If you are bloated and you have thyroid issues, SIBO may be to blame.
A 2012 research study found that more than HALF of people with low thyroid function were battling SIBO. If you’re struggling with bloating, indigestion, constipation/diarrhea, anxiety/depression, histamine reactions, eczema, rosacea, unexplained weight loss, unexplained weight gain, poor immune system function, fatigue, or nutrient deficiencies – you may be one of those people.
What is SIBO?
Our large intestines are home to trillions of bacteria. These bacteria help with everything from immune system function to the production of feel-good hormones like serotonin.
But if these bacteria migrate up into the small intestine, it can wreak havoc.
Small intestinal bacterial overgrowth (SIBO) is not an infection – it’s an overgrowth/abnormal accumulation of normal bacteria in the small intestine. When fermentable carbohydrates are consumed (from fruit, vegetables, grains, dairy) the bacteria feed off the carbohydrates and produce hydrogen, methane, and/or hydrogen sulfide gas. The gas production can lead to a wide variety of symptoms.
Symptoms and consequences of SIBO include:
- Diarrhea, constipation, or alternating constipation and diarrhea
- Abdominal pain/cramping
- Bloating and gas, which often increase throughout the day
- Foul-smelling gas
- Poor bile production, which results in decreased fat absorption
- Low stomach acid production
- Histamine intolerance (which can result in hives, itchy skin, sneezing, runny nose, and other allergy-like symptoms)
- Systemic sclerosis
- Weight loss due to malabsorption
- Weight gain due to slowed transit time
- Increased intestinal permeability (aka “leaky gut”)
- Vitamin deficiencies including vitamin D, vitamin E, vitamin A and B12
- Mineral deficiencies including iron and zinc deficiency
- Tingling sensation after meals
- Light sensitivity
- Autoimmune disease
There are three types of SIBO – hydrogen, methane, and/or hydrogen sulfide-dominant. Hydrogen-dominant SIBO typically results in diarrhea or alternating constipation/diarrhea, and methane-dominant SIBO typically results in constipation. Hydrogen sulfide SIBO typically results in foul-smelling gas, tingling sensations, and/or light sensitivity.
If you have SIBO, GI symptoms like gas, bloating, nausea, diarrhea and constipation tend to get worse throughout the day, and they get worse after consumption of high FODMAP foods like garlic, onion, cauliflower, asparagus, dairy products, and beans (more information on FODMAPs later in this article).
What Causes SIBO?
SIBO often results because the migrating motor complex is not firing like it should. The migrating motor complex (MMC) is a pattern of electrical activity that is triggered by the vagus nerve, a nerve that begins at the base of the brain and travels all the way down to the gut. The MMC sweeps the intestines during periods of fasting. It acts as a housekeeper and sweeps any remaining undigested food, cellular debris, and bacteria down the digestive tract into the large intestine.
A typical person has 8-12 MMC “waves” every 24 hours. If you have SIBO it could be as little as 1-2 waves every 24 hours.
source: PLOS One
Another common reason for SIBO is digestive enzyme deficiency. Your stomach acid, bile, and pancreatic enzymes all work to keep bacteria under control in the small intestine. Medications, antibiotics, poor diet, and underlying bacterial infections can all result in enzyme deficiency.
An underactive thyroid often results in both decreased activation of the MMC and low stomach acid production, both of which increase the risk of developing SIBO. This is especially the case if you have been dealing with an underactive thyroid for a long period of time.
Thyroid working just fine? Here is a comprehensive list of factors that increase the risk of developing SIBO:
- C-section birth
- Low probiotic intake
- Vegetarian diet/high carbohydrate diet (even if they are healthy carbohydrates)
- H2 blockers or proton pump inhibitors (Prilosec, Prevacid, Nexium, Pepcid, Zantac, etc.)
- Antibiotic use
- Opioids and/or NSAID use
- High stress levels
- Nerve or muscle damage (due to c-sections or other abdominal/pelvic surgeries, neuro disorders, diabetic enteropathy, etc.)
- Food poisoning
- Underactive thyroid
- Hormone imbalance
- Immune imbalance/dysfunction
- Underlying bacterial infections
- Underlying viral infections
- Mold toxicity
- Neck/back injury (which can compromise the Vagus nerve)
- Alcohol consumption
- Frequent eating (no time for the MMC to fire!)
A breath test is the best way to determine if you have SIBO. Stool tests only reflect what is going on in the large intestine, and organic acid testing does not differentiate between the large and small intestine.
