Increasing Your Fiber Intake Without the Side Effects

If you’ve tried adding more fiber to your diet after eating low carb and ended up bloated, gassy, or just plain uncomfortable—you’re not alone. It’s a common experience, and it’s usually not because fiber is the problem, it’s because of how quickly it’s added.

In our recent article on the new Food Guide Pyramid, we broke down why fiber is one of the most under-consumed nutrients in the U.S. and why that matters. Most adults need 25–34 grams per day, but the average intake is closer to 15 grams. That gap matters. Fiber plays a key role in digestion, keeps blood sugar steady, improves heart health, and keeps you feeling fuller longer.

The good news?  You don’t have to choose between getting enough fiber and feeling good. With a gradual, step-by-step approach, you can increase your intake without the uncomfortable side effects.

Step 1: Start with Soluble Fiber

Think of soluble fiber as the “gentle” place to start. Soluble fiber forms a gel in your gut, helping slow digestion, stabilize blood sugar, and support cholesterol levels.

Begin by adding one source per meal (about ½ cup), then gradually increase your intake as your body adjusts.

Great options include:

• Apples, oranges, pears, berries
• Peas, avocado, sweet potato, carrots, turnips
• Sprouted or pressure-cooked oats
• Soaked or pressure-cooked beans
• Lighter leafy greens

If you’re tolerating this well (no major bloating or discomfort), you can increase to two sources per meal and add fiber-rich snacks.

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Step 2: Add Insoluble Fiber

Once your body is handling soluble fiber well, it’s time to layer in insoluble fiber. As its name implies, insoluble fiber does not dissolve in water and remains mostly intact, acting like a “broom” as it moves through the GI Tract. Adequate water intake is important when increasing this type of fiber to prevent cramping, constipation or other uncomfortable side effects.

Start with small portions (about ½ cup) and build gradually.

Examples include:

• Zucchini, broccoli, cauliflower, cabbage
• Dark leafy greens
• Blackberries, raspberries
• Flax seeds, chia seeds
• Whole grains (quinoa, brown rice, millet, etc.)

Blend in these foods into smoothies can make them easier to digest while your body adapts to this new fiber source.

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Step 3: Individualize Your Fiber Intake Based on Carbohydrate Intake

Your fiber plan should match your lifestyle, not the other way around.

If you prefer to stay lower carb, you can still meet your fiber needs by focusing on non-starchy vegetables and other lower-carb options.

Lower-carb, fiber-rich foods:

• Salad greens, artichokes, mushrooms
• Onions, peppers, radishes, tomatoes
• Zucchini, water chestnuts

If you’re open to increasing your carb intake, you can gradually add starchier, fiber-rich foods.

Examples include:

• Potatoes, sweet potatoes, yams
• Corn, peas
• Squash, pumpkin, cassava, taro

Find a balance that feels sustainable and helps you move toward your fiber target.

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Additional Tips for Success

• Hydrate: Fiber works best when you’re well-hydrated.
• Keep moving: Regular movement supports digestion.
• Use supplements if needed: If you’re struggling with constipation, a fiber supplement can help bridge the gap. Start with 1 teaspoon of psyllium husk per day, then slowly increase every few days as tolerated (up to 1 tablespoon 1–2 times daily if needed). Products like Citrucel can also help, especially for adding insoluble fiber. Always pair with plenty of water.
• Get support: If symptoms persist, check in with your provider. A Registered Dietitian or Health Coach can help you personalize your plan.

The Bottom Line

Most people aren’t getting enough fiber—but more isn’t better when you add it too quickly.

Start with soluble fiber, layer in insoluble fiber gradually, and adjust based on your carb preferences. When you take a step-by-step approach, you can support digestion, improve metabolic health, and feel better overall—without the uncomfortable side effects.

Curious what a day of high fiber eats might look like? Click here to see an example.  

Need more ideas? Check out this list of high-fiber foods and their fiber content to get you started.

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