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Small Intestinal Bacterial Overgrowth & How It Relates To Fibromyalgia

Small Intestinal Bacterial Overgrowth & How it relates to fibromyalgia

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Studies show that small intestinal bacterial overgrowth (SIBO) occurs in 90 to 100 percent of fibromyalgia patients. Dr. Alex Vasquez, author of Fibromyalgia In A Nutshell says that fibromyalgia is the result of SIBO and that treating bacterial overgrowth results in significant alleviation of FM symptoms. This prompted me to write this post about small intestinal bacterial overgrowth…what SIBO is, the symptoms and how to treat it.

Our intestines consist of two major subdivisions: the small intestine and the large intestine. The small intestine is much smaller in diameter but is much longer and more massive than the large intestine. The intestines are an important part of the immune system, especially the small intestine.

Normal bacteria that are part of the small intestine help protect against bad bacteria and yeast that are ingested. They help the body absorb nutrients, and also produce several nutrients and vitamins.

Research has revealed that gut bacteria perform a host of useful functions. These include interacting with the immune system, producing vitamins such as vitamin K, stimulating the release of hormones involved in the storage of fats and influencing mood and our feeling of well-being.

What Is Small Intestinal Bacterial Overgrowth?

Small Intestine Bacterial Overgrowth is a chronic overgrowth of bacteria in the small intestine. SIBO is not caused by a single type of bacteria. It is an overgrowth of various types of bacteria that should normally be found in the colon (large intestine).

Understanding Fibromyalgia

Bacteria overgrowth interferes with normal digestion, the absorption of food and leads to damage of the lining of the intestine. Eventually, the bacteria enters the bloodstream and cause problems with the immune system. The immune system’s reaction to the bacteria causes fatigue, body pain and burdens the liver.

Finally, the bacteria excrete acid, which in high amounts causes neurological and cognitive symptoms.

Symptoms Of SIBO

The main symptoms of SIBO are those of Irritable Bowel Syndrome (IBS):

  • Abdominal gas and bloating
  • Abdominal pain and cramps
  • Constipation, diarrhea or both
  • Mucus in the stool

Other symptoms may include:

  • Heartburn, acid reflux
  • Nausea, vomiting
  • Vitamin and mineral deficiencies
  • Food sensitivities
  • Headaches
  • Joint pain
  • Fatigue
  • Brain fog
  • Skin rashes or eczema
  • Respiratory symptoms such as asthma
  • Depression and/or anxiety

SIBO may be an underlying cause or a major factor in all of the following diseases: acne rosacea, anemia, autism, celiac disease, cystic fibrosis, chronic fatigue syndrome, diabetes, diverticulitis, fibromyalgia, GERD (gastroesophageal reflux disease), hypothyroidism/Hashimoto’s thyroiditis, IBD (inflammatory bowel disease) such as Crohn’s and ulcerative colitis, IBS (irritable bowel syndrome), muscular dystrophy, rheumatoid arthritis and many others. You can see a full list of associated diseases at SIBO Info.

Diagnosing SIBO

The most common way to diagnose SIBO is with a breath test. The breath test involves drinking a prepared glucose or lactose solution, then measuring the presence of methane and hydrogen gasses. There is a 24-hour preparation period before taking the test. The first 12 hours require a specific diet and the last 12 hours require a fasting period. After drinking the solution, the patient produces breath samples every 20 minutes over a 3-hour period. The test is performed in a doctor’s office, hospital, clinic or with an at-home test kit.

SIBO Treatment

Treatment involves reducing the bacteria, healing the intestinal lining and preventing relapse.

