The term colitis refers to an inflammation of the colon. There are several kinds, but the most common and most serious is ulcerative colitis. Once the inner wall of the colon becomes inflamed, small ulcers in the intestinal membrane can easily develop and are soon followed by fever and fatigue.
When the colon is inflamed, it has a harder time absorbing water and minerals, causing dehydration and nutritional deficiencies. Because of this poor absorption of nutrients, even light bleeding can lead to anemia.
Here again, stress, diet and food intolerances are the main causes of colitis. However, it can also stem from an autoimmune disease, an overreaction to Aspirin or the regular use of anti-inflammatories or antibiotics.