There are issues with accurately diagnosing SIBO.
The most reliable test is to measure the amount of bacteria found in a sample of fluid which is taken from the small intestine (the jejunum to be specific). Unfortunately this test is invasive so it isn’t commonly used as a way of diagnosis (2).
Hydrogen and methane breath tests are more commonly used to diagnose SIBO. These tests work by measuring the amount of hydrogen and/or methane produced after consuming a solution which contains either lactulose or glucose.
However, breath tests are less accurate than testing jejunal fluid and carry a risk of both false positive and false negative results depending on how long digestion takes (gut transit time) (3 – 4).
There are a variety of treatment options available for SIBO, however these vary in terms of reliability. This is also a new area of research, so more studies are needed to investigate these.
The most established treatment for SIBO is a course of antibiotics such as: rifaximin, metronidazole or ciprofloxacin (5).
Probiotics may be a useful in the management of SIBO, but the studies which have investigated this have found mixed results so far (6-7).
A number of changes to the diet have been linked with improving the symptoms of SIBO, but the research into these diets is new and more investigation is needed overall.
An elemental diet may help to reduce the number of harmful bacteria in the small intestine for those with SIBO (7). This diet involves consuming all food in liquid form using specialized supplements which contain protein, carbohydrates and fats which are broken down to their simplest forms.
An elemental diet is a very specific and restrictive diet which requires the use of specific prescribed supplements along with support from a specialist dietitian.
There is some evidence that the low FODMAP diet may help to reduce the risk of SIBO returning after it has been treated with antibiotics (1). See here for more information about the low FODMAP diet. However, this is a short term intervention and carries its own considerations.
The ‘specific carbohydrate diet’ and the GAPS diet are sometimes promoted as a treatment options for SIBO. However, both of these diets are very restrictive and there isn’t good evidence for using either of these in the treatment of SIBO.
It is important not to self-diagnose and follow strict diets, but to seek support from your doctor in order to find the best treatment options for you.
where to find support: