The low FODMAP diet was developed at Monash University in Melbourne, Australia. It is an excellent diet relieving SIBO and IBS symptoms and is easier to adopt than an elemental or semi-elemental diet. Following the diet hopefully helps decrease opportunistic bacterial and yeast colonies within the small and large intestines by restricting fermentable FODMAP carbohydrates. Sadly, the low FODMAP diet also decreases probiotic colonies over time.^{1 2} FODMAP stands for fermentable, oligo, di, monosaccharides, and polyols. Mono-di-oligosaccharides are different types of carbohydrates. A polyol is a sugar alcohol that has lower caloric content than most other carbohydrates. The goal of the diet is to restrict the amounts of FODMAPS you consume to a bare minimum. The low FODMAP diet will hopefully reduce your symptoms if you suffer from SIBO.³ The extremely limited diet during the first week is to help reduce opportunistic bacterial and yeast colonies within your small intestine and large intestine that ferment FODMAPs. During this time, you might have some symptoms of a herx reaction. You might either develop constipation or have diarrhea briefly during this week as your gut microbiome becomes more acclimated to the new diet. During the third week, a less restricted FODMAP diet adds moderate FODMAP foods to see if your microbiome can now handle more FODMAPS without symptoms. FODMAPS must be added back slowly into the diet after the third week. I would add higher FODMAP fruits to the diet and increase them to about two to three servings per day. If you can tolerate an increase of fructose ingestion in your diet, slowly add lactose and other higher FODMAP foods. I would still avoid wheat, alcohol, processed sugar, polyols, and full servings of most food sources of FOS.

Examples of Different Foods That Are Restricted on a Low FODMAP Diet^{4 5}

Foods With Elevated Amounts of Fructans(FOS):

Artichoke, Spelt, Freekeh, Cous Cous, Cho Cho, Bourghal, Garlic, Leek, Onion, Spring Onion (White Part), Shallots, Wheat, Rye, Barley, Inulin, FOS Prebiotic Supplements, Watermelon, Cashews, Pistachios, Asparagus, Broccoli, Peaches, Almonds, Hazelnuts, Persimmon, Tamarillo, Choko, Nectarines, Pomegranates, Chicory Root, Snow Peas, Okra, Brussel Sprouts, Butternut Pumpkin, Amaranth, Savoy Cabbage, Grapefruit, and Beetroot

Foods With Elevated Amounts of Fructose:

Apples, Apricots, Cherries, Figs, Pears, Peaches, Mango, Watermelon, Guava (Unripe), High Fructose Corn Syrup, Agave Nectar, Dates, Honey

Foods With Elevated Amounts of Galactans:

Legumes, Soy Milk, Cashews, Pulses, Snow Peas, Hazelnuts, Peas, Taro, Yucca Root, Custard Apple, Beans

Foods With Elevated Amounts of Lactose:

Milk, Fresh Cheese, Ice Cream, and Custard

Foods With Elevated Amounts of Polyols:

Apples, Apricots, Avocado, Blackberries, Cherries, Lychees, Pears, Nectarines, Plums, Prunes, Watermelon, Cauliflower, Celery, Mushrooms, Snow Peas, Sweet Corn, Sweet Potato, and Sugar Alcohols / Sweeteners (Xylitol, Sorbitol, Mannitol, Isomalt, Maltitol)

What Foods Can I Eat on a Low FODMAP Diet?

Best App For the Low FODMAP Diet: Monash University Low FODMAP Diet App My version of the low FODMAP diet is divided into two phases. The first phase of the diet restricts you to meals that have low to no FODMAP potential and should only be followed for a week. The second phase of the diet includes low amounts of FODMAPS to acclimate your gut so that when you discontinue the diet you should be able to digest FODMAPS. The low FODMAP diet may limit food choices; however, you can still cook many different meals on a low FODMAP diet. Following a low FODMAP diet at restaurants might be challenging, but most Americans need to eat healthier home-cooked meals more often. There is some conflict about what foods are allowed on the low FODMAP diet and what foods should be avoided. Always compare my simple lists to the up-to-date Monash University Low FODMAP Diet App linked above. Also, everyone’s genetics, epigenetics, microbiome, digestive, and immune health are different, so just because a food is listed as low FODMAP, ingesting it may cause digestive symptoms. Keep a food diary, pay attention to what foods exacerbate your symptoms, and avoid them. My version of the low FODMAP diet is divided into two phases. The diet’s first phase restricts you to meals with low to no FODMAP potential and should only be followed for up to two weeks. The second phase of the diet, usually followed during the third week, includes lower amounts of FODMAPS than the standard diet to acclimate your gut so that when you discontinue the diet, you should be able to digest FODMAPS.

