9 ways to eat more fiber (while minimizing bloating)

In the world of nutrition, fiber is poised to become “the new protein” — the thing everyone is trying to get more of in their diet. It’s like everyone suddenly realized fiber helps you feel full and keeps you regular. And that’s not all: “We now know that many types of fiber also act as food for beneficial gut microbes,” explains Simone Venner, RDN, a registered dietitian nutritionist in London specializing in digestive health. “When we consume fiber, the bacteria in the large intestine ferment it and produce compounds that help nourish the cells lining the colon, support the gut barrier, and regulate inflammation.” With at least 70% of the body’s immune cells located in the gut, you can see how a diverse microbiome fed by a fiber-rich diet is crucial for overall health. 

Of course, there’s a catch: The fermentation process that makes all those benefits possible can also cause bloating, painful and annoying gas, and constipation. This is especially true when you go full-throttle and suddenly eat way more fiber than you used to. (The irony!) But there are ways to get the good stuff while minimizing the gas. Here’s how:

The first rule of fiber club is: You do not join overnight. “The key is to think of the gut microbiome like a muscle in the gym: It needs to be trained,” says Venner. “If someone jumps suddenly from a low-fiber diet to a very high-fiber one, bloating is more likely because the gut bacteria aren’t used to it. Increasing fiber gradually gives the gut time to adjust.” So if you want to get the recommended 25 to 38 grams of fiber per day and are currently eating a lot less, increase your intake by about 3 to 5 grams (about the amount in one apple or a serving of oatmeal) every few days.

At the same time that you up your fiber intake, do the same with water. “Fiber needs fluid to move comfortably through the gut,” says Venner. This is because fiber absorbs water in your digestive tract like a sponge, plumping up into nice, soft-yet-bulky stool. If there’s not enough water in your system, all that fiber turns the stool hard and dry and it’s “hello constipation.”

Consuming a large amount of fiber all at once is more likely to cause tummy trouble, says Razan Hallak, RDN, a registered dietitian nutritionist at The Ohio State Wexner Medical Center. So don’t try to eat 20 grams in a single sitting. Instead, Hallak advises spreading your fiber-containing foods evenly throughout the day — 6 to 10 grams at breakfast, lunch, dinner, and 3 to 5 grams in your snacks — rather than packing them all into one meal.

Exercise is extra important when you’re bumping up your fiber intake. “Regular physical activity helps the bowels function smoothly and can reduce the risk of constipation, thus reducing bloating,” explains Venner. Walking, swimming, or another moderate aerobic exercise three to four times a week is a good goal to benefit digestion.

Different foods contain different kinds of fiber, which have differing effects on your digestion. For example, soluble fiber (in foods like oats and beans) draws in water to stool and slows digestion. And insoluble fiber (in foods like whole grains) adds bulk to stool and speeds up digestion. Get a mix of both kinds by eating a wide variety of fiber-containing foods — including whole grains, fruits, vegetables, nuts, seeds, and legumes — rather than hitting any one category too hard.

Choosing softer fiber-rich foods to start can help reduce the strain as your gut adjusts to more fiber. “Generally, raw fruits and vegetables with roughage are harder to digest,” says Hallak. If you notice bloating, make it easier on your body by cooking veggies and beans or going with soft foods like oatmeal, bananas, melons, avocado, bean dip, hummus, or peanut butter instead of whole fruits, beans, or nuts.

If your bloating is really bad after eating fiber, don’t ignore it. “For many people, a small amount of fullness after a fiber-rich meal is simply a sign that the gut microbiome is doing its job, but in people with IBS (irritable bowel syndrome) or a more sensitive gut, this gas production can feel more uncomfortable,” says Venner. If you see a link between eating fiber and moderate-to-severe digestive issues, reach out to your healthcare provider. “Some individuals lack enzymes that help break down carbohydrates found in some fiber-rich foods, leading to worsening of their GI symptoms,” says Hallak. Your doctor will be able to help you figure out what’s going on and how to handle it.

Certain foods produce more intestinal gas than others because they contain fermentable carbohydrates, often called FODMAPs (which stands for the syllable-heavy “fermentable oligosaccharides, disaccharides, monosaccharides, and polyols”). People with stomach conditions like irritable bowel syndrome might find relief from bloating and other symptoms by eating less high-FODMAP foods like onions, garlic, beans, lentils, and some mushrooms. Instead, prioritize foods such as oats, quinoa, potatoes, cucumbers, or strawberries, which are full of fiber but tend to be gentler on the belly during GI flare-ups.

There’s no real upper limit for safety when it comes to fiber, but you might want to be cautious when adding fiber pills and powders to your day since they can deliver a major dose all at once. “Extremely high fiber intakes, particularly from supplements, without adequate fluid may cause gastrointestinal symptoms in some people,” cautions Venner. How much fiber you can tolerate before you bloat varies from person to person, but make sure you don’t add too much too quickly with supplements. There is no exact recommendation for how much fiber you should get from supplements, but track your fiber intake for a few days (you can see this in the app along with other macros) to see what you average, then gradually fill in the gap with other fiber-filled foods. If you still are not reaching your fiber goals, talk to your healthcare professional to see if a fiber supplement may be a good fit for you.

Fiber is one of the most powerful tools we have for your gut, immune system, and overall health — but upping your intake too quickly can be hard on your GI tract and cause bloating. Increase your intake gradually, drink plenty of water, exercise, and eat a variety of fiber-rich foods spread throughout the day, and you’re more likely to get the benefits while minimizing the bloat. If you do notice more severe GI issues with higher fiber intake, bring it up with your healthcare provider to make sure there’s nothing else going on.