Gastrointestinal diseases affect the gastrointestinal (GI) tract from the mouth to the anus. There are two types: functional and structural. Some examples include nausea/vomiting, food poisoning, lactose intolerance and diarrhea. Functional diseases are those in which the GI tract looks normal when examined, but doesn't move properly. They are the most common problems affecting the GI tract (including the colon and rectum). Constipation, irritable bowel syndrome (IBS), nausea, food poisoning, gas, bloating, GERD and diarrhea are common examples.

Many factors may upset your GI tract and its motility (ability to keep moving), including:

• Eating a diet low in fiber.
• Not getting enough exercise.
• Traveling or other changes in routine.
• Eating large amounts of dairy products.
• Stress.
• Resisting the urge to have a bowel movement, possibly because of hemorrhoids.
• Overusing anti-diarrheal medications that, over time, weaken the bowel muscle movements called motility.
• Taking antacid medicines containing calcium or aluminum.
• Taking certain medicines (especially antidepressants, iron pills and strong pain medicines such as narcotics).
• Pregnancy.

What are structural gastrointestinal diseases?

Structural gastrointestinal diseases are those where your bowel looks abnormal upon examination and also doesn't work properly. Sometimes, the structural abnormality needs to be removed surgically. Common examples of structural GI diseases include strictures, stenosis, hemorrhoids, diverticular disease, colon polyps, colon cancer and inflammatory bowel disease.

Constipation

Constipation, which is a functional problem, makes it hard for you to have a bowel movement (or pass stools), the stools are infrequent (less than three times a week), or incomplete. Constipation is usually caused by inadequate "roughage" or fiber in your diet, or a disruption of your regular routine or diet.

Constipation causes you to strain during a bowel movement. It may cause small, hard stools and sometimes anal problems such as fissures and hemorrhoids. Constipation is rarely the sign that you have a more serious medical condition.

You can treat your constipation by:

• Increasing the amount of fiber and water to your diet.
• Exercising regularly and increasing the intensity of your exercises as tolerated.
• Moving your bowels when you have the urge (resisting the urge causes constipation).

If these treatment methods don't work, laxatives can be added. Note that you should make sure you are up to date with your colon cancer screening. Always follow the instructions on the laxative medicine, as well as the advice of your healthcare provider.

Irritable bowel syndrome (IBS)

Irritable bowel syndrome (also called spastic colon, irritable colon, IBS, or nervous stomach) is a functional condition where your colon muscle contracts more or less often than “normal.” Certain foods, medicines and emotional stress are some factors that can trigger IBS.

Symptoms of IBS include:

• Abdominal pain and cramps.
• Excess gas.
• Bloating.
• Change in bowel habits such as harder, looser, or more urgent stools than normal.
• Alternating constipation and diarrhea.

Treatment includes:

• Avoiding excessive caffeine.
• Increasing fiber in your diet.
• Monitoring which foods trigger your IBS (and avoiding these foods).
• Minimizing stress or learning different ways to cope with stress.
• Taking medicines as prescribed by your healthcare provider.
• Avoiding dehydration, and hydrating well throughout the day.
• Getting high quality rest/sleep.