Day: December 2, 2025

• Most people don’t eat enough fiber, which supports heart health and lowers the risk of colon cancer.
• However, a dietitian warned that eating too much fiber too soon can cause digestive distress.
• She shared tips on how to gradually increase your fiber intake until your body adjusts.

Most Americans don’t eat enough fiber. As a result, they miss out on its many benefits, including supporting heart and gut health, lowering cholesterol, managing weight, and reducing the risk of colon cancer.

If you feel tempted to stock up on soluble fiber — say, by adding beans to every meal — you might want to take your foot off the gas. Literally.

“Many people can experience gas or bloating when they increase fiber too quickly,” Michelle Routhenstein, a preventive cardiology dietitian, told Business Insider. Eating too much fiber too quickly can cause more intense symptoms of gastrointestinal distress, like constipation, abdominal pain, and nausea.

Routhenstein works with her clients to gradually introduce more fiber to their diets until they reach their daily goal — 25 grams for women and 38 grams for men.

Here are a few of Routhenstein’s tips on how to sneak in more fiber — without any discouraging stomach pains.

Start with small changes

Routhenstein recommends starting by adding fiber to one meal a day at a time.

“Choose foods you already enjoy and tolerate well, then build from there,” she said.

If you’re very new to eating fiber (or have a history of it causing gassiness and bloating), some easy additions include:

• Sprinkling a teaspoon or two of ground flax or chia seeds on your morning yogurt or oats, building up as you go
• Mixing ¼ or ½ of a cup of beans or lentils into a stew
• Swapping fries with cooked vegetables, which are gentler on digestion than raw vegetables

Eventually, the goal is to ramp up your fiber intake — like adding fresh fruit to that morning yogurt, snacking on raw carrots, and having at least two servings of vegetables for dinner.

Stay hydrated and move around

Besides watching your diet, Routhenstein said there are a few other ways to avoid fiber-related bloating.

Staying hydrated and drinking plenty of water aids digestion and helps prevent constipation.

Exercise can also help. Routhenstein recommended easy walks after meals, which also improves digestion.

It can take a few weeks to 6 months to adjust

How long it takes for your body to get used to your daily recommended fiber intake all depends on where you start, Routhenstein said.

If you’re someone who already eats some fiber, the transition can take a few weeks with a steady increase of salads and fruit.

But if you almost never eat fiber, your gut microbiome is likely less equipped to handle a sudden fiber introduction, she said. “In those cases, it can take six months or more to rebuild the microbial diversity needed to comfortably tolerate higher fiber levels.”

No matter where you begin, the key is to go slow and not give up.

“The focus isn’t on racing to the ‘end goal,’” she said, “but on making small, consistent daily adjustments that support long-term digestive health and a sustainable heart-healthy lifestyle.”