Is low-fermentation eating the answer to SIBO?
Written by: Kelly Martin
Published on: November 3, 2022
Hypothesis and new research
Some early observations support this concept (or parts of the theory), and there is scientific interest in elucidating exactly what is at work.
Nine years ago, a caesarean section complication landed Krystyna Houser in the hospital with an MRSA infection and a long treatment with strong antibiotics. When she recovered, she didn’t fully recover: She found herself dealing with persistent bloating, brain fog and mood swings. She spent the next two years enduring endoscopies, colonoscopies and blood tests. Even after ruling out celiac disease and Crohn’s disease, no doctor identified what was wrong with her or was able to help her get better. One of her doctors referred her to a psychiatrist and dismissed her symptoms as psychosomatic.
The turning point in Houser’s disease was meeting Cedars-Sinai physicians Mark Pimentel and Ali Rezaie, pioneers in gut microbiome and motility science and more recently the authors of The microbiome connection. Pimentel and Rezaie diagnosed Houser with bacterial overgrowth of the small intestine, or SIBO. As the name suggests, SIBO is defined by an imbalance of bacteria in the gut that can cause life-disrupting symptoms. Some are obviously gastrointestinal—gas, bloating, diarrhea, constipation, abdominal pain—while others, like brain fog, are harder to pin down.
The breath test that identifies SIBO is quick, readily available, non-invasive and inexpensive. But Houser’s previous doctors hadn’t tried it. Because SIBO shares symptoms with irritable bowel syndrome, Houser says, most doctors make an IBS diagnosis and don’t look any further even if treatments don’t work. SIBO sufferers on average, go six years before you get a proper diagnosis.
Once Houser’s SIBO diagnosis was confirmed, the path to remission was clear: Pimentel and Rezaie put her on an initial three-week elemental diet consisting only of a predigested nutrient formula—essentially feeding tube fluid—to starve the bacteria in her small intestine. (Houser says it was horrible, but it jump-started her recovery.) Then they had her transition to low-fermented eating, or LFE, a protocol they developed to dramatically reduce symptoms for long-term SIBO sufferers without the guesswork of an elimination diet.
The basics of low-fermentation eating
The goal of LFE is to limit how favorable the gut environment is for bacterial overgrowth. It consists of foods that bacteria are unlikely to metabolize and ferment—without completely restricting carbohydrates, so patients can maintain the protocol long-term. Ideal LFE foods include:
Refined carbohydrates, including bagels, white or wheat bread (but not multigrain or whole wheat), pasta, egg noodles, polenta, quinoa, white rice, and corn or flour tortillas.
Meat and eggs. Avoid legumes and soy-based meat alternatives, including tempeh and tofu.
Non-cruciferous vegetables, including arugula, kale, spinach, avocado, beets, corn, eggplant, peas, green beans, mushrooms, leeks, jicama, sweet potatoes, pumpkin, squash and tomato.
Fresh fruit. Shoot for one portion at a time of apricots, berries, melon, cherries, citrus, kiwi, mango, peaches, nectarines, persimmons, papaya, plums and pomegranate. (Avoid apples, bananas, dates, pears, and figs; dried fruit is generally not well tolerated.)
All-milk and low-lactose dairy. Ghee, lactose-free milk and cottage cheese and small amounts of butter are okay. With cheese, choose Parmesan, aged cheddar, Manchego and Gruyère, which are typically well tolerated.
Nuts and seeds, except chia and flax.
most drinks, including broth, coffee, seltzer, tea, and alcohol, are okay. But avoid soda and anything with high fructose corn syrup.
(You can find the full list of LFE approved foods – and which foods to avoid –here.)
LFE’s long-term approach is in contrast to low FODMAP diets— the existing standard of care for SIBO patients — which are so restrictive that doctors typically don’t recommend staying with them for more than a few weeks before working to wean them off.
Timing of meals for SIBO
Also an important factor, according to Pimentel and Rezaie: spacing meals at least four hours apart. When we allow the bowel to empty between meals, says Pimentel, our small intestine makes a physical movement to clean itself out. It pushes anything that cannot be digested into the large intestine for disposal. But if we don’t allow those cleansing waves—they only happen when the gut is empty—dirt builds up in the small intestine and ferments, exacerbating bacterial overgrowth.
3 recipes with low fermentation
It took a year and a half after the diagnosis for Houser to feel like himself again. She has been flare-free ever since. And she credits LFE with helping her get her life back: She’s back in restaurants and hosting dinner parties. The SIBO-friendly cookbook she co-wrote with dietitian Robin Berlin, The good LFE cookbook, launched last April. It’s a collection of the most delicious, comforting recipes Houser is making at home these days, like Gruyère pizza, creamy chocolate mousse, and juicy pulled pork.
This article is for informational purposes only. It is not, and is not intended to be, a substitute for professional medical advice, diagnosis or treatment and should never be relied upon for specific medical advice. To the extent this article contains medical or medical advice, the views expressed are those of the quoted expert and do not necessarily represent the views of goop.
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