Elemental Diet For SIBO In 2023 | Pros & Cons And Side Effects

 Everything To Know About Elemental Diet For SIBO 

For a long time, researchers and clinicians treating individuals with gastrointestinal diseases believed that good therapeutic responses were only possible if the bowel was completely at rest.

This meant that most patients were only able to gain necessary nutrients through intravenous feeding, which often meant longer hospital stays that still did not completely resolve these gastrointestinal problems.

As a result, physicians began to investigate how a diet consisting of foods that were already in their “pre-digested” state may improve patient outcomes while also giving them a greater quality of life in the process.

The elemental diet was originally developed in the 1970s for a couple of reasons:

  1. By a group of physicians investigating how breaking down certain proteins could improve both human and animal intestinal health. 1
  2. For use in space exploration by astronauts on prolonged journeys where the problems of storage, ingestion, and waste disposal were important. 2

Basically, it has been shown that the elemental diet is one of the most effective treatment options for patients suffering from a variety of digestive conditions, particularly those struggling with small intestinal bacterial overgrowth SIBO symptoms. 3

In this article, we will detail everything you need to know about the elemental diet so that you can decide if this treatment approach is right for you. As you will see, using the elemental diet for SIBO treatment, inflammatory bowel disease, and other digestive issues is very effective.

What is an Elemental Diet?

elemental diet powder

Very simply, the elemental diet is a liquid formula (usually in powdered form) that contains all the essential nutrients humans need to live broken down into their simplest forms so they are easily absorbed.

Types of Nutrients Included:

  • Carbohydrates in the form of monosaccharides
  • Proteins in the form of amino acids
  • Fats in the form of fatty acids
  • Essential vitamins and minerals

By eliminating the need for the GI systems of these patients to perform normal digestive functions, as well as limiting the fuel source for bacteria, the elemental diet acts as a protective way to ensure that patients still consume all the necessary nutrients during this treatment period while allowing the bowels to rest and decreasing bacterial overgrowth.

The main mechanisms by which the elemental diet helps a damaged GI system include:

  • Enable passive absorption of nutrients
  • Little to no stimulation of biliary and pancreatic secretions
    • Decreasing the activity of these enzymes prevents the ability of potentially painful endogenous (naturally occurring) agents present in the GI tract to release
    • Reduced load of potentially allergic components in food products
    • Improved nutrition consumption, particularly if a patient appears to be deficient in certain elements/vitamins
  • Reduce GI bacterial flora populations

To achieve these physiological benefits, the main components of an elemental diet must include:

  • FATS – in the form of an oil (soybean, coconut, olive, etc.)
  • PROTEINS – in the amino acid form (or peptide chain form)
  • CARBOHYDRATES – NOT in the form of long-chain and complex carbohydrates (dextrose, glucose, and/or maltodextrin)

An elemental diet is recommended for individuals, typically with SIBO, IBS, IBD, and other GI disorders, who experience the following symptoms:

  • Very high gas levels
  • Inflammation or a damaged gut
  • Methane positive breath test (this can be a more difficult type of IBS to treat)
  • Herbal medication sensitivity
  • Pharmaceutical medication sensitivity
  • Highly restricted diet
  • SIBO has appeared to be resistant to other treatments and/or antibiotics
  • Patient prefers a natural treatment option

Using The Elemental Diet for SIBO

using elemental diet for sibo

As a result of an alteration in the type and/or a number of bacteria present within the small intestine, patients with small intestinal bacterial overgrowth (SIBO) often experience a wide variety of GI symptoms including bloating, abdominal pain, diarrhea, constipation, gas, cramping and more.

As one of the most promising treatment options for patients with both moderate to severe SIBO, the elemental diet is a life-altering tool that has helped many patients reduce bacterial overgrowth and re-establish a more normal gut.

Compared to using antibiotics for SIBO treatment the elemental diet has been shown to be even more effective. Patients who were prescribed Xifaxan had a success rate of approximately 64%, while patients who underwent a 2-week elemental diet had a success rate of 80-85% in eradicating SIBO.

The success of the elemental diet for patients with SIBO is primarily attributed to the pre-digested state of the nutrients which are quickly absorbed, preventing the surplus of bacterial species from feeding on carbohydrates.

By starving bacteria in this area, an elemental diet is an effective tool in reducing bacterial overgrowth in the small bowel 4.

