Milk and high-lactose dairy foodsZoonar/Thinkstock
A key component to keeping your tummy happy is the avoidance of FODMAPs, or rapidly fermentable carbohydrates that can aggravate your gut. Some people aren’t sensitive to any FODMAPs, some experience symptoms after eating only certain ones, and other people develop gradually worsening effects with each exposure. Lactose, found in all animal milks, is the best known FODMAP. Lactose is broken down in the small intestine by an enzyme called lactase. Our bodies produce less lactase as we get older (since its main purpose is to help babies digest breast milk), which means dairy foods that contain lactose can torment our tummies over time even if they didn’t before.
Found in: milk, regular (non-Greek) yogurt, soft cheeses, dairy-based desserts.
Excess fructose (in apples, honey, asparagus)iStockphoto/Thinkstock
Foods with a lot of fructose (another FODMAP) compared with glucose can contribute to gas, bloating, and diarrhea. A 2008 study in the Journal of Clinical Gastroenterology found that patients with IBS who followed a non-fructose diet had fewer symptoms.
Found in: certain fruits (apples, mangoes, watermelons), certain vegetables (asparagus, sugar snap peas), sweeteners (high-fructose corn syrup, agave nectar, honey).
Garlic, onions, and high-fiber cousinsHemera/Thinkstock
The body’s inability to digest a kind of fiber, called fructan, in these foods can cause flatulence. This fiber (another FODMAP) seems to cause more symptoms than some other kinds, but that may simply be because we eat so much of it.
Found in: grains (barley, wheat), vegetables (artichokes, onions, garlic), legumes (black beans, kidney beans, soybeans), additives (inulin).