Low FODMAP – Low Fermentation Diet Safe Food List (Eat Organic and/or Non-GMO Certified When Possible) – First Week ^{6 7 8 9}

Carbs

Arrowroot, Buckwheat Flour (2/3 cup) Buckwheat Groats (3/4 cup), Buckwheat Noodles, Butternut Squash (1/3 cup), Corn (non genetically modified [GM]), Non GM Corn Flour and Meal (2/3 cup), Non GM Corn Pasta, Non GM Corn Tortillas (no added gums or fiber), Kelp Noodles, Lentils (1/2 cup canned), Mung Beans Sprouted (2/3 cup), Millet Flour (2/3 cup), Oats (oats, coarse oatmeal), Peanuts (thirty two peanuts), Plantain, Non GM Polenta, Potatoes (flour, starch, red, russet, yellow), Pumpkin (1/2 cup canned) Quinoa, Rice (brown, brown rice noodles, jasmine, flour, sushi) Rutabaga, Sorghum Flour (2/3 cup), Sweet Potato (1/2 cup), Tapioca Flour, Tapioca Starch, Taro (1/2 cup), Teff Flour (2/3 cup), Plain Non GM Tofu (2/3 cup)

Condiments

Hot Sauce (check for added FODMAPS), Organic Mustard, Organic Tamari Soy Sauce, Apple Cider Vinegar, Tomato Paste (no added FODMAP ingredients like garlic and onions), Homemade Broth (no FODMAPS), Homemade Mayo (no FODMAPS, good recipe: http://whole30.com/2014/05/mayo/)

Dairy / Dairy Alternatives

Almond Milk (no additives except vanilla extract, one cup), Hard Cheeses, Macademia Milk (no additives except vanilla extract, one cup), Rice Milk (no additives except vanilla extract, one cup), Yoghurt (goat lactose free)

Fats

Pastured Ghee, Pastured Lard, Macadamia Nut Oil, XCT Oil, Brain Octane Oil, Organic Extra Virgin Olive Oil, Extra Virgin Sesame Oil, High Oleic Sunflower Oil, Organic High Oleic Peanut Oil, Pastured Tallow, Pastured Bacon Fat

Fruit

Limit to Two Servings Daily, Must be Fresh, Not Canned Fruit: Acai powder (tablespoon), Blueberries (1/4 cup), Breadfruit, Cantaloupe (3/4 cup), Clementine, Cumquat, Carambola, Dragon Fruit, Durian, Grapefruit, Grapes (one cup), Guava (two medium ripe), Honeydew Melon, Kiwi (two small peeled), Lemons, Limes, Mangosteen (two medium), Oranges, Papaya, Passion Fruit (two fruits), Paw Paw, Pineapple (one cup), Prickly Pear, Raspberries (thirty berries), Rhubarb, Starfruit, Strawberries, Tamarind

Fish / Meat / Seafood / Eggs

Most fish / seafood / meat / eggs are permitted except processed meat with added FODMAPS.

Nuts / Seeds / Nut Butters

Limit to One to Two Servings Daily: Brazil Nuts, Chestnuts, Chia Seeds, Hazelnuts (ten nuts), Hemp Seeds, Macadamia Nuts (twenty nuts), Pumpkin Seeds, Sesame Seeds, Sunflower Seeds, Pecans (ten halves), Pine nuts (one tablespoon) Pumpkin Seeds, Walnuts (ten nut halves), Nut Butters (made with listed low-FODMAP nuts or ingredients)

Seasoning / Spices

Most are fine except for spices obtained from FODMAPS (for example, no, onion and garlic powder.)

