Disclaimer: I am not a dietitian and you should definitely meet with one before embarking on any kind of extreme change to your diet!
IBS stands for “irritable bowel syndrome” and in my completely unprofessional medical opinion it basically means that your digestive system feels like shit most of the time and no one can really tell you exactly why. Kind of like an acknowledgement from the doctor that they believe you are suffering, so they want to give you a diagnosis, but they can’t really explain what it is that is wrong. Over the years I’ve heard a lot of things, that maybe it is triggered by a virus, that maybe you just have more sensitive nerve endings in the gut, etc. etc. But the one thing that has shown positive results in about 75-80% of IBS patients is the low FODMAP diet.
The low FODMAP diet was developed by Australian researchers at Monash University, and the acronym stands for Fermentable Oligosaccharides (found in garlic 😦 , onion :(, wheat :(, and beans) Disaccharides (lactose) Monosaccharides (fructose found in some fruits, honey, agave etc) And Polyols (sugar alcohols found in some fruits, veggies, mushrooms :(, and in fake sugar substitutes). The idea is that these types of sugars are poorly absorbed in IBS guts, therefore sit in the gut longer and ferment, causing gas and bloating and disrupting the water balance in your intestines. But the extent to which each of these sugars affects you is different from patient to patient, so the common practice is first to cut them all out altogether in an *elimination phase* for several weeks-months until symptoms disappear, and then test them each one by one in controlled portions during the *reintroduction phase* thereafter.
There are a lot of sites online with sometimes conflicting lists and information on what to eat or not to eat, so the best is to follow instructions from a dietitian or refer directly to the resources from Monash University, like their app.