Many people with Hashimoto’s feel significantly better when they remove reactive foods, replenish nutrient depletions with restorative foods and supplements, and support the gut with probiotics. But what if those steps alone don’t work? You have to dig a bit deeper.
It took more than the implementation of the strategies above for me to resolve all my symptoms related to Hashimoto’s. In fact, in some cases, my attempts to produce healing led to the development of additional, different symptoms altogether. Searching for the solution that will work for you can sometimes feel like trying to find a needle in a haystack, but the right combination of protocols for you is out there.
When symptoms don’t subside in response to what might be considered the standard approach in functional medicine—removing, replenishing, and repairing—there is a good chance that you have an unaddressed infection.
There are many infections that have been implicated in triggering Hashimoto’s, but the most common ones I see in my clients include H. pylori, yeast overgrowth, Blastocystis hominis, and reactivated Epstein-Barr virus. Additionally, people with hypothyroidism may have SIBO, or small intestinal bacterial overgrowth. While this is not technically an infection, SIBO does have a bacterial component and can be a trigger, consequence, or exacerbating factor for Hashimoto’s! In fact, a 2007 study found that about 50% of people with hypothyroidism have SIBO, while a 2017 study found that levothyroxine use can contribute to the development of SIBO!
What Is SIBO
SIBO stands for small intestinal bacterial overgrowth. Our small intestine is meant to be relatively clear of bacteria, while the large intestine houses most of our bacterial friends and foes. In some cases, bacteria from the large intestine may make their way up and overgrow into the small intestine.
Once you have SIBO, it can lead to intestinal permeability and contribute to a long list of digestive symptoms including acid reflux, belching, bloating, and irritable bowel syndrome (diarrhea, constipation, or mixed type). SIBO often presents with bloating after eating and the annoying “I woke up with a flat stomach and now I look pregnant syndrome” caused by bacteria in the small intestine making too much gas.
Conditions like IBS, hypothyroidism, fibromyalgia, and restless leg syndrome have all been tied to SIBO.
SIBO can also cause a depletion of vitamin B12 and iron, and lessen levels of digestive enzymes like lactase (digests lactose in dairy) and amylase (digests starch), making it more difficult to digest many foods.
If you’ve noticed that fibrous foods, fermented foods, histamine-containing foods, prebiotics, cruciferous foods, and/or the use of probiotics seem to cause a flare up in your digestive symptoms, there’s a good chance you have an overgrowth of bacteria in your small intestines.
Also, if you’ve found that using antibiotics or antimicrobial herbs, even when used for unrelated reasons, makes you feel better, this could also indicate the presence of SIBO. Substances with antimicrobial properties can suppress the bacteria, leading to temporary relief of symptoms.
Additionally, people who feel better when fasting and skipping meals and have the flattest stomachs when they first wake up are likely to have SIBO, as this will prevent the bacterial from gorging on our food, producing gas and replicating.
What Causes SIBO
This overgrowth can be caused by issues such as low stomach acid, antibiotic use, the use of acid-suppressing medications (Pepcid, Protonix, Nexium, Prilosec, and Omeprazole are some potential names), slowed gut transit (where food moves along the gastrointestinal tract too slowly), and food poisoning, among others. Hypothyroidism in itself may contribute to SIBO because of its propensity to slow down gut motility. A 2017 study also tied the use of levothyroxine to SIBO, however, I’m not sure if this is a chicken or egg thing…
How to Test for SIBO
While yeast overgrowth and most sources of gut infection can be detected in a stool test, SIBO is best revealed in a breath test. This is because the breath allows us to determine the presence of gas-producing bacteria. The gas is emitted because of fermenting bacteria, which will usually produce measurable levels of hydrogen and methane.
Because SIBO is a hot new topic in the gut world, some more progressive conventional medicine doctors may be willing to test you for it—although you may have to be proactive and ask for the test yourself. Functional medicine practitioners, gastroenterologists, and major Academic Treatment Centers will have access to advanced diagnostic tests, possibly administered using a breath-testing machine.
Otherwise, you can order a SIBO breath test kit that uses Lactulose to stimulate the bacteria to release their giveaway gases. SIBO breath tests are offered by the following labs: BioHealth Laboratory, Commonwealth Laboratories, and Genova Diagnostics.
It’s important to find out if you have SIBO because treating a bacterial overgrowth can not only help regenerate your sugar digestive enzymes, greatly improving digestion, it may also result in remission from Hashimoto’s in some cases.
SIBO can be a root cause, consequence, or exacerbating factor of Hashimoto’s. I have seen people with Hashimoto’s resolve symptoms like IBS, restless leg syndrome, low ferritin, and low B12 by treating SIBO, and in some cases, I’ve also seen thyroid antibodies reduced—and even go away—with SIBO treatment.
SIBO Treatment Options
There are a few protocols which can be used in the eradication of SIBO. You can try a pharmacologic approach, which relies on antibiotics, and/or an herbal approach that focuses on the use of antimicrobial herbs.
My clients have also had some success using specific dietary approaches, such as the elemental diet, the Specific Carbohydrate Diet, the Low FODMAPS diet, or the GAPS diet.
Even if you don’t choose to take a dietary approach, it is recommended during the treatment of SIBO (or suspected SIBO) that you limit starchy foods, fiber, and the use of probiotics that contain prebiotics like fructooligosaccharides (FOS), inulin, Arabic gum, as well as foods with high prebiotic foods (this is similar to a low FODMAPS diet, see below).
Foods with high prebiotic content include chicory root, Jerusalem artichoke, dandelion, garlic, leek, onion, and asparagus. For a full overview of the low FODMAPs approach, please check out Root Cause.
Peppermint oil has been found to be helpful for SIBO as well, however, most brands of peppermint oil contain soy, so drinking peppermint tea may be a better alternative.
According to Dr. Allison Siebecker, creator of the informative website SIBOinfo.com, the antibiotics metronidazole, rifaximin (Xifaxan™), and neomycin have been used to treat small intestinal bacterial overgrowth because of their ability to stay in the intestines, which prevents them from causing systemic adverse events. Most of my clients who have used this approach have reported positive results, though it’s important to note that not all insurance companies cover Rifaximin—and the out of pocket cost may be high!
- Rifaximin 1200 mg daily for 14 days for hydrogen-producing bacteria
- For methane-producing bacteria (which are more likely to cause constipation): Rifaximin 1600 mg per day x 10 days, combined with neomycin (1000 mg per day x 10 days) or metronidazole (750 mg per day x 10 days)
Herbal and Alternative Treatment
Berberine, oregano, and garlic are all herbal antimicrobials that can help eliminate bacterial overgrowth.
- Candibactin-BR (an herbal formulation containing Berberine): two capsules, three times per day for 60 days
- Oil of oregano two capsules, three times per day for 60 days
- Add for methane-producing bacteria: Allicillin (garlic extract): two capsules 3 times per day for 60 days
There are four possible dietary approaches to getting rid of SIBO: the elemental diet, the Specific Carbohydrate Diet, the Low FODMAPS diet, or the GAPS diet.
The elemental diet is a liquid diet that is free of non-digestible substances such as fiber, complex carbohydrates, and protein structures. It contains our essential macronutrients in a state that requires little to no digestion and results in complete absorption and has been traditionally used for rehabilitation of severely malnourished individuals, bowel inflammation, and diarrhea.
The elemental diet is a low-residue diet that is composed of free amino acids and fat in liquid form. Amino acids, glucose, fat, and vitamin/mineral supplements are utilized instead of food. Because it results in reduced secretion of pancreatic and gastric juices, this diet gives the stomach and pancreas a rest from activity and allows for healing and reduction of inflammation to take place.
Additionally, free form amino acids allow for the body’s own protein to be spared, helping the rest of the body heal quicker.
An elemental diet may be extremely beneficial in kick-starting the thyroid healing process. This diet causes a rapid shift in bacterial flora within one to two weeks. Since it is an extremely low-residue diet, it requires no digestion and does not provide any food to the pathogenic bacteria, thus starving them.
Clinical trials have shown that this diet is effective in reducing SIBO within two weeks in people with IBS, resulting in a substantial improvement of symptoms in as many as 80% of people.
The drawbacks of the diet are that amino acids are expensive and taste pretty disgusting, if not properly prepared. People report feeling nauseated after drinking the solution, and aspiration has resulted when people would lie down too quickly following ingestion.
Commercially available formulas (e.g. Vivanox®) contain a lot of artificial ingredients people with Hashimoto’s may not tolerate. They also include a lot of carbohydrates, which can cause high blood sugar and harm adrenal function.
In recent times, the company Integrative Therapeutics came up with a cleaner version of the elemental diet—the Physician’s Elemental Diet. This formulation has become my go-to recommendation for people with Hashimoto’s.
