SIBO, or small intestinal bacterial overgrowth, is caused by disruption of the processes that normally control the growth of bacteria in the gut.
Treatment for SIBO depends on the reason for the bacterial overgrowth, and may involve a shift in diet, nutritional supplements, antibiotics, or surgery.
No one diet works best for everyone with SIBO, but two that may help are the low FODMAP diet and the elemental diet.
Adjusting your diet to address and ease health concerns and symptoms can be stressful. How do you know if you're eliminating or limiting the right foods? How long do you have to wait until you start feeling better? For starters, it's essential to know the underlying cause of your symptoms, so it can be addressed effectively. If you have SIBO, also known as small intestinal bacterial overgrowth, there are nutritional adjustments that could reduce your symptoms. (Source)
In this article, we'll explain what SIBO is, what causes it, what dietary changes might help you in feeling better, and how our WellTheory NTPs can support in healing your symptoms.
Gut bacteria (also known as the gut microbiome) play a vital role in the immune system — in fact, 70% of your immune system is located in your gut. Small intestinal bacterial overgrowth is the overabundance of these vital microorganisms. In the small intestine gastric acid, bile, enzymes, and immunoglobulins (antibodies) normally keep bacterial growth under control. If the function of these chemicals is disrupted, or if the movement of contents from the small intestine into the large intestine is impaired or slowed, more bacteria than normal may grow in the small intestine. This can inhibit the body's ability to absorb and digest nutrients. (Source, Source)
There are a number of potential root causes of SIBO, including:
Other conditions and factors that may also be associated with SIBO include:
Small intestinal bacterial overgrowth is often the result of a medical procedure or condition that slows down the passage of food in the digestive tract, allowing gut bacteria to collect and grow. Therefore, it's vital to understand the underlying cause of SIBO in order to treat it effectively. While SIBO has primarily been associated with patients who have motility disorders and structural issues within the GI tract, it is now thought to be much more prevalent and vastly undiagnosed. (Source, Source)
In addition to making you feel less than great, untreated SIBO can lead to a number of health problems, including:
A SIBO diagnosis is based on the symptoms presented. Common symptoms include:
It is important to note that not everyone with SIBO has symptoms, and SIBO often goes underdiagnosed in clinical settings.
Your health care provider will take a medical history, which will include questions about your diet, and conduct a physical exam, including a blood test to check for vitamin deficiencies. There are also a number of specific tests they may conduct:
Correcting the underlying cause of SIBO is of the utmost importance when it comes to treatment. The bacterial overgrowth must be managed, and damage from malnutrition and vitamin deficiency addressed.
Depending on the source of SIBO, a health care provider may opt for:
There’s no one diet that works for everyone with SIBO, and you’ll want a health care provider's guidance before starting any kind of nutrition modification. That being said, there are two diets that have been researched and shown to improve the symptoms and long-term prognosis of those with SIBO.
The elemental diet is a liquid meal replacement plan, which is usually prescribed for people with severe GI tract issues. The goal of the diet is to allow the digestive system to relax and heal while still providing needed nutrition including dietary building blocks — proteins, fats, and carbohydrates — that are easy to digest and will be absorbed thoroughly.
In addition to those with SIBO, the elemental diet is recommended for:
The elemental diet is not for weight loss, and people with blood sugar conditions such as diabetes shouldn't use it. It’s challenging to follow because solid foods are not permitted, and there can be physical side effects that may include:
In a study of 93 participants with IBS who had abnormal breath test results, 80% of those who were on the elemental diet showed an improvement in symptoms after 2 weeks. Some participants continued on the diet for another week, with 85% of participants overall seeing improvement in symptoms. (Source)
The elemental diet isn't a long-term solution, and you are meant to reintroduce foods after your digestive system has had time to rest. If you do opt for the elemental diet, your health care provider may recommend that you next move to the low FODMAP diet. (Source, Source, Source)
The low FODMAP diet is more commonly used to treat both SIBO and IBS. It's an elimination diet meant to help identify foods that may be causing symptoms. FODMAP is an acronym referring to certain carbohydrates that are poorly absorbed in the small intestine. They move intact into the large intestine, or colon, where bacterial fermentation releases excessive amounts of gas. FODMAPs may also draw large amounts of water into the GI tract, causing diarrhea.
FODMAP stands for:
Fermentable: Foods that your gut bacteria feeds on, and transform into gasses
Oligosaccharides: Carbohydrates formed from monosaccharides that act as prebiotics, feeding beneficial gut bacteria
Disaccharides: Carbohydrates formed from two monosaccharides, such as lactose, sucrose, and maltose
Monosaccharides: The most basic carbohydrates, such as fructose, glucose, and galactose
Polyols: Sugar alcohols
Like the elemental diet, the low FODMAP diet is not meant to be a long-term solution. It's an elimination diet involving three steps:
So what foods would you avoid if you were on the low FODMAP diet?
It's essential that you work with a health care provider, dietician, or nutritional therapy practitioner when embarking on the low FODMAP diet (or any restrictive diet, for that matter). Many people with SIBO also have conditions such as celiac disease, diabetes, and Crohn's, so it's important to take into consideration what these coexisting diagnoses mean when making dietary changes.
WellTheory's Nutrition Therapy Practitioners (NTPs) are trained in the low FODMAP diet, and are here to support and direct you if you opt for this particular nutritional protocol.
While there isn't one particular diet that works best for everyone with SIBO, treating SIBO is possible. Treatment for SIBO depends on the reason for the bacterial overgrowth, and may involve a shift in diet, nutritional supplements, antibiotics, or surgery. For those with moderate to severe SIBO symptoms nutritional changes, such as the elemental and low FODMAP diets, can provide some relief, but it remains essential to understand the underlying cause of SIBO.
If you have concerns about gastrointestinal symptoms, don't hesitate to consult a health care provider. It is important to note that not everyone with SIBO has symptoms, and SIBO often goes underdiagnosed.
At WellTheory, you can work with a Nutrition Therapy Practitioner and a Health Coach to not only manage your SIBO but get to the root cause of your symptoms.