Baby Bones vs. Adult Bones: Understanding Bone Development

Newborn bones are softer—higher water content (~90%), less mineralization (~10% calcium/phosphate). They're more flexible, with more cartilage.

During childhood, bones ossify: cartilage replaces with mineralized matrix. Peak bone mass achieved ~age 25–30. Adult bones are harder, more brittle, with lower water content.

This developmental trajectory explains why children's fractures differ (greenstick, buckle) and why adequate calcium, vitamin D, and weight-bearing exercise during growth are critical for lifelong skeletal health.