leak

You are born with it. You leak about 1.5% a year.

HA is how the body holds water. Collagen is the scaffolding. Hyaluronic acid is highest at birth and leaks about 1.5% of that peak every year — so by sixty most of the infant store is gone. Skin collagen climbs to a peak around twenty, then falls. About half of that peak is still there by the mid-seventies. Production itself slows roughly one percent a year from early adulthood.