FODMAP reintroduction schedule

Updated October 4, 2026 by Kamal Nasir

A FODMAP reintroduction schedule tests one FODMAP at a time: each challenge runs over 3 days with a bigger serve each day, then you take a 2 to 3 day break on low FODMAP foods before the next one. Following Monash University's method, 6 challenges with 3 day breaks take 33 days and 8 take 45, and Monash says the whole phase takes most people around 6 to 8 weeks. Pick a start date and put your challenges in order below to get the dates, a printable record sheet and calendar events.

General information, not medical advice. How these guides are made.

How the schedule works

Monash University's method tests one FODMAP at a time. Each challenge runs over 3 days: a moderate serve on day 1, a high serve on day 2, and a higher serve or your usual portion on day 3, eaten at about the same time each day. You stay on your Step 1 low FODMAP diet throughout, so the challenge food is the only change.

After each challenge comes a break of 2 to 3 days on low FODMAP foods, or longer until symptoms settle, and there is no break after the last one. That makes the plan 3 days per challenge plus one break between each pair: 6 challenges with 3 day breaks take 33 days, 6 with 2 day breaks take 28, and 8 with 3 day breaks take 45. Monash says the whole phase takes most people around 6 to 8 weeks.

The planner counts in calendar days, so a clock change cannot move a date, and it shows every date in your own language and date format.

IBS Tracker Food Diary: Fennel

IBS food diary and symptom tracker

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Which order to test in

Monash says there is no particular rule. Some people start with a FODMAP they expect to tolerate, to build confidence. Some start with one they think they do not tolerate, for a clear answer sooner. Others start with the FODMAP in a staple food, for example fructans in wheat pasta, so they know early whether it can stay in their everyday diet.

Monash groups FODMAPs as fructans and GOS, lactose, fructose, and the polyols sorbitol and mannitol, and tests each one separately because tolerance to each can differ. The planner starts with fructose, lactose, sorbitol, mannitol, fructans and GOS only as a list to edit. Reorder it, rename a row, or add one to test a FODMAP in more than one food, such as fructans in garlic and fructans in onion, up to 12 challenges.

What to record each day

Print the schedule to get one row per day with an empty column for each of these. Fill in the break days too, so you and your dietitian can see whether symptoms had settled before the next challenge began.

• The food and the portion you ate
• The time you ate it
• Each symptom, with its time and how bad it was
• Your bowel movements
• Your stress level, which the Monash diary also records

When to pause

Monash advises waiting until your symptoms are well controlled before you begin each challenge, and taking a 2 to 3 day break between challenges, or longer until symptoms settle. If a break ends and you are not back to your usual, press "Symptoms not settled? Add a break day here" on that break. It adds one low FODMAP day and moves every later date one day later. Press it as often as you need, then print the schedule or download the calendar file again.

The calendar events keep the same identity when you add a day, so importing the new file into the same calendar moves the events rather than adding a second set in most calendar apps. Note anything unusual on a challenge day, such as an illness or a stressful event, for your dietitian to weigh.

Safety first

The FODMAP diet is meant for people with medically diagnosed IBS, and Monash says it should be followed under the guidance of a dietitian. Reintroduction comes after 2 to 6 weeks on the Step 1 low FODMAP diet, and only if symptoms improved. If they did not, Monash says your IBS may not be sensitive to FODMAPs and other therapies are worth considering with your doctor.

This planner only sets dates. It does not choose foods or portions, and it does not interpret your results. Monash's own app suggests challenge foods and quantities for each FODMAP, and a dietitian can read your responses with you. Nothing you type into the planner is sent anywhere; the schedule is worked out in your browser.

Planning reintroduction in Fennel

Fennel, an IBS food diary for iPhone, has a guided reintroduction program that schedules challenge days and rest days, records what happened on each, and drafts a reading you can accept or overrule. Phase lengths appear as ranges because its sources state them as ranges. The program is part of Fennel Pro.

Day to day, Fennel logs a meal in seconds, a symptom in three taps and stool in two, and reports how often symptoms followed each food and FODMAP group, with the days and counts behind every reading. It never labels a food good or bad. It has no account, no sign in and no server, and the diary stays on the phone you logged it on. Fennel is a diary and a statistics tool: it does not diagnose, treat or advise, and it is not a substitute for your doctor or a registered dietitian.

Questions people ask

Related

• How to Keep a Food Diary for IBS: What to Record
• How to Reintroduce FODMAPs: The Reintroduction Phase
• IBS Tracker Food Diary: Fennel