*All of the information I am providing is from what I have learned personally, and from what has worked for me personally. None of it is meant to supplement information or care from a professional like a Medical Doctor or dietician. Please seek experienced medical experts for individualized care and treatment*
In part two of my reintroduction I really want to give you all an in depth look into the preparation for reintroduction. You want to know what groups you're testing, what foods in that group you will test, and what portions to test. In addition, you want to know what symptoms to look out for, what to avoid doing on test days, and what the washout period is and why it's important. this is going to be very long, but if you are about to start reintroduction and feel like you have no idea what to do, this should significantly help you better understand what FODMAP reintroduction really is.
Just as a baseline, the carbohydrate groups you test during reintroduction are lactose, fructose, sorbitol, mannitol, oligosaccharides, and fructans. Fructans are tested in different groups due to differing levels of FODMAPs in fruits/veggies, grains, onion, and garlic. For this reason, I personally tested all four of the fructan categories separately. I also omitted the lactose category because I know I am lactose intolerant, and I also follow a vegan or plant based diet and did not feel the need to test a food group I would not be consuming. For food examples for testing, check out the Monash University FODMAP app. In the diary portion of the app, there is a button that allows you to track your reintroduction and shows you examples of foods you can test, in addition to their portion sizes (I have included the example of my own testing below for those of you without access to the app).
Before I began testing I made a schedule of testing. I laid out which carbohydrate group I was going to test, with which food, and in what portion for every week I was going to be testing. Although I did modify it a bit along the way, this helped me know what to expect out of my testing schedule and feel a little more at ease. There is no perfect way to test. You don't have to test a certain group first or last, just choose whatever order fits you best. Personally I loosely based it off what I thought would trigger me most and least, despite being very wrong about this, so I wouldn't really recommend that method. If you do not know how to spread out your testing head to my "My Experience with FODMAP Reintroduction part 1 post."
I used both wheat bread and pasta for fructan-grain testing (my wheat bread test wasn't clear enough so I retested this group with pasta), raisins and brussel sprouts for fructan-fruits/veggie testing (I did not tolerate raisins well but my dietician recommended I retest with another food to see if its just an intolerance to the specific test food), white onion for fructan-onion testing, garlic for fructan-garlic testing, avocado for sorbitol testing, cauliflower for mannitol testing, chickpeas for oligosaccharide testing, and mango for fructose testing. For the pasta, brussel sprouts, onion, garlic, and cauliflower I made sure to cook the foods as cooked foods aid in digestion and would therefore be better tolerated.
Testing Examples
If you don't have access to the Monash University app here are the portions I tested with the foods I chose:
Fructan grain - wheat bread
Day 1: 1 slice whole wheat bread
Day 2: 1.5 slice whole wheat bread
Day 3: 2 slices whole wheat bread
Fructan grain - pasta
Day 1: 2/3 cup (3oz) uncooked pasta
Day 2: 1 cup (5oz) uncooked pasta
Day 3: 1.5 cup (8oz) uncooked pasta
Fructan fruit/veggie - raisins
Day 1: 1.5 tbsp (1oz) raisins
Day 2: 2 tbsp (1oz) raisins
Day 3: 3 tbsp (1oz) raisins
Fructan fruit/veggie - brussel sprouts
Day 1: 3 sprouts (2oz)
Day 2: 4 sprouts (3oz)
Day 3: 5 sprouts (3oz)
Fructan onion - white onion
Day 1: 1/8 onion (0oz)
Day 2: 1/4 onion (1oz)
Day 3: 1/2 onion (2oz)
Fructan garlic - garlic
Day 1: 1/4 clove (0oz)
Day 2: 1/2 clove (0oz)
Day 3: 1 clove (0oz)
Sorbitol - avocado
Day 1: 1/4 small avocado (1oz)
Day 2: 1/2 small avocado (3oz)
Day 3: 3/4 medium avocado (4oz)
Mannitol - cauliflower
Day 1: 2 small florets (1oz)
Day 2: 4 small florets (1 oz)
Day 3: 8 small florets (2oz)
Oligosaccharides - chickpeas (canned and rinsed)
Day 1: 1/2 cup chickpeas (3oz)
Day 2: 2/3 cup chickpeas (4oz)
Day 3: 1 cup chickpeas (6oz)
Fructose - mango
Day 1: 1/4 mango (2oz)
Day 2: 1/2 mango (4oz)
Day 3: 1 mango (7oz)
*for the sizes of the foods you are testing, choose the size you would typically eat and stick with the portion sizes of that food. For example, maybe you regularly buy extra large onions. If so, test 1/8 of that onion to see your tolerance. I often stressed about the sizes of the foods I was testing but try to stick to the most typical sizes you would purchase and eat.
