Bloating, Gas, IBS, Diarrhoea or Constipation?

It could be Sibo – a chronic and often misunderstood condition that occurs in the gut and affects millions of people. The only way to find out if you have this condition is with a SIBO breath test.

What is SIBO?

SIBO (Small Intestine Bacterial Overgrowth) is a condition in the small intestine where good or bad bacteria begin to congregate in far higher numbers than normal. The bacteria cause a wide variety of uncomfortable and often embarrassing symptoms for millions of SIBO sufferers. Symptoms of SIBO can affect much more than just digestion so sadly it is often missed as a possible cause of some health problems. The only way to currently diagnose this condition is by taking a SIBO breath test – a simple to use, DIY home test kit.

Did you know?


Cases of IBS that are actually SIBO


People with SIBO that have leaky gut


People with fibromyalgia that have SIBO

Signs of SIBO

SIBO affects people in many different ways – Digestion is most commonly affected with bloating, constipation and or diarrhoea being typical but it is a complicated condition and it can cause a very broad array of symptoms. Often missed as a contributory factor SIBO can play a part in Chronic Fatigue (CFS), roseacea, restless legs, cystitis,  prostate issues and many more health concerns.

Symptoms of SIBO

  • Diarrhoea – Usually associated with hydrogen dominant SIBO
  • Constipation – usually associated with methane dominant SIBO
  • Alternating constipation and diarrhoea
  • Gas
  • Flatulence
  • Belching
  • Severe Bloating
  • Abdominal pain and cramps
  • Leaky gut  – Intestinal permeability
  • Malabsorption which can lead to Steatorrhea (Fatty Stool) or anaemia
  • Chronic pancreatitis
  • Lactose intolerance
  • Fructose intolerance
  • Sucrose intolerance
  • Iron and B12 deficiency
  • Fatigue
  • Nausea
  • Acid Reflux
  • Gerd (Gastro oesophageal reflux disease)
  • Acne rosacea
  • Skin rashes
  • Restless legs
  • Joint pain
  • Weight loss or gain
  • Food sensitivities
  • Incontinence
  • Headache
  • Interestitial cystitis
  • Rheumatoid arthritis
  • Chronic Fatigue sydrome
  • Fibromyalgia

What causes SIBO?

Research shows the main cause of SIBO is a reduction or slowing of motility (the movement of food) through the gut, this impacts on the levels of bacteria present in the small intestines. Think of a stagnant pond where bacteria flourish and grow in large unwanted amounts opposed to a clean free flowing stream which keeps bacteria levels as they should be.

There are two main causes of slowed motility in the gut.

1. The cleansing sweeping action  ‘Migrating Motor Complex’ MMC in the gut stops working properly. The MMC makes cleansing sweeping like motions between meals that ‘clean’ the small intestine. The sweeping motion should move undigested food and excess bacteria towards the large intestines.  When the MMC is faulty undigested food becomes food for the bacteria causing or exacerbating SIBO. The major cause of malfunctioning MMC is food poisioning.

2. Structural changes which affect the motility of the gut can also cause SIBO. Some diseases, medical conditions and procedures can cause these structural changes. For example; scarring after operations,  Inflammatory bowel disease, diverticulosis, blind loops, radiation damage, stricture, fistulas, intestinal pseudoobstruction and adhesions resulting from surgery are all known to impact on or cause SIBO.

Contributory and risk factors that can affect SIBO

  • Low stomach acid – hypochlorhydria
  • Drug-induced hypoacidity (Low stomach acid) – This is commonly seen on those that take PPI’s Proton pump inhibitors PPI’s
  • Inflammatory bowel disease
  • Chronic alcohol use
  • Celiac disease
  • Chronic pancreatic insufficiency
  • Lactose intolerance – lactose is the type of natural sugar that you find in dairy products.
  • Damaged ileocecal valve
  • Immunodeficiency (especially of secretory immunoglobulin A)

How to treat SIBO

World leaders in the battle against SIBO have been treating and researching SIBO for many years now and have found there are 3 main ways to address SIBO:

1. Antibiotics

The antibiotic Rifaxamin is considered the number 1 antibiotic choice for hydrogen or Methane dominant SIBO and is often combined with neomycin. 

Rifaxamin isn’t licensed for use against SIBO in the UK however some people do manage to get a prescription from either their GP or gastrointestinal consultant. The IBS and SIBO clinic practitioners work closely with a private GP who is happy to prescribe Rifaxamin when suitable.

2. Antimicrobials

A  range of different natural plant based antimicrobials have been found to be as effective against SIBO as the antibiotics and these can also impact on SIFO (small intestine fungal overgrowth).

As the choice of antimicrobial is very dependant on the type of SIBO you have; hydrogen, methane or hydrogen sulphide,  we recommend working with a knowledgable SIBO practitioner  to ensure your programme is effective.

