For patients who suffer from IBS (irritable bowel syndrome), SIBO (small intestinal bacterial overgrowth), or similar conditions, the low FODMAP diet could be helpful in overall symptom improvement.

FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols, which are short chain carbohydrates found in commonly eaten foods. This diet is an elimination trial of certain foods categorized as FODMAPs, that trigger and exacerbate gastrointestinal symptoms, like bloating, gas, abdominal pain or discomfort, and altered bowel habits.

Dr. Treyzon recommends a two-week trial of the low FODMAP diet. Following the two-week elimination phase is a controlled reintroduction of food or food groups back into your diet to determine which foods are tolerated and which are not. During the reintroduction phase, your diet should continue to be low FODMAP except for the challenge/ reintroduction food.

These are the categories you should follow for each reintroduction phase, indicating example full serving portions of foods within each FODMAP category:

Phase: Polyols

• 1 peach
• ½ cup blackberries
• 1-2 prunes
• ½ cup mushrooms
• ¼ – ½ avocado

Phase: Fructose

• 1 teaspoon of honey or agave nectar
• ½ cup sugar snap peas
• 2 figs

Phase: Fructans

• 1-2 slices of wheat bread
• 1 clove of garlic
• 1-2 scallions (white and green part)
• ¼ onion

Phase: Galacto-oligosaccharides

• ½ cup beans (garbanzo, black, kidney)

One new food from only one FODMAP category should be reintroduced every 3 days. Each 3-day phase of reintroduction should be focused on one new FODMAP group, as people will often respond similarly to foods in the same category.

Day 1: Start with half portionDay 2: Increase portion by double, unless you experience symptoms from Day 1, then continue the same portion from Day 1Day 3: Increase portion by double, unless you experience symptoms from Day 2, then continue the same portion from Day 2For example, if wheat is being reintroduced, ½ slice of bread may be eaten on Day 1, increasing to a full slice on Day 2 and then 2 slices on Day 3 if still asymptomatic.

If there are no issues on the 3rd day of the reintroduction phase, this food can be added back into your diet. After the 3-day reintroduction, return to a fully restricted low FODMAP diet for three days before challenging a new food group. This will assure that developed symptoms are not due to an overlap of food categories. After trialing all the FODMAP groups, new 3-day food reintroductions could be implemented with new foods, without having to repeat periodic full FODMAP restrictions.

References:

• Phillips, Wendy, and Janelle Walker. “When a Registered Dietitian Becomes the Patient: Translating the Science of the Low FODMAP Diet to Daily Living.” Edited by Carol Rees Parrish, Nutrition Articles, University of Virginia School of Medicine, May 2018, med.virginia.edu/ginutrition/wp-content/uploads/sites/199/2018/05/Low-FODMAP-Diet-May-18.pdf.

Author Fiona Miao Patient Care Coordinator