Symptoms - What to look out for
The process of reintroducing is done to allow more variety and freedom into your diet. For this reason, when testing you want to look out for symptoms which are extreme, painful, out of the ordinary, disrupting, or excessively uncomfortable. For me this meant a test went awry if I had painful trapped gas which lasted 45 min or more, diarrhea, very excessive gas, painful spasms, or extreme bloating. If I had mild gas, an extra bowel movement or two with normal poop (i.e. not diarrhea or very solid poop, an easily passable poop), or a small bloat, I did not discount these tests as having gone bad. This just means these foods may need to be a little more limited in my diet, however not cut out completely.
This is very important for your gut health! The FODMAPs we all cut out from our diets to ease our IBS symptoms are all prebiotics. This means these fruits and veggies feed our good gut bacteria and help them flourish. By restricting these foods we are not nourishing our gut bacteria and creating a healthy microbiome. The more diversity of plants you can get in your diet, the better resilience you will gain against these hard to digest foods, and the better your health will be. For this reason, if possible you do not want to fully restrict any of the plant FODMAPs in your modified low FODMAP diet post reintroduction to allow more diversity back into your gut.
If you have IBS-C or IBS-D/C (the constipation version of IBS) you may have constipation rather than diarrhea as a symptom. Personally I have IBS-D and therefore my extreme symptom was diarrhea.
What to Avoid on Test Days
I found that those 3 days of my test week, typically Monday - Wednesday, were very hard for me. I felt very restricted in my diet, especially after trying to avoid restricting post disordered eating. However, I was also really committed to finishing the low FODMAP diet and getting a full picture of what foods do and do not work for me. To me, understanding my body and what it can handle was power, and I felt that enduring a little restriction for more power over my eating and diet was worth it. If you have a similar experience with food restriction, speak with a dietician or healthcare professional about it to assist you to avoid any disordered eating thoughts or habits.
During the entire testing process you are meant to remain on a strict low FODMAP diet as you did in the elimination portion. The only difference is the 3 days where you are introducing a high FODMAP food into your diet to see how you tolerate it. Keeping a low FODMAP diet throughout testing allows for a clear baseline to compare your symptoms to.
I have a couple tips for testing days:
Avoid eating a meal that has too many foods of one FODMAP group: this is called FODMAP stacking. Although different foods may have low FODMAP portions you can eat during the elimination phase, if you eat multiple servings of those foods and they are in the same group, you may be combining the FODMAPs and creating a high FODMAP meal. For example, If you have 1/3 cup zucchini, 3/4 cup broccoli, and 2 brussel sprouts in one meal, it may seem as though you are consuming all low FODMAP, but the combination of all those fructans at once may cause symptoms!
Avoid eating big meals, or too often: with testing its best if you eat smaller meals more often. This means a meal every 3-4 hours. Allowing 3-4 hours between meals means you help eliminate the risk of FODMAP stacking if you are to eat from the same FODMAP group because you have time to fully digest. This also helps prevent symptoms which may confound your results because eating too much at once can cause bloating and discomfort.
Avoid choosing new meals that you don't know if you tolerate well: take time in your elimination phase to experiment with those low FODMAP ingredients and understand which ones you tolerate best. Doing this will allow you to eat meals during testing which you can be sure do not cause you symptoms. This allows for clearer results and a better understanding of your tolerances. Personally, brown rice pasta with a simple tomato sauce, a vegan grilled cheese with sourdough bread and Violife cheddar cheese, oatmeal with nut butter, seeds and a green banana, tomato cucumber Israeli salad, and almond milk yogurt with homemade low FODMAP granola were all staples for me during testing. If you need more recipe ideas for low FODMAP meals feel free to DM me on instagram (@ibs.strong) or leave a comment under this post!
The Washout Period
The washout period of reintroduction is the four days after your 3 days of testing where you continue to eat completely low FODMAP, without reintroducing foods you may have discovered worked for you during testing. This is used to allow your body to get rid of the FODMAPs you consumed during testing. This is important for avoiding FODMAP interactions between different carbohydrate groups. For example, your body may tolerate sorbitol alone, but in combination with fructose, you may have an issue. For this reason, say you tested sorbitol Monday - Wednesday, and you previously tested fructose and discovered you tolerated it well, if you consume the fructose in those four days (Thursday-Sunday) where your body hasn't fully gotten rid of the sorbitol, you may have symptoms and not understand where they are coming from. It may also interfere with the next test you are doing that upcoming Monday. The washout period is very important and the reason why we continue eating strict low FODMAP even when we learn about foods we tolerate well.
I apologize for the length of this post, but I hope it was helpful and helped curb some anxiety you may have regarding FODMAP reintroduction. If you have remaining questions about any of the topics I covered, leave a comment and I will get back to you, and hopefully add it to the post so everyone can see!