Though no one likes to talk about it, roughly 60 to 70 million Americans suffer from digestive problems and while doctors have trouble diagnosing exactly what's causing the issue, there is one way to ease symptoms and relieve pain, called a "low-FODMAP diet." Essentially this is a way of eliminating foods that may be the likely culprit, to see if symptoms clear up as the result of this diet change. 

Digestive problems can be linked to food intolerances or allergies that may be near-impossible to detect by blood work or an allergy "scratch" test. That's why more medical professionals are suggesting anyone with issues try the low-FODMAP diet as a natural way to alleviate symptoms, before adding back in food groups one by one, to figure out which food group is the worst offender. Following a low-FODMAP diet has been effective in "up to 86% of patients with IBS find improvement in overall gastrointestinal symptoms as well as individual symptoms such as abdominal pain, bloating, constipation, diarrhea, abdominal distention, and flatulence following the diet," according to a study.

The low-FODMAP diet has been used by medical professionals in recent years to help patients suffering from gastrointestinal disorders, such as Irritable Bowel Syndrome (IBS), which is a catch-all phrase for anything that causes gastro distress, or Celiac Disease, which is an allergy to gluten, the protein that is found in wheat products.

FODMAP, which stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols, are naturally occurring sugar molecules in the fruits, vegetables, and legumes that the body has trouble digesting.

Foods that need to be eliminated on a low-FODMAP diet include:

  • wheat and rye
  • legumes (beans, chickpeas, lentils)
  • dairy (milk, yogurt, cheese)
  • onion, garlic, shallot, leek
  • broccoli and cauliflower
  • caffeine
  • celery
  • artichoke
  • asparagus
  • High-fructose fruits
  • apples
  • peaches
  • mangos
  • figs
  • honey and agave nectar
  • blackberries
  • lychee
  • sugar-free sweeteners in diet soda and gum

In order to not eliminate everything all at once (and have little plant-based foods to choose from), doctors suggest eliminating one FODMAP food group at a time, such as not eating fruit one day and then cutting out dairy the next, until your body tells you what it is that has been causing the bloat and gastric distress. Here is the list of FODMAP foods to eliminate:

High-FODMAP foods to eliminate, one at a time:

  • Fruits like  apple, clingstone peach, mango, nashi pear, pear, sugar snap pea, tinned fruit in natural juice, watermelon, apricot, avocado, cherry, prune, lychee, nectarine
  • Dairy: regular and low-fat cow, goat, and sheep milk; ice cream, Yogurts: regular and low-fat yogurts, soft and fresh cheeses
  • Vegetables: artichoke, asparagus, cauliflower, beetroot, broccoli, Brussels sprouts, cabbage, fennel, garlic, leek, okra, onions, peas, shallots,  mushrooms, snow peas
  • Cereals: rye and wheat cereals when eaten in large amounts (eg, biscuits, bread, couscous, crackers, and pasta)
  • Legumes such as  baked beans, chickpeas, lentils, and red kidney beans

Eating a diet high in FODMAP foods, such as sugar, starch, and fiber, can lead to gas, bloat, and stomach pain or diarrhea. This is because the small intestine (which lies below the stomach and above the large intestine) has trouble breaking down these types of foods,  leading the body to try even harder, and increasing the amount of fluid it secretes in an effort to break down the sugar and fiber. The combination of gas in your stomach and excess digestive fluid leads people to experience bloat and pain and results in "poor digestion."

The goal of a low-FODMAP diet is to find the food that triggers your symptoms

The goal of a low-FODMAP diet is to eliminate foods one by one until you find the trigger food (or foods) causing your pain. Those suffering from nonstop stomach pain relating to food sensitives or allergies should reach out to a doctor since there could be serious causes not related to diet, and doctors recommend not doing a low-FODMAP diet for longer than six weeks. Here is how to do it, according to Monash University, a top university in Australia.

The 3-Step FODMAP Diet Guide

  • Swap high FODMAP foods for low-FODMAP foods for 2-6 weeks.
  • Reintroduce one FODMAP at a time, increasing the serving size each day for three days, while assessing your digestion. (Re-introducing foods can take up to 8 weeks.)
  • Once you find the foods you can and cannot tolerate, simply avoid the trigger foods.

Once you pinpoint the aggravating foods, you should be able to get back to a less restrictive diet, which is important since many of these FODMAP foods are full of healthy nutrients and should not be avoided for long if they don't cause gastro distress.

How to Follow a Low FODMAP Diet While Eating Plant-Based

A low-FODMAP diet means cutting back on fiber-rich foods but that doesn't mean you can't eat any fruits or vegetables. Plant-based foods that classify as low-FODMAP include soy, dairy-free milk alternatives, grains, nuts, seeds, and certain legumes. The goal is to find foods that are easy to digest and don't harm your gut or identify methods that allow you to eat whole food without suffering. "Eating cooked food seems to be easier to digest," even those foods that cause issues for some people, according to Dr. Angie Sadeghi, a specialist in gastroenterology based in Newport Beach, California, on a recent webinar hosted by Forks Over Knives on the topic of How to Eat to Beat IBS and Heal Your Gut.

Eat these low-FODMAP foods, according to a study:

  • Soy products like tofu, tempeh, soy milk, seitan
  • Vegetables like eggplant, carrots, tomatoes, bamboo shoots, bok choy, cucumbers, ginger, potatoes, celery, green beans, and lettuce
  • Fruit like bananas, blueberries, grapefruit, grapes, honeydew melon, orange and strawberry, raspberries
  • Grains like quinoa, rice, oats, gluten-free pasta
  • Milk like hemp milk, almond milk, rice milk, coconut milk
  • Nuts like almonds, macadamia nuts, peanuts, pine nuts, walnuts (eat about 10-15 nuts)
  • Seeds like chia, poppy, pumpkin, sesame, and sunflower

How to do low-FODMAP on a plant-based diet

As you eliminate healthy whole foods like legumes or cruciferous vegetables, if you find that they are not the cause of your problems, re-introduce them since the healthy fiber, protein, antioxidants, and nutrients are key to eating a healthy plant-based diet. So try incorporating small amounts of these healthy whole foods back into your diet in small amounts of about 1/4 of a cup daily, according to the Monash University plan.

Fiber foods are essential for a healthy gut and should be slowly increased back into your diet points out Dr. Sadeghi, who adds that eating a low-FODMAP diet can cause more problems than it cures.

"I am not a fan of low-FODMAP for your health, because the foods you eliminate are good for us. You may be hurting your gut, not helping it," says Dr. Sadeghi. She recommends cutting dairy out of your diet before any other food, which has helped many of her patients manage their symptoms.

A low FODMAP diet isn't a weight loss plan and shouldn't be followed long-term

One caveat: People use a low-FODMAP diet as a restrictive way of eating or a type of disordered eating, which is why doctors don't recommend it for longer than six weeks.  "As a restrictive diet, the low-FODMAP diet carries risks of nutritional inadequacy and of fostering disordered eating, which has received little attention," according to a study on the controversial nature of the diet. As foods are eliminated, the dieter is deprived of vital nutrients found in whole foods. Low-FODMAP dieting is meant to be a short-term approach that doesn't restrict eating but helps find the food(s) to avoid and ease IBS symptoms or pain.

To follow the low-FODMAP plan you should avoid most legumes but you can have small amounts of butter beans, chickpeas, lentils, and lima beans since these are not 1/4 of a cup daily.