It was developed by Sue Shepherd, an Australian nutritionist and dietitian. The name comes from an acronym of foods she believes may cause problems for people suffering from IBS: fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. That covers a huge variety of foods, from honey and apples to artichokes and ice cream to baked beans and cherries, and many, many more. The hardest part of the diet, Ms. Arnold said, is finding foods that don’t have any of the proscribed ingredients in them. The first time she went to a dietitian at the University of Michigan who specializes in the disorder and the low FODMAP diet, the dietitian told her to buy a snack food that was free from all FODMAPs. “I went over to a grocery store and I stood there and I was nearly in tears looking at all of those snack foods I couldn’t have. I finally found a Quaker rice cake with chips,” she said. Only the kettle corn variety of rice cakes met the criteria for the diet. Because of her IBS combined with her hypoglycemia (low blood sugar), Ms. Arnold has learned that she must eat throughout the day.