Intracellular fluid introduction
The intracellular fluid is the body fluid contained in the whole body cells. The average water content of cells is about 70%, and the intracellular fluid volume accounts for about 40% of body weight (women account for about 35% of body weight). This is because most of the intracellular fluid exists in the skeletal muscle group. Women's muscles are not as developed as men's, but they have more body fat (the fat's water content is only 10% to 30%), so women's intracellular fluid accounts for weight. The percentage is lower. The important cations in the intracellular fluid are K + (about 150mmol / L), Mg2 + (20mmol / L), and the main anions are P3- and protein.