First and foremost, FODMAP is an acronym that stands for Fermentable, Oligosaccharides (Fructans and Galacto-oligosaccharides — Wheat, Rye, Onions), Disaccharides (Lactose — Milk, Yogurt, Ice Cream), Monosaccharides (Fructose — Honey, Watermelon, Apples), And Polyols (Sorbitol, Mannitol, Maltitol, Xylitol — Apricots, Cauliflower, Chewing gum) (1).

Translation: FODMAPs are short-chain carbohydrates that are poorly digested in the small intestine and subsequently fermented by the bacteria near the end of the small and beginning of the large intestine — aka colon (1). This natural fermentation process produces hydrogen (as opposed to methane) gas, which often leads to bloating, flatulence and general discomfort. On top of that, FODMAPs also pull water into the intestines, contributing to diarrhea (2).

While FODMAPs do not directly cause any gastrointestinal disorders, they certainly can aggravate them (2). So for those diagnosed with IBS, Crohn’s disease, and the like, FODMAPs can increase the intensity of those painful, pre-existing symptoms. If this is the case, a low-FODMAP diet may be in order.

FODMAP does not signify “Unhealthy”While the idea of FODMAPS “fermenting” in your stomach doesn’t have a nice ring to it, it’s actually very important to feed your beloved “gut bacteria” (aka “intestinal flora”) that help keep your digestive tract functioning smoothly.

Therefore, FODMAPs are, for most people, “a clean source of energy, or may function like other prebiotic fibers, helping to support the friendly bacteria in the gut. However, in people who truly have FODMAP intolerance, they feed the wrong type of bacteria,” and potentially cause the onslaught of FODMAP-associated discomfort (2).

So it’s not like FODMAPs are, by nature, irritants devoid of any nutritional value. In fact, they help your body build a defense against intestinal irritation in the long term (3). This is why it is actually NOT recommended to go completely FODMAP-free, even if one is experiencing harsh IBS symptoms.

High FODMAP vs. Low FODMAP foodsFODMAPs are not the easiest to detect. To the average shopper, FODMAPs seem to appear in foods at random. It’s not like all fruits, or all nuts, are high in FODMAPs. However, there are a few general rules you can follow to get an idea of the FODMAP content of a given food.

FODMAPs are carbs, so most meats (proteins), oils, and butters (fats) are low-FODMAP (4). Also, it’s important to remember that some carbs, like starch, are long-chain, and FODMAPs are short-chain. While many starches are still considered FODMAPs (go figure), the take-home message here is that low-FODMAP and low-carb are not one and the same (2).

Foods High in FODMAPs:• Dairy Products: Milk, Yogurt, Ice Cream and Soft Cheeses (Cottage and Ricotta) • Fruits: Apples, Pears, Mangos, Watermelon, Stone Fruit (Peaches, Apricots, Cherries, Plums/Prunes, Nectarines, Blackberries and Grapefruit) • Vegetables/Legumes: Onion, Garlic, most Beans, Asparagus, Sugar Snap Peas, Cauliflower, Broccoli, Mushrooms, and Artichokes • Grains: Wheat (Bread, Pasta, Breakfast Cereals), Rye, and Barley • Nuts: Pistachios and Cashews • Sweets/Sweeteners: Sugar-Free Gum, Candy, Honey, Agave, and High-Fructose Corn Syrup • Beverages: Beer • Other: Chicory Root (5).

Foods Low in FODMAPs:• Meats/Proteins: Tofu, All Meats, Fish, Prawns, and Eggs • Dairy Products: Lactose-free Dairy Products and Hard Cheeses (including Brie and Camembert) • Fruits: Bananas, Blueberries, Grapes, Kiwi, Lemons, Limes, Melons (except for Watermelon), Oranges, Passionfruit, Raspberries, Strawberries, and Tomatoes • Vegetables: Alfalfa, Bell Peppers, Bean Sprouts, Bok Choy, Carrots, Celery, Cucumbers, Eggplant, Green Beans, Kale, Lettuce, Chives, Olives, Potatoes, Radishes, Spinach, Scallions, Squash, Sweet Potatoes, Turnips, and Zucchini • Grains: Brown Rice, Corn, Oats, Quinoa, Sorghum, and Tapioca • Nuts/Seeds: Almonds, Peanuts, Pine Nuts, Walnuts, Pecans, Sesame Seeds, and Sunflower Seeds • Sweets/Sweeteners: Maple Syrup, Molasses, Stevia, and most Artificial Sweeteners • Beverages: Water, Coffee, and Tea • Other: Most Fats and Oils (like Coconut and Olive Oil) and most Herbs and Spices (2).

Before Taking on a Low-FODMAP DietThis diet is not really for someone who gets the occasional “tummy ache.” Due to the benefits of having FODMAPs in one’s regular diet, it isn’t recommended that anyone begin a low-FODMAP diet unless they’re experiencing chronic symptoms of IBS or another GI disorder.

That being said, when someone embarks on this sort of diet, it’s almost always for the short-term (between 8 weeks and 6 months). In certain cases, athletes have been known to follow it for even just a few days as a “pre-event diet” if they typically experience stomach discomfort during strenuous activity (4).

How to Begin your Low-FODMAP DietThe diet consists of 3 phases: • Restriction: Eliminate all High-FODMAP foods from your diet to see if your symptoms improve. • Reintroduction: Bring those High-FODMAP foods back into your diet one at a time to identify which specific foods aggravate your GI symptoms. This will allow you to learn which foods you should limit or avoid altogether. • Personalization: Develop a personalized diet that agrees with your digestive system, while still providing your body with all the nutrients (and FODMAPs) it needs (6).

It’s always recommended to work with a dietitian when committing to a low-FODMAP diet. A FODMAP specialist can teach you the tricks of the trade, like how to check for hidden FODMAPs on processed food labels (4).

References:
  1. Krawiec, Sebastian. “Bold Flavors for Specialized Diets.” Whole Foods Magazine, 17 Nov. 2017, wholefoodsmagazine.com/grocery/features-grocery/bold-flavors-specialized-diets/.
  2. Gunnars, Kris. “FODMAP 101: A Detailed Beginner's Guide.” Healthline, June 2017, www.healthline.com/nutrition/fodmaps-101.
  3. Heiman, Mark L, and Frank L Greenway. “A Healthy Gastrointestinal Microbiome Is Dependent on Dietary Diversity.” National Center for Biotechnology Information, Mar. 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC4837298/.
  4. Taylor, Marygrace. “The Low-FODMAP Diet Is the Gut-Healthy Trend You Need to Know About.” Prevention, Apr. 2018, www.prevention.com/food-nutrition/healthy-eating/a19756314/fodmap-diet/.
  5. Van Dam, Lauren, and William D Chey. “The Low FODMAP Diet and IBS.” Whole Foods Magazine, Apr. 2015, wholefoodsmagazine.com/blog/low-fodmap-diet-and-ibs/.
  6. Rossi, Megan. “A Beginner's Guide to the Low-FODMAP Diet.” Healthline, Mar. 2017, www.healthline.com/nutrition/low-fodmap-diet.