- What is the Low-FODMAP diet?
The Low-FODMAP diet was created more than five years ago, in Australia, by Susan Shepherd and Peter Gibson. This diet eliminates certain foods to improve the symptoms of functional gut disorders (FGD). Irritable bowel syndrome (IBS), a type of FGD, may be helped by this diet. IBS is the most commonly diagnosed gastrointestinal condition and over half of patients with IBS associate a trigger in their symptoms with eating a meal. (The ACG website has more information on IBS.)
FODMAP stands for Fermentable, Oligo-, Di-, Mono-saccharides And Polyols. FODMAPs are short-chain carbohydrates (sugars) that are highly fermentable (to ferment, is to go through a chemical change that results in alcohol) and poorly absorbed during digestion.
- What effects do FODMAPS have on the digestive system?
When FODMAPs reach the colon (large intestine), bacteria ferment these sugars, turning them into gas and chemicals. This stretches the walls of the colon, causing abdominal bloating, distension, and pain or cramping in many people. Other symptoms, such as diarrhea, constipation, and nausea, are also common side effects of FODMAP carbohydrates. Not everyone has the same reaction to FODMAPs. Ethnicity, genetics, and environmental factors (such as an individual’s microbiome, motility, immune system, and sensory system) may play a part in your body’s ability to tolerate these carbohydrates.
- When is a Low-FODMAP diet recommended?
Eliminating or restricting FODMAPs from the diet may greatly improve symptoms of FGD. In Australia, a Low-FODMAP diet is the main treatment for IBS. It was adopted by their National Therapeutic Guidelines. The Low-FODMAP diet can be adjusted to meet personal food and lifestyle preferences. Following a personally developed Low-FODMAP plan does not cure IBS, but it may lead to drug-free management of symptoms and better quality of life. As with any diet, it is important to discuss with your doctor and working with a GI trained dietician is also useful.
A number of studies suggest that limiting FODMAPs in the diet leads to improved symptoms in one-half to two-thirds of patients who follow this diet. Many patients see improvement in 1-2 weeks, though some may need to wait up to 4 weeks. Bloating and abdominal pain are the most likely symptoms to improve. Diarrhea is more likely to improve than constipation. If there is no improvement after 4 weeks, it is likely not worth continuing this diet.
A Low-FODMAP diet is not recommended for people without gastrointestinal symptoms. Also, if your IBS symptoms improve on the Low-FODMAP diet, you should eventually re-introduce FODMAPs, one at a time, to identify foods that trigger symptoms and those that do not. This will allow a more diverse diet. Keeping a personal food diary may help simplify this process
- What symptoms may be associated with FODMAPS?
As FODMAPs are poorly absorbed during the digestive process, they may pass to the large intestine (colon), where they are rapidly fermented by the bacteria that normally live in the colon. This makes chemicals called short chain fatty acids, as well as gas. This, in turn, leads to changes in the acidity and types of bacteria in the colon. The colon expands, which can lead to pain, bloating, and changes in bowel habits.
Diets rich in FODMAPs may increase symptoms in patients with FGD or IBS. However, the FODMAPs themselves are not the root of the problem. For that reason, patients may need to include other options to treat their symptoms. This may include medicine, exercise, meditation, hypnotherapy, etc.
- What are FODMAP carbohydrates?
Examples of FODMAP carbohydrates include polyols (sugar alcohols), which are found in many fruits, vegetables, and artificial sweeteners; lactose, which is found in milk products; fructose, which is the sugar found in fruits, high fructose corn syrup; fructans, which are found in wheat and some fruits and vegetables; and galactans, which are found in legumes (such as beans) and some vegetables. Some, but not all, fibers are rich in FODMAPs and may need to be limited.
- What foods are suitable, and what should be avoided while on a Low-FODMAP diet?
The following is a list of foods that have high amounts of FODMAPs. It is a difficult diet to follow, especially in the beginning. It may be beneficial to work with a dietician with experience in FODMAP diets to help tailor your diet. Patients can try slowly re-introducing foods if the overall diet is helping. Normally, within a week or two of following the Low-FODMAP diet, patients will begin to have major symptom improvement. It is important to remember that a Low-FODMAP diet is not a life-long diet, but one of removing problem foods and re-introducing foods that do not cause symptoms. You should strictly follow the diet for a few weeks. If you do not get any better, the diet can be stopped. If there is improvement, one can consider carefully reintroducing one food group per week to see if it causes any problems.
