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Colon tests are physical examinations of the colon for purposes of identifying the presence of unusual growths. As the colon is the body part that receives waste material from the small intestine before it is passed out, it is important to know what food may or may not be eaten before and during the tests to ensure result reliability.

Colon Tests

Fecal occult blood test (FOBT) is a stool test that can be done at home. The stool specimen is taken and then sent to the laboratory for testing. This test aims to detect the presence of occult blood in the stool. Occult blood may be an indication of colorectal disorder.

Colonoscopy is an examination involving the rectal insertion of a flexible tube with a camera at its end. This is the most commonly used procedure for colon testing.

Sigmoidoscopy is almost the same as colonoscopy except that it does not cover the entire length of the large intestine. It can reach only up to the lower part called the sigmoid.

Barium enema is a relatively safe procedure involving a rectal injection of barium to coat the colon lining. This is followed by an x-ray track of the liquid.

Combination Tests

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It is common for FOBT and any one of the other tests to be done in combination. If a colonoscopy or other similar tests are to be performed, it is important that a certain strict diet be imposed prior to testing to make sure that the inside of the colon is clear of unwanted substance or obstructive waste matter that may be a reason for a misreading.

Foods to Avoid

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Doctors recommend the following food intake procedure four days before a colon test. Stop eating fiber and fiber supplements. You should limit coffee, alcohol and chocolate consumption. Stop taking colon-cleansing products. Avoid eating rice, red meat, vegetables, nuts and seeds as well as taking red drinks and other drinks with artificial color. Avoid milk and dairy, whole-grain pasta, fruits such as cauliflower, broccoli, turnips, radishes, and cantaloupe. Do not take aspirin or other similar non-steroidal drugs or iron supplements and Vitamin C above 250 mg.

One day before the procedure, the following food abstention should be observed: no coffee. Coffee may cause gastritis or stomach upset. Stay away from laxatives. Nothing else should be taken by mouth three hours before the actual tests.

The purpose of this food abstention is to regulate the intake of food that will be ingested, making sure that no adverse chemical reaction of foods eaten takes place in the colon. At the same time, it is expected that the food ingested will be soluble enough to expel all the waste material it holds before colonoscopy is performed.