An elemental diet is a restrictive, liquid-only diet that provides the body with essential nutrients in a “predigested” form. Doctors may recommend it for people with small intestinal bacterial overgrowth (SIBO).
Healthcare professionals often prescribe an elemental diet for people with certain gastrointestinal conditions as the nutrients are more easily digestible.
While some evidence suggests using an elemental diet may benefit some people with SIBO, larger-scale clinical trials are necessary.
This article explains the elemental diet for SIBO, outlines some advantages and disadvantages, and offers tips on getting started and completing the diet.
An elemental diet is a liquid-only diet formulated to supply the body with essential nutrients in an easily digestible form.
The diet is “elemental” as it provides proteins, fats, and carbohydrates already broken down into their basic building block forms:
- amino acids
- fatty acids
Elemental diets also provide vitamins and minerals.
These predigested nutrients do not cause additional stress on the digestive tract before the body absorbs them. Healthcare professionals, such as gastroenterologists and registered dietitians, prescribe them to people with compromised digestive systems, such as those with SIBO.
Some elemental diets come as ready-to-drink beverages. Others are powdered formulas a person mixes with water. Whether the healthcare professional recommends a specific commercial brand or a prescription-only version, they will provide instructions on how to follow the diet properly.
Usually, the small intestines do not harbor much bacteria. The body has several defense mechanisms to prevent bacteria from entering the small intestines and causing issues.
However, when one or more of these mechanisms fail, bacteria can enter the small intestines and begin to multiply. This makes it more difficult to absorb nutrients and causes gastrointestinal symptoms such as:
The goal of the elemental diet is to provide a person with all the necessary nutrients in an easily digestible form while reducing the amount of food in the small intestine. The elemental diet starves the bacteria, reducing the number of bacteria in the small intestine and improving symptoms.
The scientific community seems divided on whether an elemental diet is the most effective treatment for SIBO.
In 2022, researchers with the American College of Gastroenterology (ACG) published an article regarding diet recommendations for small bowel disorders. The researchers note that while diet may modify the microbiome of the small intestine in someone with SIBO, there is greater evidence for using pharmacological treatments such as antibiotics.
Similarly, the authors of a
The authors of an older 2016 primary care review noted that SIBO symptoms improved with the elemental diet but also noted the unlikelihood of widespread use due to the diet’s restrictive nature.
In contrast, it appears there is enough
After adhering to an elemental diet for 14 days, participants underwent a follow-up breath test. Of the 93, 80% (74 people) had typical LBT. Those who still had abnormal LBT remained on the diet for an additional 7 days, after which five more participants reached typical LBT, bringing the total to 85%.
This study set the elemental diet’s standard time frame of 14–21 days.
Some potential drawbacks or challenges of the elemental diet include:
- not eating solid food for the duration of the diet
- not getting enough nutritional sustenance for a physically active daily routine
- experiencing unwanted weight loss
- feeling triggered when reintroducing solid foods, especially for people with a history of disordered eating
- not having the budget for out-of-pocket costs
Side effects of an elemental diet may include:
- mood swings
- digestive issues, such as bloating, diarrhea, and constipation
- fungal overgrowth
Someone following an elemental diet can work with a healthcare professional to monitor side effects and determine when adjustments are necessary.
Before starting an elemental diet for SIBO, a person should meet with a healthcare professional to ask questions and clarify the process.
People may wish to discuss the following topics:
- Diagnosis: It is important to have an accurate diagnosis and understand the goals of an elemental diet.
- Medications: A specialist may recommend adjusting or temporarily stopping certain medications and supplements for the duration of the diet.
- Readiness: An elemental diet can be both mentally and emotionally challenging. A person’s doctor can help prepare for those challenges and create a plan for dealing with them.
Following an elemental diet is fairly uncomplicated.
A specialist will recommend either a prescription or nonprescription formula and explain how to implement the diet properly.
Preparation depends on the specific formula. Some elemental diets come premixed in a ready-to-drink liquid, while others come as a powder to mix with water or another approved liquid.
Someone beginning an elemental diet may consider drinking each serving of the formula slowly until they become familiar with the taste, texture, and how they feel after drinking it.
An elemental diet typically lasts 14–21 days. However, the duration may vary depending on factors such as symptom severity and coexisting conditions.
Once a person completes an elemental diet, their doctor will advise them to reintroduce solid food gradually. This slow and controlled process allows the body to readjust to solid foods.
A person might find it easier to complete an elemental diet by:
- planning ahead and having enough elemental formula and all other necessary supplies ready
- staying hydrated with plenty of water
- engaging in light physical activity, such as walking or gentle yoga
- recognizing and managing their side effects right away
- getting support and encouragement from family, friends, or a support group
- keeping a journal to track progress, symptoms, and challenges
- following the food reintroduction plan
Anyone experiencing difficulty with the elemental diet can contact a healthcare professional for support, guidance, and additional resources.
An elemental diet is an all-liquid diet that supplies the body with easily digestible nutrients. Healthcare professionals may prescribe it for people with gastrointestinal conditions, such as SIBO.
The diet works by reducing food in the small intestine and starving the bacteria that cause SIBO symptoms, such as bloating and gas.
Although some evidence indicates the potential benefits of using an elemental diet for SIBO, further research is necessary.