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FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols—short-chain carbohydrates and sugar alcohols. Found in a variety of foods, they’re not fully digested and absorbed by some people, especially those who have IBS or other gastrointestinal issues. In the colon, bacteria feed on these undigested sugars, releasing gases that lead to bloating, cramping, and other symptoms. FODMAPs may also have an osmotic effect, meaning they draw water into the intestines, causing loose stools.
The IBS Fix?
A number of studies show that a low- FODMAP diet can reduce symptoms in people with IBS, and some studies suggest that a low-FODMAP diet is more effective than standard dietary interventions for controlling IBS. A low-FODMAP diet can also benefit Crohn’s disease, ulcerative colitis, and inflammatory bowel diseases (IBD).
If you do choose to follow a low-FODMAP plan, do it right. Maximize results and minimize adverse effects with this simple guide for what to eat, what to avoid, and how to do it right.
What To Eat, What To Avoid
The FODMAP diet is definitely restrictive in its initial phases. Here’s a simple guide:
Beans and legumes
Eat: Small amounts of canned black beans (canned beans are generally lower in FODMAPs). Soaking dried beans overnight then draining and rinsing before cooking also reduces FODMAP content.
Avoid: Kidney beans, split peas, chickpeas and hummus, soybeans, lentils, and most other legumes.
Eat: Blueberries, raspberries, strawberries, grapefruit, grapes, kiwi, cantaloupe, oranges, lemons, and limes.
Avoid: Apples, pears, cherries, mangos, figs, watermelon, dried fruit, blackberries, peaches, prunes, and plums.
Eat: Spinach, kale, chard, lettuce, carrots, tomatoes, bell peppers, celery, cucumbers, eggplant, green beans, parsnips, white potatoes, radishes, squash (except butternut, which is a moderate FODMAP food), turnips, and zucchini.
Avoid: Garlic, onions, artichokes, cauliflower, mushrooms, peas, celery, leeks, cabbage, shallots, asparagus, broccoli, Brussels sprouts, fennel, and sweet potatoes (4 ounces may be okay for some).
Eat: Hard and aged cheeses such as cheddar, Camembert, Parmesan, blue cheese, Havarti, and Swiss in moderation. Smaller amounts of cottage cheese, ricotta, cream cheese, feta, and Colby may also be safe.
Avoid: Milk, yogurt, soft cheeses, ice cream, sour cream, processed cheese foods and spreads, and whey protein, unless it’s labeled lactose-free.
Nuts and seeds
Eat: Almonds, peanuts, macadamia nuts, pine nuts, and sesame seeds.
Avoid: Cashews and pistachios.
Eat: Rice, quinoa, corn (avoid sweet corn), oats, and tapioca.
Avoid: Barley, rye, wheat, and any other gluten-containing grains such as Muesli.
Eat: Chicken, beef, turkey, lamb, fish, shellfish, eggs, firm tofu, tempeh, and edamame in moderation.
Avoid: Silken tofu, textured soy protein, and gluten-based foods like seitan.
Herbs and spices
Eat: Most fresh and dried herbs and spices, including rosemary, basil, tarragon, parsley, ginger, and chives.
Avoid: Garlic, onions, and seasoning blends with high-FODMAP ingredients.
Fats and oils
Eat: Olive oil, coconut oil, avocado oil, sesame oil, butter, and most other oils and fats in moderation.
Avoid: Oil-based condiments and salad dressings that may contain high-FODMAP ingredients such as garlic.
Eat: Stevia, coconut sugar (small amounts), maple syrup, and cane and brown sugar.
Avoid: Honey, molasses, high-fructose corn syrup, xylitol, mannitol, maltitol, sorbitol, inulin, chicory root extract, and agave.
Drink: Coffee, tea, vegetable juices, and small amounts of red or white wine.
Avoid: Beer, fortified wines such as sherry and port, milk, and soft drinks sweetened with high-fructose corn syrup.
How to Do the FODMAP Diet Right
The low-FODMAP diet is (or should be) a three-stage process. In the first phase, high-FODMAP foods are eliminated from the diet to ease gastrointestinal distress. In the second phase, some FODMAP foods are slowly and systematically reintroduced to determine which ones trigger symptoms. The third phase aims to personalize the diet, reintroducing as many foods as possible while avoiding FODMAPs that exacerbate discomfort. Here’s how it works:
PHASE ONE: Elimination.
Most plans completely eliminate all high-FODMAP foods from the diet for three to eight weeks. It’s important to be rigorous here. The plan likely won’t work if you’re only eliminating some—but not all—high-FODMAP foods. The good news is that you may feel relief in as little as a week (though it can take the full eight weeks for symptoms to ease).
PHASE TWO: Reintroduction.
Once your digestive symptoms have noticeably eased, you can slowly and systematically reintroduce some FODMAP foods to your diet. Few people are sensitive to all FODMAPs, so adding foods one at a time, in small amounts, can allow you to identify which types of FODMAPs you can tolerate, and in what quantity. (Ideally, you’ll work with a nutritionist to help you determine which foods to reintroduce, and in what order and amount.) This phase usually takes six
to eight weeks.
PHASE THREE: Personalization.
This step involves creating a long-term, personalized eating plan that reintroduces the safe foods identified in phase two. The goal is to eat a wide variety of foods and maximize fiber intake from low-FODMAP foods, while avoiding trigger foods. Because a person’s FODMAP tolerance can change over time, keep an eye out for symptoms, and revise as needed.