Use your knowledge of Water Potential applied to the GIT to describe what can cause or prevent Constipation

Water Potential is the measure of the ability of water molecules to move freely in solution. A solution of pure water where there is no solute and all of the water molecules are free to move, the water potential is high. Intake of a soluble material such as Lactulose which lowers the water potential of the contents of the small intestines causes water to enter the lumen of the small intestines. This is because the water is drawn by osmosis moving from an area of high water potential to low water potential. The faeces are softened and less dry preventing constipationNot eating enough fibre can cause constipation or not drinking enough fluids can contribute to constipation. This is because insoluble fibre draws water into the GIT by osmosis by increasing the water potential of the lumen of the intestines. This makes the faeces larger and softer and allows for easier passage through the GIT.