Some chronic low intensity nausea can occur for a protracted time due to sustained low-level food allergies or problems with food combinations. Patients with lower-level nausea usually have their symptoms disappear with diet revision. Bloating can result from excessive gas in the digestive system, failure of the digestive tract to sustain youthful peristaltic contractions, or a lack of sufficient quantities of digestive enzymes and bile acids required to rapidly break down food. Intestinal gas results from food fermentation and from swallowing air while eating. The bloating from intestinal gas is different from that which occurs in the colon.
Constipation is the decreased frequency or slowing of peristalsis resulting in harder stools.
When the gastrointestinal tract is slowed down, feces can accumulate in the colon with attending pain and toxic reactions. Some patients experience painful days of constipation followed by forceful diarrhea and watery stool, often accompanied with abdominal cramps. Diarrhea is the increased frequency of bowel movement that is also loose or watery. If diarrhea increases, the possibility of celiac disease is considered. Celiac disease is a serious disease that allows certain macromolecules to pass through the intestinal wall.