Water is virtually everywhere from soil moisture and ice caps , to the cells inside our own bodies . Depending in factors like location , fat index , age and sex , the average human is between 55-60% water . At birth , human babies are even wetter . Being 75 % water , they are swimmingly similar to fish . But their water composition drops to 65% by their first birthday . So what role does water play in our bodies , and how do we actually need to drink to stay healthy ?
The h2o in our bodies work to cushion and lubricate joints, regulate temperature , and to nourish the brain and spinal cord . Water isn’t only in our blood . An adult’s brain and heart are almost three quarters water .   That’s roughly equivalent to the amount of moisture in a banana . Lungs are more similar to an apple at 83% . And even seemingly dry human bones are 31% water .
If we are essentially made of water , and surrounded by water , Why do we still need to drink so much ? Well , each day we lose two to three litres through our sweat , urine and bowel movement , and even just for breathing . While these functions are essential to our survival , we need to compensate for the fluid loss . Maintaining a balanced water level is essential to avoid dehydration or over-hydration , both of which can have devastating effects on overall health . At first detection if low water level ,sensory receptors in the brain’s hypothalamus signal the release of antidiuretic hormone . When it reaches the kidneys , it creates aquaporins , special channels that enables blood to absorb and retain more water , leading to concentrated , dark urine . Increase dehydration can cause notable drops in energy ,mood , skin moisture ,and blood pressure , as well as signs of cognitive impairment . A dehydrated brain works harder to accomplish the same amount as a normal brain , and it even temporarily shrinks because of its lack of water . Over-hydration or hyponatremia , is usually caused by overconsumption of water in a short amount if time . Athletes are often the victims of over-hydration because of complications in regulating water levels in extreme physical condition . Whereas the dehydrated brain amps up the production of antidiuretic hormone , the over-hydrated brain slows , or even stops , releasing it into the blood . Sodium electrolytes in the body becomes diluted , causing cells to swell . In severe cases , the kidneys cant keep up with the resulting volumes if dilute urine . Water intoxication then occurs , possible causing headache , vomiting and , in rare instances , seizures or death . But thats pretty extreme situation . On a normal , day-to-day basis , maintaining a well-hydrate system is easy to manage for those of us fortunate enough to have access to clean drinking water .
For a long time , conventional wisdom said that we should drink eight glasses a day . That estimate has since been fine-tuned . Now , the consensus is that the amount of water we need to imbibe depends largely on our weight and environment . The recommendation daily varies from between 2.5 – 3.7 litres of water for men , and about 2 – 2.7 litres for women , a range that is pushed up or down if we are healthy ,active , old, or overheating . While water is the healthiest hydrator , other beverages even like with caffeine like coffee or tea , replenish fluid as well . And water within food makes up about a fifty of our daily h2o intake . fruits and vegetable like strawberries , cucumbers , and even broccoli are over 90% water , and can supplement liquid intake while providing valuable nutrients and fiber . Drinking well might also have various long term benefits . Studies have shown that optimal hydration can lower the chance of stroke , help manage diabetes , and potentially reduce the risk of certain types of cancer . No matter what , getting the right amount of liquid makes a world a difference in how you’ll feel , think , and function day to day .