Sweeteners

Dextrose (non-GMO), Honey (one teaspoon daily), Maple Syrup (one tablespoon daily), Stevia

Vegetables

Alfalfa (two cups), Arugula, Bamboo Shoots, Bean Sprouts, Bok Choy (one cup), Carrot, Chives, Choko, Choy Sum, Collard Greens, Cucumber, Eggplant (one cup), Green Onion(green part only), Kale, Kohlrabi, Lettuce, Mustard Greens, Nori, Olive, Oyster Mushroom, Parsnip, Radish, Red Bell Pepper, Silverbeet, Spinach, Squash, Swiss Chard, Tomato (common), Turnip, Turnip Greens, Water Chestnuts, Witlof, Zucchini (1/2 cup chopped)

Moderate FODMAP Diet – Moderate Fermentation Safe Food List (Eat Organic and/or Non-GMO Certified When Possible) – Third Week^{10 11 12 13}

Carbs

Arrowroot, Black Beans (1/2 cup drained), Buckwheat Flour (2/3 cup) Buckwheat Groats (3/4 cup), Buckwheat Noodles, Butternut Squash (1/2 cup), Corn (non genetically modified [GM]), Non GM Corn Flour and Meal (2/3 cup), Non GM Corn Pasta, Non GM Corn Tortillas (no added gums or fiber), Kelp Noodles, Lentils (one cup canned), Mung Beans Sprouted (2/3 cup), Millet Flour (2/3 cup), Oats (oats, coarse oatmeal), Peanuts (thirty two peanuts), Plantain, Non GM Polenta, Potatoes (flour, starch, red, russet, yellow), Pumpkin (1/2 cup canned) Quinoa, Rice (brown, brown rice noodles, jasmine, flour, sushi) Rutabaga, Sorghum Flour (2/3 cup), Sweet Potato (one), Tapioca Flour, Tapioca Starch, Taro (1/2 cup), Teff Flour (2/3 cup), Plain Non GM Tofu (2/3 cup), yam (one cup diced)

Condiments

Hot Sauce (check for added FODMAPS), Organic Mustard, Organic Tamari Soy Sauce, Apple Cider Vinegar, Tomato Paste (no added FODMAP ingredients Like garlic and onions), Homemade Broth (no FODMAPS), Homemade Mayo (no FODMAPS, good recipe: http://whole30.com/2014/05/mayo/)

Dairy / Dairy Alternatives

Almond Milk (no additives except vanilla extract, one cup), Hard Cheeses, Macadamia Milk (no additives except vanilla extract, one cup), Rice Milk (no additives except vanilla extract, one cup), Yogurt (goat lactose free)

Fats

Pastured Ghee, Pastured Butter (one to two tablespoons), Pastured Lard, Macadamia Nut Oil, XCT Oil, Brain Octane Oil, Organic Extra Virgin Olive Oil, Extra Virgin Sesame Oil, High Oleic Sunflower Oil, Organic High Oleic Peanut Oil, Pastured Bacon Fat, Pastured Tallow, Coconut (2/3 cup shredded)

Fruit

Limit to Two to Three Servings Daily, Must be Fresh, Not Canned Fruit: Acai powder (tablespoon), Avocado (1/2 cup). Blueberries (1/2 cup), Breadfruit, Cantaloupe (one cup), Clementine, Cumquat, Carambola, Dragon Fruit, Durian, Grapefruit, Grapes (one cup), Guava (two medium ripe), Honeydew Melon, Kiwi (two small peeled), Lemons, Limes, Mangosteen (two medium), Oranges, Papaya, Passion Fruit (two fruits), Paw Paw, Pineapple (one cup), Prickly Pear, Raspberries (1/2 cup), Rhubarb, Starfruit, Strawberries, Tamarind

Fish / Meat / Seafood / Eggs

Most fish / seafood / meat / eggs are permitted except processed meat with added FODMAPS.

Nuts / Seeds / Nut Butters

Limit to Two to Three Servings Daily: Brazil Nuts, Chestnuts, Chia Seeds, Hazelnuts (twenty nuts), Hemp Seeds, Macadamia Nuts (thirty nuts), Pumpkin Seeds, Sesame Seeds, Sunflower Seeds, Pecans (twenty halves), Pine nuts (one tablespoon) Pumpkin Seeds, Walnuts (twenty nut halves), Nut Butters (made with listed low-FODMAP nuts or ingredients)

Seasoning / Spices

Most are fine except for spices obtained from FODMAPS (for example, no, onion and garlic powder.)

