Symptoms like fatigue (extreme tiredness), light-headedness, and nausea can be caused by dehydration (loss of fluid from the body). To help prevent these problems, survivors should be encouraged to try to take in enough fluids. Drinking water and other liquids may also reduce the risk of bladder and colon cancer. Drinking at least 8 eight-ounce servings of liquid a day is usually advised for the general public. This is reasonable advice for survivors, too, with the exception of those who have a specific medical reason for restricting fluid intake.