Low FODMAP diets have been clinically proven to reduce or eliminate the symptoms of IBS in about 70% of patients. It is the standard now for establishing a basis for determining which FODMAP foods, or combinations of food, are creating the symptoms in each individual.
First, nearly all FODMAP foods are eliminated for a period of several weeks and then slowly reintroduced into the diet one at a time to determine which ones are causing the issues.
Having worked on several IBS/Crohns drugs, this diet is the front line approach these days before other therapies are employed.