3. Elemental Diet

The elemental diet involves consuming a predigested drink that provides all of your daily nutrient needs but doesn’t feed the bacteria.

Studies show the elemental diet  helps to eradicate SIBO in 85% of people.

Many people shy away from this as they worry about weight loss and energy but if it is done correctly, with a practitioner if possible, this shouldn’t be an issue and shoudn’t be ruled out as it can be a very successful SIBO treatment.


There are also a number of different diets that can be used to help manage the symptoms of SIBO.

Diet alone will not eradicate SIBO.  Dietary changes can however support an antimicrobial programme and can help to make you more comfortable by relieving some symptoms.

The most common diets that are followed are the SIBO specific diet, The  FODMAP diet, SCD, Bi-Phasic diet and the Cedar’s Sinai Diet. The suitability of one diet for one person and another for someone else be very confusing.

The individual suitablity of one diet over another is thought to be due to the type of bacteria causing the overgrowth.


If you need help with a SIBO treatment plan we are happy to refer you to

The dedicated team at IBS and SIBO clinics have years of experience dealing with SIBO, IBS (Irritable bowel syndrome),  IBD (Inflammatory bowel disease) and other complicated digestive issues.  The practitioners attend all of the yearly world SIBO symposiums and keep up to date with the latest research. The founder Emma Wells is a nutritional therapist with over 18 years experience. Emma lectured on digestion and digestive testing for over 10 years and is studying to be a functional medicine practitioner. Emma also has regular one on one mentoring sessions with Dr. Alison Siebecker ND  – A top world class SIBO practitioner and educator. also work with and refer people to a knowledgeable and experienced private doctor should you be one of their patients and need a private prescription for antibiotic treatment.

Order a SIBO breath test

There are two types of SIBO breath tests available.

The Standard breath test and the Glucose breath test.

We tend to favour the Lactulose breath test as do most world SIBO experts. Lactulose is a non absorbable sugar and is often confused for lactose the type of sugar you find in dairy produce – this makes lactulose dairy free. Lactulose passes through the whole of the small intestines enabling it to pick up SIBO in the early and latter parts of the small intestines.

The Glucose breath test is slightly more accurate but glucose is absorbed higher up in the early part of the small intestines and therefore can miss SIBO if the overgrowth is further along the small intestines.

Frequently Asked Questions

General Questions

Who are Smart Nutrition?
Smart Nutrition Ltd are the company that are providing you with your Smart SIBO Breath test. Smart SIBO test will show up on your order confirmation emails but Smart Nutrition Ltd will show up on your paypal receipt. Smart Nutrition Ltd was founded many years ago to offer a trustworthy health testing service to people with a range of health concerns. Smart Nutrition Ltd and Smart SIBO test use only fully accredited laboratories to assure you can trust your results.

Who is Emma Wells?
Emma Wells Dip ION, NTC, CNHC, mBANT is a fully qualified Nutritional therapist with over 14 years experience. Emma has lectured widely in many subjects including digestion and digestive testing and she keeps up to date by researching Nutrition and SIBO related news as well as attending twice yearly SIBO conferences. Emma is also studying to be a functional medicine practitioner. Emma Wells works as a consultant to Smart Nutrition Ltd.

How long do the results for the Smart SIBO test take?
The turnaround for the test is 10 working days. We do however aim to get results out sooner than this where ever possible.

How long can I take to do the Smart SIBO test? 
You need to complete the test in 4 months from the date of you order.

I don’t feel confident doing the test on my own. Is there somewhere I can go to get it professionally done?
Yes. Whilst many people find they are easily able to carry out the test at home we can arrange for you to have the Smart Sibo test done at a laboratory in Central London UK. There is a further charge of £35.00 for doing the test at the lab. You will find an option at the checkout for you to be able to add this to your order. As soon as we get your order we will share the lab details with you so that you can arrange a suitable time with the lab for you to go in and complete the test.

Do you ship to countries outside of the UK?
Yes. We are happy to ship the test kits all over the world. If your country isn’t covered when you get to the checkout please do get in touch with [email protected] and we will be happy to help.  Posting the kit out to some locations will include an extra postage fee.

How long does it take to actually do the Smart SIBO test?
The Smart SIBO test takes 3 hours to complete but you wil need to follow a prep diet for 1 day before or, if constipated 2 days before the test.

I am doing both tests – Can I do the Lactulose and the Glucose breath test at the same time?
To ensure accuracy of the test results the tests need to be done on separate days. Please follow the prep diet and fast as instructed and complete test no 1. Please then continue with the prep diet and fast over night and collect the breath samples for test 2.

Will you explain what my results mean?
Yes,  We send an email with your results and we explain what your results mean – Whether they are hydrogen or methane positive or negative or if your results are looking like a possible hydrogen sulphide type of SIBO.  We include a supporting document which explains how the test is interpreted which you can share with your health care provider if you wish.

