Why You Need More Fiber in Your Diet (and 9 Easy Ways to Get More)

Amy Corcoran, MS, RDN

You’ve probably heard that fiber is great for digestion, but did you know it’s also essential for heart health, blood sugar control, and a healthy gut?

Fiber (one of my favorite nutrients!) is found in plants like fruits, veggies, whole grains, and legumes. It’s been getting the spotlight recently, and for good reason! The only problem? Most of us still aren’t getting enough of it.

Let’s break down why fiber is such a big deal and how to sneak more into your diet.

What Is Fiber?

Fiber is a type of carbohydrate that your body can’t digest. Unlike sugars and starches, which your body breaks down for energy, fiber makes its way through your digestive system mostly unchanged. There are two main types of fiber:

Soluble Fiber

This fiber dissolves in water, turning into a gel that helps lower cholesterol and stabilize blood sugar levels. When soluble fiber reaches your colon, it’s fermented by gut bacteria. I know “fermenting” sounds a little weird, but this is where the magic happens

When soluble fiber gets fermented by your gut bacteria, they produce short-chain fatty acids (SCFAs) like butyrate, acetate, and propionate. These SCFAs nourish your gut lining, help reduce inflammation, and protect against diseases.

Examples of Soluble Fiber:

Beta-glucan: found in oats and barley
Pectins and gums: found in apples and citrus
Inulin: found in garlic, onions, and asparagus

Insoluble Fiber

This fiber doesn’t dissolve in water; instead, it absorbs water, which helps add bulk to your stool. This bulk makes it easier for your stool to move through the digestive system. Insoluble fiber is the type of fiber you need to stay regular.

Examples of Insoluble Fiber:

Cellulose: found in the outer layers of vegetables, fruits, and grains
Hemicelluloses: found in whole grains and seeds
Lignin: found in flaxseeds, whole grains, and vegetables

Resistant Starch

Okay, this one technically isn’t a fiber, but it deserves a shout-out. Resistant starch behaves like fiber, resisting digestion in the small intestine and getting fermented in the colon, feeding your good gut bacteria that produce those SCFAs.

Examples of Resistant Starch:

Unripe bananas
Cooked and cooled potatoes and rice
Legumes: beans and lentils
Uncooked rolled oats

How Much Fiber Do You Need?

The recommended daily intake is about 25 grams for women and 38 grams for men. But most people fall short of these numbers, averaging just 15 grams a day. Our Philadelphia nutritionists can help fill this gap!

Pro tip: When bumping up your fiber intake, stay hydrated and take it slow. Fiber absorbs water as it moves through your digestive system, so be sure to drink more water! A good rule of thumb: add 5 grams of fiber to your diet each week until you reach your goal. This looks like:

1 medium apple (about 4 grams)
½ cup cooked lentils (about 5 grams)
1 slice whole grain bread (about 5 grams)
1 cup of broccoli (about 5 grams)
2 tablespoons chia seeds (about 5 grams)

Ways to Add Fiber to Your Diet

Here are some fun, easy, and tasty ways to sneak fiber into your day:

Swap white flour for whole grains or legume-based flours: Try whole wheat, almond, or chickpea flour next time you bake.
Sneak beans into meals: Add them to soups, sauces, tacos, or pasta.
Try fiber-packed pasta: Swap regular pasta for lentil, chickpea, or quinoa-based pasta.
Make a fiber-filled smoothie: Add berries, greens, and seeds (like flax or chia).
Experiment with whole grains: Try millet, farro, or black rice for variety and fiber.
Add fiber-rich veggies to pasta: Try zucchini noodles or spaghetti squash.
Top yogurt with flaxseeds, chia seeds, and berries
Try cauliflower rice: A high-fiber rice alternative for stir-fries or grain bowls.
Snack on fiber-rich options: Try popcorn, roasted chickpeas, or almonds.

Final Thoughts

Fiber is essential for more than just digestion—it supports heart health, nourishes beneficial gut bacteria, and manages blood sugar. It’s one of those key nutrients you definitely don’t want to overlook in your diet.

Whether swapping white bread for whole grain or sneaking some beans into your salad, small changes can make a big difference. If you’re looking for more gut health support, reach out to our team of Philadelphia-based dietitians.

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