  1. Antibiotics – The most common prescribed antibiotic used to kill SIBO is Rifraximin. However, using antibiotics can also have a negative impact on the good bacteria in the gut. With that in mind, many people choose to try an herbal antibiotic such as enteric coated peppermint, garlic, oregano and golden seal.
  2. Diet – Bacteria primarily feed off of sugars and starches in the diet (both refined sugars and natural sugars). So it is essential to eliminate all refined sugars from the diet and most starchy foods. Keeping your diet low in carbohydrates will starve the bacteria. Established SIBO diets are:
    • Specific Carbohydrate Diet (SCD) – The Specific Carbohydrate Diet is a group of foods which are grain-free, sugar-free, starch-free, and unprocessed. The diet is an all natural way to break this cycle of bacteria and yeast overgrowth by eliminating the food sources they feed on. This book, Breaking the Vicious Cycle by Elaine Gottschall can help you understand the diet.
    • Gut and Psychology Syndrome Diet (GAPS) – The GAPS diet is based on the Specific Carbohydrate Diet. 85% of everything you eat daily should be made out of meats, fish, eggs, fermented dairy, and vegetables. Baking and fruit should be kept out of the diet for a few weeks, and then be limited to snacks. Homemade meat stock, soups, stews and natural fats are the main staples of this diet. Gut and Psychology Syndrome by Dr. Natasha Campbell-McBride can help fully understand the GAPS Diet before you start. Starting the diet incorrectly may lead to unnecessary diarrhea or constipation.
    • Low FODMAP Diet – FODMAPs is an acronym referring to Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are the names for a collection of molecules found in food, that can be poorly absorbed by some people. The Low FODMAP diet has two phases. The first phase restricts all high FODMAP foods for 6 to 8 weeks. The second phase is where the type and amount of FODMAPs are identified so that the longer term diet can be established. Dr. Sue Shepherd developed the low FODMAP diet in 1999. This book, The Complete Low-FODMAP Diet by Dr. Shepherd and Dr. Peter Gibson is a complete reference guide about the low-FODMAP diet.

    You can follow one or a combination of these diets.


    Several studies have connected fibromyalgia with the gut, emphasizing a strong relationship between fibromyalgia and bacterial overgrowth in the small intestine. Researchers discovered that the degree of bacterial overgrowth detected in the small intestine has a direct relationship with the severity of fibromyalgia. Some even suggest, small intestinal bacterial overgrowth may lead to fibromyalgia.

    Since small intestinal bacterial overgrowth can contribute to pain, your diet can help alleviate FM symptoms and protect your gastrointestinal tract and nervous system.

    Small Intestinal Bacterial Overgrowth & How It Relates To Fibromyalgia

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9 comments… add one
  • Great article Sue – dysbiosis is such a major issue with ME/CFS/Fibromyalgia and a really important aspect to address for recovery. Personally, not so keen on anti-biotics as they gut is already so unbalanced, but of course it always depends on the individual. Thanks for sharing this great article. 🙂

    • Hi, Dan. I agree with you on the antibiotics. I think the over-use of antibiotics has done way more harm than good. I watched your videos and added your book: CFS Unravelled to my wish list just a few days ago. So I was pleasantly surprised to see you left this comment on my blog. Thank you.

  • Thank you for this. I’ve been doing tons of research and I’m glad to see that there is more than one way to skin the proverbial cat. I’m so tired and in so much pain, though. I think that is why so many continue to suffer. The solutions require more energy than the sufferer can manage. I just wish there was a food service (like Nutrisystem) that was affordable and specifically for sibo sufferers so that people that are too tired and in too much pain to cook could actually get better.

    • Hi, Amy. A food service would be nice. I have often wished that too.

  • This is so interesting because I went to see a Dr. to lose weight. He put me on a diet that was highly restrictive. Basically it was no sugar and no carbs. While on this diet, the fibromyalgia pain,which had been debilitating, disappeared almost completely. I basically stayed on this diet for 4 years with no recurrence of th fibro symptoms. Then I went off this diet had added some sugar and carbs back in, not a lot. I got sick and was on two rounds of steroids. I had a huge fibro flare. Because of the steroids I gained some of the weight back. The Dr. recommended the diet again for both the fibro symptoms and the weight gain. As I have started back on the diet, I am already feeling the symptoms start to reside.

    • Hi, Janet. Glad to hear you are feeling better. I am being reminded of how important diet is. I have been feeling awful for months and finally realized it was because I started eating sugar again.

  • Hi Sue,
    Thank you so much for writing this article, I found it to be very helpful!
    I’ve had Fibro for as long as I can remember and have had RA for the past 11 years.
    The list of meds I’m on is ridiculous (Humira and Morephine just two name a few) and they just keep adding more every year while Never addressing the root cause! Well, I’ve had enough! I’ve decided to heal myself through diet/nutrition. As a person who has never studied nutrition it’s a very daunting task, as I’m sure you can imagine!
    Your article is pointing me in the direction I need to go, so Thank You, again! I love your Blog! Best wishes, Lynnie

    • Hi, Lynnie. I am glad I could help. Diet is the best place to start. A few years ago, I didn’t know squat about nutrition and I remember how overwhelmed I felt. The first thing I did is cut out sugar. That alone, made a big difference. As I cut an unhealthy food out of my diet, I added a healthy one in. It is hard to give up foods you love forever so I set my goal as 90/10. Ninety percent of my diet has to be healthy, nutritious, anti-inflammatory foods. Good luck and thank you!


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