What shall I do if my results are positive can you help?
Should your results be positive we would be very happy to refer you to where their highly trained and experienced practitioners are able to help you.  They offer Skype appointments as well as in person appointments meaning they can see people all over the world.

If my results are positive is the programme to get rid of SIBO included in the cost of the test?
Unfortunately not. The cost of the Smart SIBO test covers the cost of the test only. You would need to contact your doctor or health practitioner for treatment or we are happy to refer you to who will be happy to help you.

Will the SIBO breath test be able to tell if I have SIFO (Small Intestine fungal overgrowth)?
Unfortunately not. You can do a simple urine test or a stool test that tests for the presence of fungal overgrowth but these tests cannot determine where in the digestive tract the overgrowth may be. If you are concerned about this or if you are interested in a test for fungal overgrowth then please do get in touch as we would be happy to discuss this with you. [email protected]

Can my child do the Smart SIBO Breath test?
As long as your child is over 50Lbs and is able to blow into a tube then yes. If your child weighs less then please get in touch as we will need to adjust how much lactulose or glucose is used during the test

Test Preparation; Diet, Supplements and Medication

I have a lactose intolerance and want to do the Smart SIBO test. Will this be a problem?
No this won’t be a problem. Lactulose (not lactose) is consumed at the start of the test and is a mixture of galactose and fructose.

Do I need to follow any special dietary requirements for the test?
Yes, You will need to follow a special low fermentation diet for 1 day before the test or if constipated for 2 days. The Instructions include full details about the diet including meal ideas.

I am on a FODMAP diet and want to do the test – will it affect my results?
Being on the FODMAP diet will not affect your results unless you have been on the diet for more than 10 months.

I have just finished a course of antibiotics – Can I still do the Smart SIBO test?
You need a break of two weeks after antibiotics before you can do the Smart SIBO test.

I have just finished a course of natural plant based antimicrobials – Can I still do the Smart SIBO test?
You need a break of two weeks after a course of natural antimicrobials before you can do the Smart SIBO test.

I take probiotics – Can I still do the Smart SIBO test?
You need a break of two weeks after stopping probiotics before you can do the Smart SIBO test.

Can I take Laxatives the night before the Smart SIBO test?
Unfortunately not – laxatives would interfere with the test results. If your laxatives are prescribed please discuss with your doctor whether stopping them for 1 day is OK for you. You can take laxatives if needed on the day of the test  – after you have finished taking your breath samples.

Do I need to stop any supplements before doing the Smart SIBO test?
You need to stop probiotics for 2 weeks before the test. Digestive aids such as digestive enzymes and betaine HCL – stomach acid, should be stopped the day before the test.

Do I need to stop taking any medication before I do the Smart SIBO test?
Please do not stop any medication without the consent of your Doctor. In the past it was believed PPI’s needed to be stopped before testing, this is no longer the case. You can take the test whilst using PPI’s but on the day of the test please take your PPI after you have completed the test. Laxatives should not be taken the day before the test.

Can I drink water the night before the test when fasting?
Yes, drinking water is allowed whilst fasting.

I have just had a colonoscopy – Can I still do the Smart SIBO test?
You must wait at least 1 month after a colonoscopy before doing the Smart SIBO test.

I have just had some Barium studies – Can I stil do the Smart SIBO test?
You must wait at least 1 month after a colonoscopy before doing the Smart SIBO test.

The test Kit and doing the Smart SIBO test.
Should I remove the grey rubber around the needle of the breath collecting kit?
No, Please don’t remove it. It helps to produce a good seal around the vial.

There is a hole in the blue breath collection bag. Should I tape it up?
The hole is there on purpose. Please don’t tape it up. It helps to get the correct breath sample.

Have you any tips re taking the breath sample?
Please have a look at the video that explains how to take the sample but feedback I have been given is that stand in front of a mirror may help you to see what you are doing.

Should I be able to see my breath in the test tube?
You won’t be able to see your breath go into the test tube nor will you see any condensation.

What our customers are saying about us

"Wow, thank you so much for sending the results so quickly! Of course I wish the results were negative after this year-long journey of treating SIBO, but at least I finally made progress on the methane"

CM 21.11.17

"We both enjoyed speaking to you and we did really appreciate your time and patience during the consultation. Thank you for all the advise and support."

AC 27.7.17

"I did speak to Emma and she made lots of sense, so I’m hoping the tests she has recommended will be able to help with my son’s diagnosis."

AW 25.7.17

"Sue thank you for going above and beyond. I will not hesitate to contact SN should I need further testing or have any referrals in the future.."

SL 8.9.16
Smart SIBO test is part of the Smart Group

Smart Nutriton Ltd; Sedgebrook House, Radley Road, Halam, Nr Newark, Notts, NG 22 8AQ
Ph: 01273 775480

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