How the Body Changes From Birth to Old Age

Oxygen Shift: Newborns switch instantly from placental oxygen to lung breathing at birth.
Bone Boom: Babies have 270 bones—many fuse into 206 by adulthood.
Immune Build: Childhood introduces thousands of new microbes that train the immune system.
Muscle Peak: Strength typically peaks in your late twenties before gradual decline.
Vision Clarity: Eyes mature through childhood, achieving full focus around age six.
Metabolism Map: Your metabolism peaks in childhood, slows in adulthood, and drops sharply after 60.
Heart Story: The heart thickens slightly with age, pumping less efficiently over time.
Skin Shift: Collagen decline begins as early as the mid-20s, softening elasticity.
Brain Curve: Cognitive processing speed peaks in early adulthood, while wisdom grows with age.
Aging Arc: Older bodies repair slower, but lifestyle can greatly shape how aging unfolds.