The ‘F’ Word – Fiber

Eat more fiber. You’ve probably heard it before. But do you know why fiber is so good for your health?


Dietary fiber — found mainly in fruits, vegetables, whole grains and legumes — is probably best known for its ability to prevent or relieve constipation. But foods containing fiber can provide other health benefits as well, such as helping to maintain a healthy weight and lowering your risk of diabetes, heart disease and some types of cancer.

What is dietary fiber?

First, let’s talk about what exactly fiber is.  Also known as roughage or bulk, fiber includes undigestible parts of plant foods. Unlike other food components, such as fats, proteins or carbohydrates — which your body breaks down and absorbs — fiber isn’t digested by your body. Instead, it passes through your entire digestive tract, with little breakdown and then you excrete it out of your body.

There are two types of fiber – soluble, which dissolves in water, and insoluble, which doesn’t dissolve.

  • Soluble fiber.This type of fiber dissolves in water to form a gel-like material. I always remember it as a sponge. It helps to absorb things like when you use a sponge to absorb liquid.
    • Soluble fiber can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium.
  • Insoluble fiber.This type of fiber promotes the movement of material through your digestive system and increases stool bulk, much like a scrub brush. What that means to you is – it helps to fight constipation or irregular stools and keep you regular!
    • Foods higher in insoluble fiber include nuts, beans and vegetables, such as cauliflower, green beans and dark leafy greens like kale and spinach.

The amount of soluble and insoluble fiber varies in different plant foods, so it’s best to, eat a wide variety of high-fiber foods.

6 Ways a High-Fiber Diet Benefits You

  1. Regular bowel movements.Dietary fiber increases the weight and size of your stool and softens it. A bulky stool is easier to pass, decreasing your chance of constipation. If you have loose, watery stools, fiber may help to solidify the stool because it absorbs water and adds bulk to stool.
  2. Helps maintain bowel health.A high-fiber diet may lower your risk of developing hemorrhoids and small pouches in your colon (diverticular disease). Studies have also found that a high-fiber diet likely decreases the risk of colorectal cancer.
  3. Lowers cholesterol levels.Soluble fiber found in beans, oats, flaxseed and oat bran may help lower total blood cholesterol levels by lowering low-density lipoprotein, or “bad,” cholesterol levels.
    • Studies also have shown that high-fiber foods may have other heart-health benefits, such as reducing blood pressure and inflammation.
  • Helps control blood sugar levels.Fiber, particularly soluble fiber — can slow the absorption of sugar and help improve blood sugar levels. When you eat foods high in fiber, such as beans and whole grains, the sugar in those foods is absorbed slower, which keeps your blood glucose levels from rising too fast.
    • Additionally, adding higher fiber foods with simple carbs or sugary foods – can also help slow the overall absorption of sugar, keeping blood glucose levels from quick spikes.
    • A healthy diet that includes insoluble fiber may also reduce the risk of developing type 2 diabetes.
  • Aids in achieving healthy weight.High-fiber foods tend to be more filling than low-fiber foods, so you’re likely to eat less and stay satisfied longer. And high-fiber foods tend to take longer to eat and to be less “energy dense,” which means they have fewer calories for the same volume of food.
  • Helps you feel satisfied longer.Fiber takes longer to digest than simple carbs and processed sugar. Adding more fiber to your meals and snacks helps you feel satisfied and that can in turn decrease cravings.

Tips to Increase Your Fiber Intake

Increasing the amount of fiber in your diet can lead to uncomfortable digestive symptoms such as bloating, gas, constipation, diarrhea, or cramps.

Take it slow: Increase the fiber in your diet gradually, adding a bit more every few days. Spread your fiber intake throughout the day rather than cramming a lot of fiber into single meals or snacks, and drink plenty of water. Some simple ways to start:

  • Aim to eat 3 to 5 servings of non-starchy vegetables each day (a serving is 1/2 cup cooked or 1 cup raw)
  • Consume two servings of high-fiber fruits such as berries, apples, or pears daily (a serving is 1/2 cup berries or 1 small piece of fruit, or 1/3 of a large banana)
  • Include plenty of whole grains, such as whole-grain bread, oatmeal, and ancient (quinoa, bulgar, barley, farro, millet, freekeh)
  • Snack on unsalted nuts—one serving is 1/4 cup or one handful
  • Sprinkle ground flax, hemp, or chia seeds into your yogurt, oatmeal, or cottage cheese
  • Toss legumes, such as chickpeas, into your salad for a protein and fiber boost

When reading labels, note that any food containing 5 grams of fiber is considered an “excellent” source, according to the American Diabetes Association, and foods with 2.5 grams to 4.9 grams are “good” sources.


  1. Mayo Clinic.Dietary fiber: Essential for a healthy diet. November 16, 2018.
  2. Weickert MO, Pfeiffer AFH. Impact of dietary fiber consumption on insulin resistance and the prevention of type 2 diabetesJ Nutr. 2018;148(1):7-12. doi:10.1093/jn/nxx008.
  3. Quagliani D, Felt-Gunderson P. Closing america’s fiber intake gapAm J Lifestyle Med. 2017 Jan-Feb; 11(1): 80–85. doi:10.1177/1559827615588079.