At One Place

Body water

Body water
About 60% of an adult male by mass, 55% of an adult female.

Water is the medium for essentially every biochemical process, transports nutrients and waste, cushions joints and organs, and carries heat to the skin for cooling.

The numbers

Adult male
about 60%
Adult female
about 55%
Newborn
about 75%
Brain and heart
about 73%
Bone
about 31%

Worth knowing

The male–female difference is not about hydration but body composition: fat tissue holds much less water than muscle, and women carry a higher proportion of body fat on average. The figure falls with age, from about 75% at birth to nearer 50% in later life.

Structural reference only — this is not medical advice, and individual variation in every figure here is substantial. Anything concerning your own health belongs with a clinician rather than a reference page.

Common questions

What does the body water do?
Water is the medium for essentially every biochemical process, transports nutrients and waste, cushions joints and organs, and carries heat to the skin for cooling..
Body water — key numbers
Adult male: about 60%. Adult female: about 55%. Newborn: about 75%. Brain and heart: about 73%. Bone: about 31%.

Related pages

Sources

  1. Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked