Do you have gas, abdominal bloating, or abdominal pain after eating?
Have you ever eaten something and within a short while realized that your stomach is so bloated that you cannot button your pants?
Do you have belching or flatulence?
Do you have heartburn or nausea?
Do you have constipation, diarrhea, or both (symptoms of IBS, or irritable bowel syndrome)?
Any amount of bloating is not normal. If you have gas or bloating on a regular basis, you may have food sensitivities, most common being gluten and dairy, and/or a gut infection, such as SIBO.
What Is SIBO?
SIBO stands for small intestinal bacterial overgrowth. It is a condition caused by an abnormally high number of bacteria in the small intestine. While the digestive tract is full of bacteria, in a healthy system, the small intestine contains only small amounts of bacteria. The large intestine or the colon is where you have the highest concentrations of bacteria.
SIBO can manifest in several different ways:
- Some strains of bacteria may feed off certain carbohydrates and break them down into short-chain fatty acids, producing gas and causing bloating.
- Another strain of bacteria may break down bile salts before your body has a chance to use them for the digestion of fats. As a result, you have fat malabsorption and diarrhea.
- Another strain of bacteria may produce toxins that damage the lining of the small intestine, causing leaky gut and preventing your body from absorbing the nutrients you need.
Causes Of SIBO
Bacteria are normally kept at low levels in the small intestine (<100 thousand/mL) by:
- GI secretions that kill bacteria,
- intestinal mobility, also called the migrating motor complex which sweeps the small intestine clean between meals and at night, and
- the ileocecal valve, which prevents back flow from the colon into the last part of the small intestine.
Unlike the small intestine, the colon has a large bacterial population (100 billion/mL) where they perform many helpful activities. However, a number of factors may result in the migration of normal bacteria from the colon to the small intestine, leading to SIBO:
- Low stomach acidity compromises digestion
- Damage to the nerves or muscles in the gut from diseases such as type 2 diabetes or scleroderma (systemic disease that involves the hardening of connective tissues in the body).
- Celiac disease (autoimmune disorder that results in damage to the lining of the small intestine when foods with gluten are eaten)
- Slow motility of food through the intestine
- Physical obstructions in the gut, like scarring from GI surgeries, Crohn’s disease (inflammatory bowel disease), diverticuli (small pouches in the wall of the small intestine trapping bacteria instead of passing it on to the colon), or tumors.
- Medications that disrupt the normal gut flora and the body’s defense mechanism, such as antibiotics, acid-blocking drugs, and steroids.
- Diet high in sugar and refined carbohydrates, as well as alcohol abuse.
Symptoms Of SIBO
The indications of SIBO mirror the symptoms of other gastrointestinal disorders, including IBS which affects about 10-15% of the population. As a matter of fact, SIBO is a common cause of IBS. In a study from The American Journal of Gastroenterology (2003), SIBO is involved in up to 84% of the IBS cases.
Initial symptoms usually involve the GI tract only. As the disease progresses, the bacterial overgrowth may affect other body functions. The following are some common SIBO symptoms, although a person with SIBO does not need to have all of these symptoms:
- Gas, bloating, or flatulence.
- Abdominal pain or cramping
- Diarrhea, constipation, or both.
- Nausea and/or vomiting
- Food intolerances, e.g. gluten, dairy, and fructose.
- Skin problems, e.g. acne, eczema, and rosacea.
- Weight loss
- Fat malabsorption
- Vitamin B12 as well as other vitamin and mineral deficiency
- Chronic illnesses such as fibromyalgia, chronic fatigue syndrome, diabetes, pancreatitis, neuromuscular disorders, and autoimmune diseases.
Hydrogen Breath Tests are currently the most commonly used tests for SIBO. They are simple, noninvasive, and safe.
Breath testing measures the hydrogen (H) and methane (M) gases produced by bacteria in the small intestine that have diffused into the blood, then lungs, for expiration. H & M are gases produced by bacteria, not by humans.
Patients drink a sugar solution of glucose or lactulose after a 1 or 2 day preparatory diet, which eliminates the types of food that feed the bacteria, allowing for a clear reaction to the sugar drink. The amount of H and M gases produced during the 2 to 3-hour transit time in the small intestine are then measured and compared to the baseline level prior to taking the sugar drink.
1. Lactulose Breath Test
Humans cannot digest or absorb lactulose. Only bacteria have the proper enzymes to do so. After they consume lactulose, they make gas. If there is an overgrowth, it will be reflected in the levels of H and/or M.
The advantage of this test is that it can diagnose overgrowth in the distal end (the last 17 feet) of the small intestine, which is thought to be more common.
Lactulose Breath Test requires a doctor’s prescription.
2. Glucose Breath Test
Both humans and bacteria absorb glucose. Glucose is absorbed within the first 3 feet of the small intestine, therefore, if H and/or M are produced during this test, it reflects an overgrowth in the proximal or upper end of the small intestine.
The advantage of this test is that it can accurately diagnose proximal overgrowth (first 3 feet). The disadvantage is that it cannot diagnose distal overgrowth (the latter 17 feet) of the small intestine, which is thought to be more common. Therefore, if glucose testing is negative, a lactulose test is still required to rule out distal SIBO.
In the U.S. Glucose Breath Test kits can be ordered online and performed at home without a doctor’s prescription.
How To Combat SIBO
Similar to Candida (yeast) overgrowth, those who are susceptible to SIBO tend to have relapses after treatment. Hence, the key is to control the symptoms and address any underlying associated illnesses, as it may not be possible to completely “cure” SIBO.
1. Kill the bugs
There are primarily 2 ways to treat SIBO – antibiotics and herbal antimicrobials. Be aware that some people may need to do multiple rounds of antibiotics and/or herbal antimicrobials to clear the overgrowth.
Rifaximin (Xifaxan) is the most common antibiotic prescribed by doctors to treat SIBO. Sometimes, Neomycin is used in conjunction with Rifaximin. Some studies showed success rate of up to 91% in eradicating SIBO (measured by hydrogen breath test) with 94% symptom improvement.
Herbal antimicrobials –
For naturopathic physicians and other naturally oriented practitioners, they prefer to use herbal antimicrobials instead. A multi-center study, including Johns Hopkins, found herbal therapies are at least as effective as Rifaximin with similar response rates and safety profiles.
The multi-center study used 2 herbal combination formulas, at a dose of 2 caps 2X a day for 4 weeks for each formula:
- Biotics FC Cidal with Biotics Dysbiocide, or
- Metagenics Candibactin-AR with Metagenics Candibactin-BR
Apart from these, there are many other herbal antimicrobial formulas that are effective against SIBO. For example, Biocidin is a potent broad-spectrum botanical combination, containing bilberry extract, noni, milk thistle, echinacea, goldenseal, shitake, white willow, garlic, grapeseed extract, black walnut, raspberry, fumitory, gentian, tea tree oil, galbanum oil, lavender oil, and oregano oil. Dosage is 10 drops 3X a day for at least a month to 3 months, depending on severity of symptoms.
2. Modify your diet
Bacteria eat carbohydrates. When you eat a diet heavy in carbs, bacteria will have a field day. Hence, the best strategy is to adopt a diet that starves the bacteria by limiting carbs, especially certain types of carbs that are hard to digest and easily fermentable, leading to gas production. These include:
- Resistant starch. These starches are hard to digest and absorb and may cause fermentation. Commonly found in legumes and certain whole grains, fruits and vegetables.
- Fiber. Since fiber cannot be digested or absorbed, excessive intake may cause fermentation.
- Sugar alcohols. Sorbitol, mannitol, xylitol, lactitol, and isomalt are poorly digested and absorbed, and may cause fermentation.
Safe foods for SIBO
Meats, eggs, and seafood
Nuts and seeds (in small quantities) – almond, macadamia, pecan, pine nut, pumpkin seed, sesame seed, sunflower seed, walnut.
Fruits (in small quantities) – banana (ripe), blueberry, boysenberry, cantaloupe, cranberry, grapefruit, honeydew, kiwifruit, lemon, lime, mandarin, orange, passionfruit, raspberry, rhubarb, star fruit, strawberry, tangelo.
Grains – rice (jasmine, short grain, and sushi rice are best) and quinoa.
Vegetables – alfalfa, bamboo shoots, bean sprouts, bok choy, carrot, celery, choy sum, eggplant, endive, ginger, green leafy vegetables, lettuce, olives, parsnip, potato (Russet), pumpkin, red bell pepper, spinach, squash, tomato, turnip, zucchini.
Oils and fats
Tea and coffee
Almond and coconut milk, unsweetened
Dry white and red wines, hard liquor (unsweetened).
Sweeteners – stevia and erythritol (a sugar alcohol which is not fermentable)
Foods that may worsen SIBO symptoms
Dairy products with lactose
Beans and lentils
Dried fruits and fruit juices
Fruits – banana (unripe), apple, apricot, avocado, blackberry, cherry, date, fig, grapes, longan, lychee, mango, nectarine, papaya, peach, pear, persimmon, plum, prune, watermelon.
Grains – barley, corn, oat, rye, wheat.
Vegetables – artichoke, asparagus, beet, broccoli, brussels sprouts, cauliflower, cabbage, chicory, dandelion, edamame, fennel, garlic, green bean, green bell pepper, leek, mushroom, okra, onion, peas, plantain, shallots, spring onion, sugar snap peas, sweet corn, sweet potato, taro, yam.
Sweetener – agave, artificial sweetener, corn-based sweeteners, fructose, honey, maple syrup, molasses, sugar, sugar alcohols (except erythritol).
Sugary alcoholic drinks
Additives – Beta glucan, inulin, gum.
Note that merely modifying your diet will only mitigate your symptoms. You need to combine diet with either antibiotics or herbal antimicrobials to effectively combat SIBO.
3. Do not snack between meals
Eating frequently interferes with the cleansing waves of the small intestine which get rid of food byproducts, waste, and bacteria. Because the cleansing waves can only occur when you are not eating, the more meals you have per day, the less time your body has for such cleansing waves, making it easier for the bacteria to remain in the small intestine.
4. Drink plenty of water
Adequate fluid intake throughout the day is critical. If your diet does not include enough water, it becomes more difficult for your body to have proper bowel motility. Slow motility of food through the intestine may promote the development of SIBO.