Sweeteners

Dextrose (non-GMO), Honey (two teaspoons daily), Maple Syrup (one tablespoon daily), Stevia

Vegetables

Alfalfa (two cups), Arugula, Bamboo Shoots, Bean Sprouts, Broccoli (one cup), Bok Choy (one cup), Cabbage (one cup shredded), Carrot, Chives, Choko, Choy Sum, Collard Greens, Cucumber, Eggplant (one cup), Green Beans (fifteen beans), Green Onion(green part only), Kale, Kohlrabi, Lettuce, Mustard Greens, Nori, Olive, Oyster Mushroom, Parsnip, Radish, Red Bell Pepper, Silverbeet, Spinach, Squash, Swiss Chard, Tomato (common), Turnip, Turnip Greens, Water Chestnuts, Witlof, Zucchini (one cup chopped)

How to Improve the Low FODMAP Diet So It Works for You!

Some people have great results with the low FODMAP diet, and others do not. Can we optimize the low FODMAP diet to help you achieve symptom relief from gut dysbiosis while addressing its drawbacks? The low FODMAP diet should mainly be used for symptom reduction; it usually does not fix gut dysbiosis. The low FODMAP diet is not perfect, and long-term use may increase the time it takes for your digestive health to improve once off the diet. Issues associated with long-term use of the diet include:¹⁴

1. The diet may reduce probiotic bacterial colonies within your intestines. including Bifidobacteria and Lactobacillus.
2. The diet may reduce gut diversity. Studies have shown the more diverse your gut, the more likely you will have fewer digestive issues.
3. The diet may reduce SCFA production in your intestines, including butyrate.
4. The diet may slow motility because of the reduction of fiber and probiotic bacterial colonies within your intestines because of the diet.
5. The diet increases intestinal pH leading to a greater chance of intestinal dysbiosis.

How can these issues be addressed so that the low FODMAP diet can work for you? Supplementing specific prebiotics, fibers, and foods rich in SCFA’s may help make up the gut health deficits in the low FODMAP diet and improve your outcome when using the diet.

Ways to Reduce the Amount Of Probiotic Bacteria Lost on the Low FODMAP Diet

Well-fed probiotic bacteria keep our digestive system happy, helping to maintain our immune system, motility, mental health, and sleep. Most probiotic bacteria require FODMAPS in our diet to ferment to thrive and improve our microbiome diversity and health. Even though FODMAPS keep our probiotic flora happy, they feed some opportunistic bacteria, like Clostridia and Klebsiella. The low FODMAP diet works well in reducing hydrogen-producing bacteria.^{15 16} What can be done to reduce the loss of probiotic bacteria when on the low FODMAP diet? Increased intake of low fermentable fiber like acacia fiber may help. Using the prebiotic GOS (a FODMAP) may also help. GOS, even though it is a FODMAP, seems to feed the opportunistic bacteria less and increases probiotic bacteria colonies in the gut. Start with a small dose, like 1/4 teaspoon daily, to see if you can tolerate it and increase its dosage when tolerated. For people who cannot tolerate GOS because it is a FODMAP, the human milk oligosaccharide prebiotic 2′-FL might be better tolerated. Milk based prebiotics including GOS and 2-FL might not be tolerated well by people who are lactose intolerant or who can not tolerate dairy ingestion. Cellulose fiber is a low fermenting bulking agent that might increase Bifidobacteria in the colon. Even though it is not well known as a prebiotic, ingestion of collagen increased Bifidobacteria colonies. Acacia fiber, including Heather’s Tummy Fiber is well tolerated and has a low chance of causing bloating and discomfort. Start with small amounts of any of the low FODMAP fibers or prebiotics, mixed well in filtered water in the morning to see if it improves your gut health. Too much of any of these prebiotic recommendations may still create digestive issues in people with gut dysbiosis.^{17 18 19}

