Since toxins are not adequately eliminated by the colon it must be removed by other means. And as mentioned in the first main function above, the blood passes through the colon. From here, the blood enters the liver where it is detoxified. If the liver must perform added work, it becomes overloaded thus more toxins enter the bloodstream which can affect every cell in the body. Now the body must look for other means to eliminate the excess toxins and may choose the skin among other areas.
Water is necessary to keep the stool soft and loose to allow for easy elimination.
If we don't drink enough water, the mucous lining of the colon becomes harder and fails to provide a slick surface for waste to move. Fibre is essential for providing bulk to allow for easier movement of waste through the colon. Fibre also absorbs fats and toxins and helps eliminate them from the body. Think of it as the Liquid plumber of food. As mentioned before, friendly bacteria are essential to good health.