The Elemental Diet for SIBO and IBS

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An elemental diet is a liquid diet typically used for patients who have compromised digestive systems. However, the diet is getting some new attention as a possible treatment for small intestinal bacterial overgrowth (SIBO), a theorized cause of some IBS cases.

Although it remains somewhat controversial, some research has indicated that an overgrowth of bacteria within the small intestine is responsible for IBS symptoms in some individuals. One treatment for SIBO is the use of certain antibiotics, including the medication Xifaxan. The elemental diet is being looked at as a possible alternative to antibiotics.

The Elemental Diet

The elemental diet is being looked at as a possible treatment for SIBO due to the following reasons:

  1. The nutrients in an elemental diet are believed to be completely absorbed in the very first part of the small intestine, and thus reduce the number of food components available to bacteria.
  2. Elemental diets have been shown to reduce the number of gut bacteria. Therefore it is theorized that it may be useful for clearing out bacteria from the small intestine.
  3. Researchers from the one clinical trial published to date on the subject, theorize that the elemental diet may increase the amount of bile released from the gallbladder. This effect would theoretically strengthen the small intestine's cleansing wave, thus reducing bacteria levels.
  4. These same researchers also propose that the effects of the diet on the immune cells within the lining of the intestines may also serve to eradicate small intestine bacteria.

What Does Research Say?

As mentioned above, there is only one published study on the use of the elemental diet for SIBO. The diet evaluated the effect of the diet on the level of lactulose in the breath — a measure thought to reflect the presence of excessive amounts of bacteria in the small intestine. Information was also gathered as to the effect of the diet on IBS symptoms.

In the study, 93 IBS patients who had abnormal results on the lactulose breath test (LBT) restricted their diet to an elemental diet formulation for a period of two weeks. Those who continued to show abnormal LBT results after the two weeks were advised to continue for an additional week.

After the first two weeks, normal LBT tests were seen in 80% of patients. The number increased to a total of 85% after inclusion of those who followed the diet for the additional week.

Data was more limited as to the effect of the diet on clinical symptoms, although the study reports increased improvement in IBS symptoms in patients with a normal LBT at the end of the study regardless of IBS sub-type, as compared to those who continued to show elevated LBT results.

Going on an Elemental Diet

At this point, there is only one study that addresses the use of the elemental diet for SIBO. It would be nice for there to be a nutrition-based alternative to the use of antibiotics, but as of now, the elemental diet does not seem to fit the bill. Besides being quite unpalatable, more studies need to be conducted to replicate the impressive results of this preliminary study.

However, if your IBS is quite severe, and test results indicate that SIBO is playing a role, an elemental diet might be worth putting yourself through. However, it is extremely important that any such diet is used only under medical supervision as the diet is not without risks. The diet is not to be used simultaneously with any antibiotic treatment for SIBO.

Do not be tempted to try a homemade elemental diet formulation. The elemental diet described above has been scientifically designed to provide a person with all of the nutrients that are essential for your health. You will be putting your health at grave risk should you try an alternative.

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Article Sources

  • Pimentel, M., "A 14-Day Elemental Diet Is Highly Effective in Normalizing the Lactulose Breath Test" 2004 49:73-77. Digestive Diseases and Sciences

  • Pimentel, M. "A New IBS Solution" Health Point Press 2006.
  • Russell, R. "Elemental Diets" Gut 1975 16:68-79.