What is FODMAP stacking

If you are on a low FODMAP diet and your symptoms have not improved or improved a little, you may be stacking the FODMAPs. “FODMAP stacking” is a term used to describe how FODMAPs from the same food group can add up in your gut and cause the symptoms. Even though you seem like you are eating all the green foods from the Monash University App, you may be piling up foods from the same sub-group in the same meal making it high in FODMAP.

Monash University Database lists foods using 3 lights system:

• Green light foods don’t have FODMAPs and can be eaten freely without possibly causing any symptoms. ⁠
• ⁠Yellow light foods can be eaten in moderation and may be tolerated by some people. ⁠
• ⁠Red light foods are high in FODMAPs and should be avoided because they most likely cause an adverse reaction. ⁠

If you are on a low FODMAP diet, your meals should consist mostly of green light foods. If you are able to tolerate yellow foods, go for it. However, when you add several green or yellow foods in 1 meal, you may be increasing the number of FODMAPs, which can later cause adverse symptoms.

Let me give you an example. ⁠

You want to make a homemade trailmix, so you mix all the nuts that are marked as “green” in the Monash University App. Let’s say you mixed walnuts, pecans, and Brazil nuts, but you want to add some sweetness and variety to your trailmix. You saw that raisins, dried Goji berries and cranberries are listed as green at a certain amounts and decide to add all three fruits to your dish. All these dried fruits contain fructans and you will probably won’t have any symptoms if you eat 1 serving of one fruit. However, if you add all 3 fruits to your trailmix, you are increasing the amount of fructans in one meal and this trailmix is not low FODMAP anymore since it contains the higher amount of fructans.

You may also stack your FODMAPs if you are grazing “green” or “yellow” light foods all day long. These foods can stack in your GI tract and may cause all the adverse symptoms of IBS, such as bloating, abdominal pain, diarrhea and/or constipation. For instance, for breakfast you had some cereal that you can tolerate but it contains some fructans, in an hour you ate some dried banana chips and in another 45 minutes you had some trailmix mentioned above, so what you did was you ate all the foods that contained fructans. Even though you ate small amounts of these foods, there is not enough time for them to travel further in the gut, so they add up. Depending on the person, this can trigger IBS symptoms.

What you can do to avoid FODMAP stacking

1. Space out your meals 3-4 hours apart: It will help the food to go further in the GI tract without accumulation.
2. Include FODMAP-free foods at each meal: You can eat “green” light foods freely since they won’t cause any symptoms. These are carrots, grapes, oranges and etc.
3. Use only 1 “yellow food” in a meal and pair it with “green” foods: If you are able to tolerate ”yellow” portions of some foods, don’t stack them, pair it with “green” foods. For example, if you want to make a salad, mix arugula, lettuce or both (both are green choices), cucumber (green), carrots (green), radish (green) and green pepper (1 medium is a yellow one).⁠
4. Eat a variety of foods: Eating different kinds of foods will ensure that you won’t get bored from eating the same thing over and over. You may be tempted to eat something different, which may be high in FODMAP. Besides, the more diverse your diet, the more diverse and happy your microbiome is.

Use these tips if you think that low FODMAP diet doesn’t work and you are still having the symptoms. Troubleshooting your actions before coming to a conclusion will ensure if the FODMAP diet is for you.