Gut Health Experts Say These Are the Foods Making You Gassy

For many people, gas and bloating can be an unpleasant if unavoidable side effect of eating the foods they love. But the root cause of gas is actually a bit more complicated than you might think, while the foods that can make you gassy are doing so not because of how you are digesting them, but for a different reason.

Meet the experts: Lavanya Kethamukkala, R.D.N., C.L.T., L.D.N., a registered dietitian nutritionist and founder of Nourishing Expert in Apex, N.C.; Rudolph Bedford, M.D., a gastroenterologist at Providence Saint John’s Health Center in Santa Monica, CA.

Here, digestive health experts explain the real cause of gas, plus share the top foods that can cause gas and bloating.

“Gas is a normal part of digestion,” says Lavanya Kethamukkala, R.D.N., C.L.T., L.D.N., a registered dietitian nutritionist and founder of Nourishing Expert in Apex, N.C. “As beneficial gut bacteria ferment undigested carbohydrates in the colon, they naturally produce gases such as hydrogen, methane, and carbon dioxide,” which are then expelled from the body. That’s right: It’s not technically your body producing the gas, but the bacteria that make up your microbiome. “You have over 100 trillion bacteria, fungi, and viruses living in your small intestine and colon,” says Rudolph Bedford, M.D., a gastroenterologist at Providence Saint John’s Health Center in Santa Monica, CA. He explains that the amount of bacteria you have in your microbiome, the different types present and in what ratios, and how effectively they are digesting the foods you are consuming all contribute to how much gas is produced.

Dr. Bedford says that the types of food you eat are the key predictor of how much gas you might experience, but it’s not the only factor to consider. “Eating too quickly, constipation, stress, food intolerances, IBS, carbonated beverages, swallowing excess air, and certain medications can all contribute to excess gas and bloating,” says Kethamukkala. While some of these are more difficult to control than others, eating the right foods when you’re feeling extra bloated or don’t want to experience gas is the best thing you can do to try to control how much gas your microbiome is producing.

Once again, whether or not you experience gas after eating depends on how the bacteria in your gut digest the foods you choose. “It’s the bacteria that are producing the gas as their by-product,” says Dr. Bedford. So, what foods cause the most gas? Here are the biggest ones.

Beans and lentils

“These are rich in oligosaccharides, a fermentable carbohydrate that reaches the colon undigested, where gut bacteria ferment it and produce gas,” explains Kethamukkala. “Despite this, they’re among the healthiest sources of fiber and plant protein.” If you slowly increase your intake until you’re eating beans every day, you’ll be less likely to experience gas and instead will simply reap the benefits of these nutrient-dense plant foods.

Cruciferous vegetables

As is the case with beans and lentils, gradually increasing your intake of cruciferous veggies like broccoli, cauliflower, cabbage, and Brussels sprouts until you’re eating them regularly will make it less likely that you become super gassy or bloated. Nonetheless, it is possible. “They contain raffinose and sulfur-containing compounds that are fermented by gut bacteria, increasing gas production,” Kethamukkala says. “But these veggies also provide fiber, antioxidants, and other beneficial plant compounds.”

Dairy products

According to the National Library of Medicine, about 30 million American adults (or 11% of the population) have some degree of lactose intolerance, the inability to digest lactose, a sugar found in dairy. “Many of us become lactose intolerant as we get older because we’re no longer producing lactase,” the enzyme that breaks down lactose, Dr. Bedford explains. If you fall into this group, you’ll likely experience some gas or other GI issues from eating or drinking dairy products.

Processed, artificially sweetened foods

Sugar-free foods that are sweetened with products like sorbitol, mannitol, xylitol, and erythritol may cause gas and bloating. “The bacteria in our gut can’t digest these sweeteners and they are poorly absorbed,” says Dr. Bedford, which can lead to gas.

Carbonated beverages

“Carbon dioxide from fizzy drinks can become trapped in the digestive tract, contributing to bloating, belching, and feelings of fullness,” says Kethamukkala. If you’re drinking a diet soda or energy drink that’s artificially sweetened, you may experience double the bloating effects.

Every person is different and the foods that cause uncomfortable gas or bloating for some may not do the same for others. As mentioned above, someone who eats beans or broccoli on a daily basis may not experience as much gas from these foods as someone who doesn’t eat them regularly. If you’re concerned about what feels like excessive gas or bloating, try to track what you’re eating, consider taking steps to banish your gas and bloating, and don’t hesitate to give your doctor a call if you need to.