The food groups are listed below:
Apples, apricots, avocados, cherries, lychee, nectarines, peaches, pears, plums, and watermelon.
Bananas, blueberries, grapefruit, kiwi, lemons, limes, passion fruit, raspberries, cantaloupe, honeydew, and strawberries
Artichoke, asparagus, brussel sprouts, cabbage, cauliflower, green beans mushrooms, snow peas sprouts, and summer squash.
Bean sprouts, bell peppers, bok choy, carrots, celery, chives, cucumbers, eggplant, kale, lettuce, potatoes, pumpkin, radishes, spinach, tomatoes, winter squash, yams, and zucchini.
Artificial Sweeteners Sorbitol, mannitol, isomaltose, malitol, xylitol, polydextrose, hydrogenated starch Aspartame, sucralose, saccharin. Commonly found in various gum and candy as well. Lactose Dairy whey and high-lactose containing milks such as cow, goat, sheep, chocolate, buttermilk, and condensed milk, and whipped cream. Ice cream, cow’s milk-based yogurt, brie, cottage cheese, ricotta, and sour cream. Gelato or sorbet (though watch fructose content) and lactose-free yogurts. Aged hard cheeses tend to be easier to tolerate. Cheddar, Colby, parmesan, and mozzarella. Greek yogurt.
Limit: Butter, margarine, sour cream, half and half, cream cheese, Swiss cheese, goat cheese, feta cheese, cheddar, parmesan, and mozzarella contain lactose, although at lower amounts.
Non-Dairy Milk Alternatives Soy milk contains galactans and should be avoided as well, coconut milk, soy products, hummus, beans, and lentils. Lactose- free or lactaid milk, rice milk, almond milk, almond butter, and cashew milk. Fructose / Sweeteners Honey, agave, apples, cherries, dates, guava, honeydew melon, lychee, mandarin oranges, mangoes, peaches, pears, persimmons, star fruit, canned fruit in natural juices, dried fruits and less ripe fruits, corn syrup, high fructose sweeteners, coconut milk, fruit pastes (i.e. chutney, plum sauce, barbeque sauce, ketchup), rosé wine, port, and sherry Maple syrup, jams, marmalades, vegemite, table sugar, bananas, blackberries, blueberries, boysenberries, cranberries, grapefruit, kiwis, kumquats, lemons, limes, passion fruit, raspberries, and strawberries.
Limit: grapes, oranges, papaya, pineapple, and watermelon.
Fructans Starches Bread, pasta, semolina, flour tortillas, wheat-based bread and breadcrumbs. Wheat-based cereals, crackers, cookies, cakes, pasta, and pastries. Beer. Corn breads, gluten- free breads, pastas, cereals, as well as corn flakes, oatmeal, potato-based breads, rice-based noodles and breads, and wheat-free rye bread. Fruit. Grapes, mangoes, peaches, persimmon, pineapple, watermelon, and bananas. Grapefruit, lemons, limes, papaya, raspberries, strawberries, and blueberries. Vegetables Artichokes, asparagus, beets, broccoli, Brussel sprouts, cabbage, chicory, garlic, leeks, lettuce, okra, onions, radicchio, scallions, shallots, snow peas, and zucchini. Bean sprouts, bell peppers, bok choy, carrots, celery, chives, cucumber, eggplant, potatoes, pumpkin, radishes, spinach, tomatoes, turnips, winter squash, and garlic-infused oil. Galactans Plant based proteins such as beans, black-eyed peas, chick peas, kidney beans, lentils, lima beans, pinto beans, soy products, broccoli, Brussel sprouts, cabbage, green beans, and yellow beans. Eggs, nuts, quinoa, seeds, bean sprouts, bell peppers, bok choy, carrots, celery, chives, cucumbers, eggplant, potatoes, pumpkin, radish, spinach, and tomatoes.