FODMAPs describe a collection of short-chain carbohydrates found in many common foods. FODMAPs stands for Fermentable Oligo-, Di- and Mono-saccharides, and Polyols.
Consuming foods high in FODMAPs results in an increased volume of liquid and gas in the small and large intestine, resulting in distention and symptoms such as abdominal pain and gas and bloating. Following a low FODMAP diet should result in a decrease in digestive symptoms. There is a cumulative effect of these foods on symptoms. In other words, eating foods with varying FODMAP values at the same time will add up, resulting in symptoms that you might not experience if you ate the food in isolation.