If using the elemental diet for SIBO, it’s recommended that you use it for at least 2 weeks if not longer to see results. This allows the bowel rest and enough time to reduce bacterial overgrowth in the small intestine.

Full Elemental Diet vs. Semi-Elemental Diet

full vs semi elemental diet

So what’s the difference between a “full” elemental diet and a “semi” elemental diet?

In terms of the elemental product formulations, the main difference is usually in the protein structure. For example, a “full” elemental formula is usually just composed of free-form amino acids while a “semi” elemental formula has longer chains of amino acids or protein peptides like whey isolate.

In terms of the elemental diet treatment process, a “half” elemental diet could also be when someone uses an elemental formula like Absorb Plus or Vivonex Plus and combines that with real foods using the elemental formula as a supplement for a certain amount of meals or extra nutrition.

Various scientific studies have found that patients with GI disorders show a beneficial response when their normal diet is supplemented with elemental formulations. In fact, these studies show that a full elemental diet may actually suppress the patient’s diet and ultimately reduce their ability or interest in consuming normal foods following the completion of their elemental diet regimen.

Overall, it has been shown that “semi” elemental diets are just as effective if not more effective in patients as compared to full elemental diets.

Studies Supporting the Full Elemental Diet

The elemental diet has become an increasingly popular treatment option recommended by physicians as clinical research has continued to demonstrate the efficacy of this treatment option for SIBO, as well as a variety of other GI disturbances 5.

Below are some of these studies and the results of patients’ health following completion of the “full” elemental diet.

Table 1: Collection of clinical research studies supporting the elemental diet for treating a variety of GI disorders.

Test changes in intestinal microbiota of Crohn’s patients on the ED
  • Lower level of bacterial species present in fecal samples
Shiga et al. (2012)
Comparison of elemental and empiric elimination diets for the treatment of eosinophilic esophagitis (EoE) (chronic immune-mediated disorder of the esophagus)
  • Elemental diet with amino acid-based formula is most effective in maintaining remission of EoE; however, poor compliance rates are associated with elemental formulations that taste bad
Warners, et al. (2015)Markowitz et al. (2003)
Improving GI symptoms following radiation treatments for pelvic cancers
  • The different types of elemental formulations did not affect the patients’ compliance in this study
  • Improved calorie and nutritional intake
McGough et al. (2006)
Both long term and short-term use of the elemental diet to manage Crohn’s Disease
  • Severity of disease reduced
  • Reduces strictures, fistula and perianal disease rates in patients
Teahon et al. (1990)
Treatment of IBS/SIBO patients with abnormal lactulose breath test (LBT) rates
  • 2-week elemental diet duration
  • Vivonex Plus used
  • Normalized LBT levels found in patients at both 15 and 21 days following when patients began the elemental diet
  • Improved bowel symptoms associated with improved breath test rates
Pimental et al. (2004)

Studies Supporting the Semi-Elemental Diet

It is important to note that the “full” elemental diet will only contain protein sources in their free amino acid form, carbohydrates in their simplest form of oligosaccharides or monosaccharides, and fats as medium-chain triglycerides (MCT).

On the contrary, the semi-elemental diet instead can contain protein in the form of peptides of varying chain length, carbohydrates in the form of simple sugars, glucose polymers, and/or starch and fats as MCTs.

One of the biggest advantages associated with the semi-elemental diet in comparison to the full elemental diet is attributed to the different protein forms used in these two diets.

While the free amino acid forms used in the full elemental diet prevent the patient from experiencing any type of allergic reaction to the protein component of the formulation, this form of protein does not prove to be effective in improving weight gain and/or malnutrition issues.

In fact, research has shown that free-form amino acids cannot help build muscle for patients unless they piggyback on a dipeptide (or higher) protein bond 6, such as that which can be found when consuming whey isolate, for example.

To learn more about this process, see this paper.

Basically, a high-quality semi-elemental diet formula or semi-elemental diet that includes a little bit of food can be even better than a full elemental formula.

Table 2: Collection of clinical research studies supporting the semi-elemental diet for treating a variety of GI disorders.