Some critics of the elemental diets also noticed that symptoms sometimes return after a period of time ranging from months to years. I think this is likely because people go back to their junk food diets too soon. However, if an elemental diet was followed by a grain-free FODMAPS diet, SCD Diet, or similar diet, this could result in permanent remission.
I do not recommend attempting the elemental diet in a person with compromised adrenal function and other types of infections like parasitic infections. Elemental diets should be used under the supervision of a health care professional and in the case of confirmed SIBO.
A homemade elemental diet is available in the Companion Guide to the book, which you can download at thyroidpharmacist.com/guide. As this diet requires the purchase of expensive amino acids, however, it can be quite pricey.
Specific Carbohydrate Diet/GAPS Diet
The Specific Carbohydrate Diet (SCD) and the Gut and Psychology Syndrome (GAPS) Diet eliminate grains, sugars, and starches and only allow carbohydrates to be eaten in the form of fruits and honey, and certain kinds of specifically fermented yogurts. It is very similar to the Autoimmune Paleo Diet [AIP] well-known in the Hashimoto’s community, with the exception that it does not allow sweet potatoes due to their starchy content and allows other foods like nuts, seeds, and nightshades that are not AIP approved. I love the website SCDlifestyle.com if you’re looking for more information on these dietary approaches.
Low FODMAPs Diet
The low FODMAP diet is considered an effective nutritional therapy for certain digestive disorders, including SIBO. By removing foods high in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs), this diet essentially cuts off the food supply to the bacteria that may be running amok in your intestines. This is an easy way to describe eliminating possible carbohydrates that could be fermented by gut bacteria.
A low FODMAPs diet can help SIBO by multiplying the flora we need for absorption and to potentially starve the pathogenic flora. This happens by avoiding the foods that are fermented by pathogens.
There are certain foods, specifically onions, garlic, and beans, which will always be malabsorbed in all individuals—either with or without IBS. These three foods also cause gas production in all individuals. However, when pathogenic bacteria are present, toxic byproducts are produced, causing even more symptoms.
75% of individuals with IBS who follow this diet will see an improvement in symptoms.
Although the low FODMAPs allows fruits and vegetables, there are a few that are eliminated. For Hashimoto’s patients, the list is a bit refined due to eliminating dairy and all grains.
Foods to Consume
Fruit (limit to 1 serving)
Banana, berries (all but blackberry), melon (all but watermelon), cranberry, grapes, grapefruit, kiwi, citrus (all), passionfruit, rhubarb, tangelo, dried fruit to be eaten in small quantities
Alfalfa sprouts, bamboo shoots, bok choy, carrots, celery, eggplant, endive, ginger, green beans, lettuce, olives, parsnips, pumpkin, red capsicum, silver beets, spinach, squash, swede, sweet potatoes, taro, tomatoes
Arrowroot, psyllium husk, tapioca
Maple syrup (small quantities), olive oil
Foods to Avoid
Apples, mango’s, pears, tinned fruit, watermelon, avocado, green capsicum, lychee, longan, nectarines, peaches, pears, plums, prunes
Artichokes, asparagus, beetroot, cruciferous vegetables, fennel, garlic, leek, okra, onions, shallots, spring onion, mushrooms, corn, white potatoes
All grains – wheat, rye, rice, pasta, quinoa, crackers
Fructose, HFCS, chicory, dandelion, inulin, pistachio, legumes, all artificial sweeteners, xylitol, sugar
Here’s a graphic with an overview of high FODMAP foods, that you can save and refer to later:
The Importance of Retesting and Tips for Preventing SIBO Relapse
It’s important to retest for SIBO 5-14 days after the completion of the treatment protocol to determine if in fact the SIBO has been appropriately treated or whether it may be growing back.
One way to keep the bacteria from growing back is to ensure that you have sufficient stomach acid, something with which betaine with pepsin may be helpful. Prokinetic agents, that help to move food along and prevent bacteria from “snacking” on the food as it passes, such as low dose naltrexone, may also help prevent the recurrence of SIBO by supporting gastrointestinal motility.
Picking the Right Protocol for You
I advise you to discuss these potential protocols with your practitioner and let them help identify the best starting point for you based on your health history. While it may take some time, eradicating SIBO can allow for your gut to heal and, ultimately, resolve the intestinal permeability that may have been your Hashimoto’s trigger.
The first step is to get tested for SIBO and then make a plan from there.
Have you already been tested for SIBO? What methods have you tried to treat it?
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