The Possible Reason Onions Give You Indigestion

When you're young, you can eat and drink anything and everything. Your metabolism seems to burn calories right off and whatever you eat or drink only bothers you going in or coming out. Everything in between works like a well-oiled machine. When you get a bit older, though, things seem to slow down and that machine begins to give a little more feedback than it used to. By understanding what you're putting into your body, you may be able to ease some of that stomach trouble.

Indigestion due to onions might be caused by the fermentable oligosaccharides, disaccharides, monosaccharides, and polyols — known as FODMAPs — that are found in onions and other foods. FODMAPs are basically just particular forms of sugars and other carbohydrates that are more difficult for stomach acid to break down, which results in them fermenting in the stomach and longer digestion, per Livestrong.

According to University of Michigan Health, as people age, their stomachs produce less acid and thus can take longer to break down food. As FODMAPs ferment in the stomach, they can produce gas build-up that can lead to bloating and indigestion as the stomach struggles to break down the food. Besides pretty much every type of onion, Healthline also identifies wheat and wheat products (like breads, pastas, and cereal), garlic, and artichokes as other foods high in FODMAPs.

FODMAPs can also cause instances of acid reflux, per Vanguard Gastroenterology. Gasses that form in the stomach can lead to belching and other reactions that can cause stomach acid to backflow into the esophagus, which leads to heartburn and even more discomfort. Cooking your foods that are high in FODMAPs has been known to alleviate some of the causes, as cooked food is easier for your stomach to break down. A guide for cooking different types of onions can come in handy if the pungent vegetables are giving you problems.