Final answer:
The percentage of body weight attributed to water varies by age, ranging from 75% in infants to 45-60% in adults. The highest water content is observed in the brain and kidneys, while teeth have the lowest. Adequate daily water intake is vital for maintaining proper body function.
Step-by-step explanation:
The percentage of body weight attributed to water varies based on several factors, including age and body composition. In infants, water comprises about 75 percent of body mass, while in adults, it accounts for about 50-60 percent. For older adults, this percentage can decrease to approximately 45 percent. Notably, the brain and kidneys are composed of 80-85 percent water, making them the organs with the highest water content. On the other hand, teeth present the lowest water content at 8-10 percent. Water distribution in the body is key for a variety of functions, acting as a lubricant, aiding in digestion, circulation, and body temperature regulation, and it also participates significantly in cellular processes, such as osmosis.
As adults, the percentage of body water can be as high as 70 percent, which includes water within our cells (intracellular fluid) as well as the water between our tissue cells (interstitial fluid) and blood plasma (extracellular fluids). It is essential for the myriad reactions that occur within our cells, and also plays a crucial role in the movement of substances through semi-permeable membranes.
Considering daily water loss from the body via urination, perspiration, and respiration, it is frequently recommended to ingest about five or more 16-ounce glasses of water daily to maintain hydration and overall health.