Increasing Fiber on the Low FODMAP Diet to Help Motility

Any of the above recommendations may help increase motility in the gut. One of the biggest complaints about the low FODMAP diet is that it worsens constipation. Proper fiber intake in our diet helps us keep our probiotic bacteria colonies intact, and in doing so, they help us accomplish critical digestive tasks. Our probiotic microbiome helps us assimilate our food better and produce serotonin, enhancing motility. You can also get more fiber and polyphenols in your diet by eating specific low-FODMAP sources if you can tolerate them. The starches on this list must be consumed hot; when cooled, resistant starch may cause digestive problems in people with an opportunistic overgrowth in their digestive systems. Finally, try to purchase organic or locally grown food whenever possible. Some of these foods include:

• Certified gluten free organic oatmeal (some people might have issues with the opioid peptide avenin in oats if they have issues with gluten ingestion. Avoid if you have celiac disease).
• Chia seeds
• Blueberries (1/4 cup) and raspberries (thirty berries)
• Melons (cantaloupe, honeydew)
• Oranges
• Spinach
• Arugula
• Rutabaga
• Organic potatoes with skin (avoid if you have issues with nightshades)
• Quinoa (avoid if you have an issue ingesting saponins)
• Organic brown rice
• Yam (one cup diced)
• Buckwheat
• Carrots
• Parsnips
• Plantains
• Low FODMAP nuts listed above
• Butternut squash (1/4 cup)
• Spaghetti squash (1/4 cup)
• Freshly cooked organic corn
• Eggplant (avoid if you have issues with nightshades)
• Sweet potato (1/2 cup)

In addition, maintaining proper hydration, using a Squatty Potty, movement (walking), chewing your food well, eating only three meals daily and during the daytime, and proper magnesium supplementation may help improve sluggish motility.

Obtaining SCFA’s From Your Diet to Improve the Gut While on the Low FODMAP Diet

Reduction in probiotic bacteria, including Bifidobacteria and Lactobacillus, from long-term diet changes, may reduce SCFA production in the gut. Short-chain fatty acid metabolism by the bacteria in our intestinal tract greatly improves our health. The production of acetate, for example, by Lactobacillus, creates many beneficial actions in the gut. Acetate has antimicrobial properties, enhances lipogenesis and cholesterol synthesis, improves gluconeogenesis, and reduces intestinal pH. The production of butyrate by some Clostridium strains and Bifidobacteria also improves our digestive health. Butyrate enhances the health of our enterocytes, has antimicrobial properties, improves mucosal integrity, reduces the formation of colon cancer cells, and increases energy levels.^{20 21 22 23} You can take supplemental acetate and butyrate, but these supplements are highly concentrated, and most people seem not to tolerate them as well as obtaining these SCFA’s in the diet. The easiest way to increase acetate is to ingest organic raw, unfiltered apple cider vinegar. You may need to avoid this if you have histamine issues; apple cider vinegar does contain histamine. Increasing butyrate ingestion is just as easy. Organic grass-fed butter, organic or raw European hard cheese, and organic pastured ghee are sources of dietary butyrate. However, most ingested butyrate feeds the upper gut digestive cells, not your colonic cells. Most people with digestive issues can tolerate at least one of these foods. Finally, taking a prebiotic supplement if needed, like GOS or 2′-FL, has been shown to increase SCFA acid production in the gut and increase concentrations of probiotic bacteria in the gut (GOS is a FODMAP and for some, might make bloating and gas production worse). Sadly, if you are suffering from Mycobacterium Avium paratuberculosis dysbiosis, dairy consumption, arabinogalactans, beef-sourced collagen, the prebiotic GOS should be restricted and instead be replaced with the prebiotic 2′-FL and the use of acacia fiber. Supplemental butyrate or non-dairy GOS dietary intake (small amounts of beans) may be needed in people with MAP dysbiosis.²⁴

Conclusion

The low FODMAP diet should only be used for a short period for symptom reduction if needed, and everyone suffering from SIBO should not use it. Its long-term effects on the probiotic microbiome are unknown. Two studies have shown that it may hinder recovery and cause relapses for people trying to return to a somewhat regular diet from a lack of a probiotic microbiome. There are ways to protect the probiotic microbiome slightly from a low FODMAP diet; they include ingestion of dietary SCFA’s, prebiotics, and low FODMAP sources of fiber. I still recommend the low FODMAP diet for people suffering from highly symptomatic SIBO to see if it relieves them.

Have questions about the low FODMAP diet, Gut Dysbiosis, or any other health issues?

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