Compare a full elemental diet (enteral feeding) with a semi-elemental diet (amino acid-based feed combined with a whole protein-based diet) in Crohn’s patients
  • Similar benefits were shown for patients on the full elemental diet as compared to those on the semi-elemental diet
  • Serum C reactive protein concentration levels were improved in patients on both diet regimens
  • Conclusion: Semi-elemental diets can be just as effective in treating Crohn’s patients as elemental diets
Raouf et al. (1991)
Investigate the nutritional and health benefits associated with a semi-elemental diet
  • Semi-elemental diet has proven beneficial for patients in “high-risk” categories, such as those with Crohn’s disease, short bowel syndrome, etc.
  • Semi-elemental diet has proven to perform just as well or better than full elemental diets in terms of tolerance, digestion and nutrient assimilation for patients with a wide variety of disease conditions
Alexander et al. (2016)
Investigate how a semi-elemental diet vs. a full elemental diet (using Vivonex-TEN) improves outcomes of adults with moderate to severely active Crohn’s Disease
  • Greater remission rates after 1 year in patients on a semi-elemental diet as compared to a full elemental diet
  • Increase weight gain after 1 year in patients on a semi-elemental diet as compared to a full elemental diet
Royall et al. (1994)


Expert Advice Using The Elemental Diet

I had a chance to sit down with Jini Patel to discuss the elemental diet and her experience working with people around the world to heal their guts naturally.

Pros and Cons of the Elemental Diet

pros and cons of elemental diet

So, you’re thinking of using the elemental diet for SIBO or another gut illness. These are the pros and cons you should consider.


  • 80-84% success rate
  • Easy to order formulations online
  • Can dramatically reduce gas levels and symptoms in a 2-3 week course
  • Can reduce the need for antibiotics and their side effects
  • Allows the patient to take a break from preparing meals


  • Products can be expensive as the treatment course continues
  • Not allowed to eat food for 14 days
  • Die-Off Symptoms can be severe
  • Some people don’t like the taste

When is the Elemental Diet Recommended?

when elemental diet is recommended

A physician may recommend an elemental diet for a variety of medical purposes, some of which include:

  • Postoperative Management
    • Nutritional support
    • Particularly useful in healing patients following colonic and rectal surgeries, as well as neonatal and pediatric surgeries where adequate nutrition may be difficult to achieve following surgery
  • Preoperative preparation
  • Management of GI fistulae following procedures
    • Associated with reducing mortality rates
    • Balances nitrogen, potassium, and magnesium levels in patients while on the diet
    • Improved serum protein levels
  • Management of malabsorption and maldigestion states
  • Short bowel syndrome management
    • Improved symptoms
    • Reduced diarrhea, constipation, gas, bloating
  • Nutritional management during cancer treatments
    • Protection against weight loss
    • Reduced rectal lesions during chemotherapy
    • Protects against radiation damage that can affect small intestinal mucosa
  • Liver disease and failure 7

When is the Elemental Diet Not Recommended?

when elemental diet not recommended

  • History of eating disorders
  • Low body mass index (BMI), underweight patients
    • Note that the elemental diet has been associated with increased body weight for individuals with malabsorption issues so this may not be an issue
  • Diabetic patients
    • Higher sugar content of the elemental diet
  • Intestinal fungal overgrowth
    • Can be used for these individuals if they are also prescribed an antifungal agent

Potential Side Effects of the Elemental Diet

elemental diet side effects

It’s not uncommon for individuals on the elemental diet to experience a variety of side effects, mostly due to the ingredients in the formula or the “die-off” reaction to a changing microbial environment.

Some common symptoms that should not alarm an individual on the elemental diet include:

  • Feelings of constipation
    • Maybe a result of decreased bowel movement due to decreased fiber
    • Does not necessarily mean it is abnormal
    • Most nutrients are being completely absorbed before food enters the colon
    • Can be treated with magnesium, suppositories, enemas, herbal laxatives, etc.
  • Nausea
    • Can occur if the elemental diet is ingested too quickly. Sip slowly
    • Usually begins in the first few days
    • Will typically resolve itself if the formula is diluted
    • Can also occur if a patient is also taking vitamins/supplements when on the ED
  • Diarrhea
    • Maybe a result of an ingredient in the formula that the patient is sensitive to or a die-off reaction
    • Recommended that patients increase water intake and relax
  • Feeling lightheaded
  • Symptom aggravation
  • Abdominal cramps
  • Body aches
  • Fatigue
  • Blood sugar dysregulation

Elemental Diet Dosage

elemental diet dosage

One of the most important aspects of the elemental diet is ensuring that you are consuming a sufficient amount of calories each day throughout the duration of your elemental diet.

