Fluid compartments The question here is: How is fluid distributed within our bodies? Water makes up approximately 60% of lean body weight and is distributed both within and outside our cells. How is water compartmentalized within men and women? Label the diagram below. Extracellular fluid Intracellular fluid Interstitial fluid Total fluids Total solids Extracellular fluid Intracellular fluid Interstitial fluid Total fluids Total solids As can be seen, the majority of water (approximately 2/3) is located within our cells (intracellular fluid). The remaining fluid outside the cells (extracellular fluid; ECF) is either contained within the vascular system (plasma) or bathes the cells (interstitial fluid)