Vegetarianism + Digestion: How to Stop the Rumbles

Shift to a more plant-based diet gradually, and most likely your body will adjust just fine to a vegetarian or vegan diet.

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New vegetarians and vegans who enthusiastically pile their plates with whole grains and vegetables may be dismayed to experience bloating, gas, or other stomach upsets—and mistakenly think they have a food allergy or that this diet isn’t for them. Not so! Shift to a more plant-based diet gradually, and most likely your body will adjust just fine to a vegetarian or vegan diet.

Even if you love whole foods, go easy at first. “No pigging out,” says Mindy Hermann, RDN, a New York-based dietitian. Instead, monitor what you eat and how your
body tolerates each food. Still, certain cooking and food choices can make digestion easer. Here are four main food groups and the common digestion problems they can cause in vegetarians or vegans—as well as some simple solutions.


Problem: Legumes can cause stomach discomfort and gas. The culprit? The carbohydrates, says Hermann: “They go undigested into the large intestines where they’re finally broken down—and the byproduct of that process is gas.”

Solution: Make sure beans are well cooked. “Beans don’t do any good cooked al dente,” says Hermann. “They need to be soft on the inside. The firmer they are, the harder they are to digest.”

Rinsing beans after soaking but before cooking also helps by getting rid of some of the non-digestible elements. During cooking, skim off any foam that forms. If you soak beans overnight, rinse them well before cooking. If you’re using canned beans, empty the liquid and rinse the beans before using them. Beano or other over-the-counter preparations can help prevent gas problems. Probiotics containing Bifidobacterium and Lactobacillus may also help reduce gas and bloating, according to a Harvard Medical School special report on food allergies, intolerance, and sensitivity.

Related: Should I Take Probiotics for an Upset Stomach?

Fruits & Vegetables

Problem: “The acid in citrus fruit can cause stomach trouble,” says Hermann, as can melons, apples, and other fruits. Meanwhile, vegetables like broccoli and cauliflower can also cause gas.

Solution: Eat fruit with other food, and make sure the fruit is ripe. “Less-ripe fruit contains indigestible carbohydrates,” says Hermann. And watch out for dried fruit—it can be a laxative, she adds. Limit your portions and introduce dried fruit into your diet slowly, paying attention to your gut’s tolerance. As for those nutrition-packed but gas-producing veggies? Keep them in your diet but combine them with other less gas-creating vegetables.

Related: Immunity-Boosting, Cold-fighting Cleanse Basics

Whole Grains

Problem: Eating a lot of whole grains can cause abdominal discomfort because their outer coatings can be hard to digest, says Hermann.

Solution: Introduce whole grains in small portions and start with a gentle grain like brown rice, which is not all that high in fiber, as opposed to, say, wheat berries. Cook whole grains well, and also try introducing whole wheat as flour in baked products. “When it’s ground up, whole wheat is easier to digest,” Hermann says.


Problem: Many vegetarians lean heavily on dairy products, but some find that as they age, their digestive systems are less able to handle lactose, (a form of sugar in dairy products) because they have less lactase—the enzyme in our guts that breaks down lactose. When lactose can’t be broken down in the intestines, it goes to the colon where bacteria do the job, causing gas, bloating, and diarrhea, according to a Harvard Medical School special report.

Solution: Taking Lactaid or a similar product will break down the lactose. Also, look for products that are lactose-free—they are pretreated with enzymes that break down lactose.
Yogurt, cheese, and sour cream don’t contain as much lactose, so they may cause no problems, according to the Harvard special report. “And many brands of yogurt contain probiotic bacteria that can improve your digestive tract,” says Hermann, including its ability to break down lactose.