This is particularly important for individuals who are interested in maintaining their weight during this time.

If you are using just elemental shakes on your diet then you need to make sure to get the recommended amount of calories for your body weight. Be sure to use an online nutrition calculator to figure out how many calories you need, then order the correct amount of product for the duration of your treatment.

Elemental Diet Product Options

Currently, there are a few main elemental formulas on the market. Check out the table below to compare the main elemental formula options.

Comparison of Main Elemental Formulas:

Absorb Plus #1 Whey Isolate Tapioca Maltodextrin No fat included, add your own SEE PRODUCT
Physicians Elemental #2 Free Form Amino Acids Dextrose & Tapioca Maltodextrin Medium Chain Triglycerides SEE PRODUCT
Vivonex Plus #3 Free Form Amino Acids Corn Maltodextrin Soybean oil SEE PRODUCT

Absorb Plus

absorb plus elemental diet

Absorb Plus is a high-quality elemental formula and one of the best.

Some consider it a “semi” elemental formula due to the whey protein isolate but this allows you to pack on muscle and maintain weight more effectively. The product tastes good and has been used successfully by many people with IBD and IBS.

Especially good for:

  • Maintaining weight and adding muscle
  • People looking to order online
  • Anyone who is sensitive to fat and wants to adjust their intake

Physicians Elemental Diet

physicians elemental diet

The Physicians Elemental diet is another high-quality elemental formula. It is a “full” elemental formula because it contains protein in the form of free-form amino acids. This product tastes excellent as well and many people have used it successfully.

A physician is required to order the product.

Especially good for:

  • Someone who needs to use a free form amino acid formula or cannot tolerate other proteins
  • Someone who is having a doctor orders their product for them

Vivonex Plus

Vivonex Plus Unflavored 2.8 oz. Individual Packet Powder, 07129800 - Case of 36

Buy on Amazon

Vivonex Plus is a full elemental diet product that contains free-form amino acids and corn maltodextrin as the carb source. The ingredients in this formula are low quality and it tastes nasty. Many people have had successful results using the formula but it is very difficult to get down due to the horrible taste.

Recommended Elemental Formula

In summary, we recommend using Absorb Plus because of the quality of ingredients, taste, and protein structure which will enable you to put on muscle and maintain weight while on the elemental formula. With Absorb Plus you can also control the amount of fat depending on your body’s tolerance and requirement.


Homemade Elemental Diet

A patient may be interested in creating their own elemental diet formulations for a variety of reasons.

Some patients have found that a homemade elemental diet was better for them because they could customize the ingredients used and switch up the carbohydrate and fat ratios. You can also save a little bit of money taking the DIY route.

But, this method usually takes more research, time, and commitment to figure out the exact specifications.

If you are interested in preparing your elemental formulations at home, here is a recipe that can help you get started:

“Homemade Elemental Diet” – Dr. Allison Siebecker

You Just Finished the Elemental Diet – Now What?


Most often it’s recommended that patients who have successfully completed the elemental diet slowly transition back to actual foods by beginning with broths and a low FODMAP diet over the course of a week. Additionally, it may be beneficial to continue to supplement with elemental formulations during this transition period.

It is also highly recommended, particularly for patients with SIBO, that immediately after completing the elemental diet that they begin to take a prokinetic supplement to help stimulate the migrating motor complex which helps prevent the re-growth of unwanted bacterial populations.


In conclusion, the elemental diet is a great way for patients struggling with GI issues, nutrient absorption, or a wide variety of other health issues to absorb important nutrients through their diet!

The benefits associated with both full elemental and semi-elemental diets are well documented. While there are some formulations such as Vivonex Plus, which are hard to tolerate, there are a couple of other products available, such as Absorb Plus, that can help make this diet a little easier on your taste buds.

With over an 85% success rate, particularly in patients with SIBO, the elemental diet is a clearly valid and highly recommended treatment option that may help you.

Still not sure which treatment is best for you? Learn more about the different treatment options for SIBO. Also don’t forget to checkout out SIBO Survivor Cookbook to explore our vast collection of tasty, gut-friendly, and easy to prepare recipes.

  1. Read more about SIBO diet here


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