<prompt> Water content is maximum inICFECFInterstitial fluidPlasma  <response>: A ICF INTRACELLULAR FLUID 23 of body water is fluid contained within cells. In a body containing 40 liters of fluid ie. about 72 kg total weight, about 25 liters is intracellular, which amounts to 62.5 58, close enough to the 23 rule of thumb. Jacksons texts states 70 of body fluid is intracellular. Extracellular fluid 13 of body water is fluid contained in areas outside of cells. For a 40 litre body, about 15 litres is extracellular, which amounts to 37.5 Again, this is close to the 13 rule of thumb cited here. Plasma 15 of extracellular fluid. Of the 15 liters of extracellular fluid, plasma volume averages 3 liters. This amounts to 20, the same as per Netters Atlas. Interstitial fluid 45 of extracellular fluid Transcellular fluid a.k.a. third space, normally ignored in calculations contained inside organs, such as the gastrointestinal, cerebrospinal, peritoneal, and ocular fluids. 