The SIBO breath test is performed at home over the course of three hours. You should be given a specific prep diet for the 24 hours leading up to the test. During the test you will consume a glucose (sugar) solution and breathe into a test tube at specific intervals to collect gas measurements.
The timing of your body’s gas production is key. In a “normal” person methane and hydrogen gases will be produced after three hours, once the sugar solution reaches the large intestine. In someone who has SIBO, the methane and/or hydrogen levels will increase sooner.
There are other possible “positive test” scenarios that are not as black-and-white, so it is important to work with a Functional Medicine dietitian or other practitioner who is familiar with SIBO testing.
How To Fix SIBO
Using antibiotics alone to treat SIBO has a 67% relapse rate, so I don’t recommend going that route. I have successfully used natural antimicrobials for the vast majority of my clients, but sometimes (if the SIBO is severe and persistent) antibiotics can be helpful in conjunction with other supportive supplements and the right diet.
The three things to focus on when treating SIBO are:
- Decrease overgrown bacteria with diet and botanicals
- Restore bacteria balance with specific probiotics
- Optimize migrating motor complex function
The Truth About the Low FODMAP Diet
Some people make the mistake of using a low FODMAP diet to “treat” SIBO. This can actually be counter-productive.
A low FODMAP diet limits high FODMAP foods.. Each letter in “FODMAP” stands for a different type of fermentable carbohydrate (fructose, oligosaccharides, disaccharides, etc.). Foods that are high in FODMAPs include onion, garlic, cauliflower, apples, instant coffee and more.
Eating a low FODMAP diet can make treatment less effective. If you completely remove these carbohydrates the bacteria can become dormant and the antimicrobial/antibiotic won’t be able to kill it off. Including FODMAP foods in your diet on a daily basis increases the effectiveness of treatment, whether you use antibiotics or natural antimicrobials.
A low FODMAP diet can provide relief from SIBO symptoms, so if you are extremely sensitive to high FODMAP foods you can include them just with your dinner meal. If you tolerate the high FODMAP foods well you can include them during the day as well.
Regardless of whether you use a low FODMAP diet for symptom management or not, it is important to minimize sugar, refined carbohydrates (bread, pasta, crackers, etc.), and alcohol consumption. This is important while eradicating SIBO, and it is important to continue to minimize these to keep SIBO away in the future.
Antimicrobial – Botanical antimicrobials can be used to decrease the overgrown bacteria. I prefer antimicrobials over antibiotics because they are:
- Just as effective as antibiotics
- Cheaper than antibiotics (~$75-150 vs $100-1,000)
- Have fewer potential side effects
Prokinetic – Supporting motility is a key factor in eradication of SIBO. Prokinetics are NOT laxatives. They do not stimulate bowel movements. Rather, they stimulate the migrating motor complex.
Probiotics – Regular probiotics are contraindicated for SIBO because they can actually make SIBO worse, so it is important to use a probiotic specifically formulated for SIBO. Spore-based probiotics rebalance the gut flora without adding to the overgrowth, and they support the immune system as well.
Fiber – Hydrolyzed guar gum is an excellent fiber supplement that improves efficacy of antimicrobial treatment (whether you use antibiotics or botanicals), works as a gut adaptogen to relieve both constipation and diarrhea, assists in production of short-chain fatty acids for gut health, and improves intestinal motility. The powder can easily be added to water, coffee, tea, or smoothies. It is important to slowly work your way up to max dosage, because drastic increases in fiber over a short period of time can actually make GI issues worse.
Methane-Dominant SIBO – Atrantil is an important addition to methane-dominant SIBO because it works on the methane-producing bacteria and can aid in relief of constipation. Allimax or Allicin are good alternatives if Atrantil is not effective or is not tolerated.
Others – Other helpful supplements include gut repair formulas (with L-glutamine, zinc carnosine, aloe, etc.), alkaline salts and/or binders, and supplemental enzymes. If I have learned anything while working with clients who have SIBO, it is that every client is different and treatment needs to be individualized to achieve optimal results.
Eradicating the bacterial overgrowth is important, but preventing relapse is an often overlooked aspect of treatment. It is important to determine why you developed SIBO in the first place, and address those root causes. Maybe meals need to be further spaced out, sugar intake needs to be decreased, thyroid health needs to be addressed, the Vagus nerve needs some work, mitochondria need to be repaired, etc.
No matter how severe your SIBO, it can be fixed! Find a knowledgable practitioner who has experience with SIBO that can help you determine why it developed, how to fix it, and how to keep it away.
Having trouble finding a practitioner in your area? I see clients virtually via phone and video chat and I am more than happy to work with you! Contact me for more information on how to become a client.