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What You Should Know About Fiber (and Where to Get It)

Image of What You Should Know About Fiber (and Where to Get It)
Image of What You Should Know About Fiber (and Where to Get It)

Did you know that your body can’t actually digest fiber? That’s right, the ingredient you’ve heard mentioned in dozens of cereal commercials can’t even be processed by your body.

So what’s the point of eating it in the first place? Well, fiber plays an important role in your digestive system. Let’s dig into its benefits, what foods contain it, and where else you can get more of it.

What is fiber?

Dietary fiber, also called roughage or bulk, is a special type of carbohydrate found in certain plants and other foods. Unlike other carbs, fiber doesn’t get broken down into sugar when you eat it—instead, it passes through your stomach, small intestine, and colon without getting digested.

There are two types of dietary fiber:

  • Soluble fiber: “Soluble” means able to dissolve in water. This type of fiber is known for combating high blood sugar and cholesterol. You can find it in oatmeal, barley, beans, nuts, apples, and berries.
  • Insoluble fiber: This type of fiber doesn’t dissolve, as you might’ve guessed. It’s used as a treatment for constipation. You can find insoluble fiber in whole wheats and grains, brown rice, carrots, tomatoes, and, yes, breakfast cereals.

What are the health benefits of fiber?

For a nutrient you can’t even digest, fiber has a surprising amount of benefits. According to clinical research, a high-fiber diet can reduce your risk of developing coronary heart disease, stroke, hypertension (a.k.a. high cholesterol), and diabetes. That’s because fiber helps make sure your body is efficiently using the sugar you get from other foods.

Fiber’s other big job is to boost the size and weight of your stool. That might sound appealing if you struggle with diarrhea, but we get why you might hesitate if constipation is a more common problem for you. Surprisingly, fiber is a great treatment for constipation too, because bulkier stool is actually easier for your body to pass (the more you know!).

In the long term, keeping your bathroom business running on a regular schedule helps prevent gastrointestinal issues like hemorrhoids, gallstones, kidney stones, and ulcers. It can also help relieve symptoms of acid reflux, gastroesophageal reflux disorder (GERD), and irritable bowel syndrome (IBS).

Wondering how much fiber you should eat every day to get those benefits? Experts say you should aim for 25-30 grams of fiber per day. Keep in mind, though, that quickly ramping up your fiber intake can cause bloating and stomach pain because fiber swells in your stomach after you eat it. Instead, slowly add more fiber to your diet over the course of a few weeks so your digestive system has time to get used to it. And be sure to drink plenty of water—fiber absorbs water to add heft to your stool, so you’ll need to drink an extra glass or two a day to make up for it.

What are the best fiber sources of fiber?

There are two main ways you can get more fiber into your body—through the food you eat, or through supplements.

High-fiber foods

Here are your best choices if you’re looking to add more fiber to your diet:

  • Beans
  • Chickpeas
  • Fruits (Whole fruits, not just juice)
  • Lentils
  • Nuts and seeds
  • Peas
  • Vegetables (Fresh, not canned)
  • Whole-grain bread, cereal, pasta, and rice

Wondering how much fiber is in these foods (or the ones you’re already eating)? This helpful chart lists the fiber content of lots of foods that don’t always come with precise labels, like fresh fruits.

Some foods, like granola bars, have fiber added to them during the manufacturing process. This added fiber is often chicory root, which can actually worsen symptoms of irritable bowel syndrome. (Chicory root is also in the same plant family as ragweed and pollen, so steer clear if you’re allergic to either of those.)

Fiber supplements

While many people can get all the fiber they need from their diets, for some people—especially sufferers of digestive health conditions like IBS—all the fruits and vegetables you can eat never feels like enough. In those cases, it might make sense to consider trying a fiber supplement.

Fiber supplements are available in a variety of forms, including powders, tablets, and even wafers. Regardless of the form, make sure you drink lots of water when you’re taking a fiber supplement. Otherwise, it’s just as likely to cause bloating as a rapid shift to a high-fiber diet would be.

So how can you tell if you need a fiber supplement? “If you suffer from diarrhea or constipation, there’s a good chance you are not getting enough fiber,” says gastroenterologist and digestive health expert Dr. Jason Reich. But for some people, fiber’s not the best way to treat those issues. “Those with gastroparesis, colitis flares, or bowel blockages should avoid fiber because it can worsen symptoms.”


Now that you know just how much fiber can do for your health and the best sources of it, you’re well-prepared to work out a plan to get more fiber into your diet. A good place to start is tracking your current fiber intake, and any digestive symptoms you’re experiencing, to find out where you might be falling short.

Once you know how much fiber you need to aim for to avoid symptoms, you can figure out whether food, supplements, or a mix of both is the best way for you to hit that target.


The information provided in this article is not a substitute for professional medical advice, diagnosis, or treatment. You should not rely upon the content provided in this article for specific medical advice. If you have any questions or concerns, please talk to your doctor.