The body can't digest a type ofCarbohydrate that isDietary fiber. Fiber passes through the gut relatively undamaged, unlike other carbs which are broken down into sugar molecule.

It is important that we get enough fiber from our diet, because it helps to support healthy digestion, weight management, blood sugar regulation and much more. It has been linked to longevity and a decreased risk of cancer.

The indigestible parts of plant-based foods are referred to as dietary fiber. Men aged 50 and under should aim for 38g of fiber per day, while those over 50 should aim for 30g. Women aged 50 and under should get 25g, while those over 50 should get 21g. The average American consumes just 15g of fiber per day.

How can we make sure we get enough fiber from our diet? Everything you need to know about fiber can be found here.


What types of fiber are there?

There are two main types of fiber. Soluble fiber is a type of fiber that becomes a gel-like substance when dissolved in water. While in the body, insoluble fiber mostly retains its shape.

There are benefits to both insoluble andsoluble fibers. Soluble fiber slows down the absorption of sugar into the blood because it mixes with food. The cholesterol is removed from the stool.

The passage of food through the GI tract can be sped up by insoluble fiber. It helps to maintain regularity. It attracts water into your stools, making them easier to pass.

Most plant-based foods contain both insoluble andsoluble fiber, but the amounts of each vary in different foods.

Good sources of fiber include:

  • Beans
  • Lentils
  • Oatmeal
  • Peas
  • Citrus fruits
  • Blueberries
  • Apples
  • Barley

Green Apples

(Image credit: Daxiao Productions |

Good sources of insoluble fiber include:

  • Foods with whole-wheat flour
  • Wheat bran
  • Brown rice
  • Cauliflower
  • Potatoes 
  • Tomatoes
  • Cucumbers 


(Image credit: Tim UR | Shutterstock)

Some foods, like nuts and carrots, are good sources of fiber.

What are the benefits of fiber?

Healthy digestion

"Dietary fiber aids in improving digestion by increasing stool bulk and regularity," said a Utah-based dietitian. This is the best benefit. It's easier to pass a bigger, softer stool than a hard one, which makes life more comfortable and helps to maintain colorectal health.

Increasing your fiber intake can impact your gut health. A two week increase in fiber can change a person's gut microbiome, including an increase in the species that help to break the fiber down, according to research published in mSystems.

Heart health

Kelly Toups is a registered dietitian with the Whole Grains Council. bile acids are made with cholesterol. The amount of bad cholesterol in the blood is reduced by the removal of cholesterol from the blood. A review in the Journal ofChiropractic Medicine found that people who consume higher amounts of fiber have a lower risk of cardiovascular disease.

Blood sugar regulation

The Journal of the American Board of Family Medicine published a meta-analysis of studies that found that increased fiber intake can reduce the amount of blood sugar in the body.

The levels of HbA1c decreased with increased fiber. Glycated hemoglobin is a type of blood sugar stabilizing molecule.

Possible cancer prevention

The link between colorectal cancer prevention and fiber has been mixed. According to the National Cancer Institute, a high-fiber diet does not reduce the risk to a clinically significant degree, but a meta-analysis from the British Journal of Medicine found an association between cereals and colorectal cancer risk.

A recent animal study suggested that fiber might only cause this benefit if a person has the right amount of gutbacteria. Fiber can ferment into a chemical called butyrate, which can cause cancer by making cancer cells self-destruct. A high-fiber diet can help encourage the growth of the butyrate- producing bacteria in some people.


Some scientists think fiber could help people live longer. A meta-analysis of relevant studies published in the American Journal of Epidemiology concluded that high fiber intake may reduce the risk of mortality.

Food allergies and asthma

Scientists have been puzzled by the existence of a role that fiber could play in preventing food allergies. The interaction between fiber andbacteria in the gut is what this theory is about.

Scientists theorize that people aren't producing the right gutbacteria to tackle foods that are associated with allergies. Particles of these foods can enter the bloodstream if the rightbacteria are not present. Clostridia is a bacterium that helps keep the gut secure.

Fiber might help people with asthma. Particles escaping the gut and entering the bloodstream can cause inflammation. A study published in Nature Medicine found that mice on a high-fiber diet were less likely to have asthma.

Should you take a fiber supplement?

People who don't get enough fiber in their diet often turn to supplements. Smathers reported that supplements are not as good as fiber from whole foods, but fiber supplements can be helpful for people who suffer from constipation. If you can get enough of them, they have the same cholesterol-lowering and blood sugar stabilization effects.

If you want to get the same effect as eating peas or lentils, you need a supplement that has more fiber than a yogurt.

If you add supplements to foods that aren't high in other vital vitamins, you won't get them.

Fiber supplements can interact with some drugs. They can cause the same symptoms as the real thing.

  • Related: Should vegans take supplements?

How to eat a high-fiber diet

Many people adopt a high-fiber diet in order to get all the benefits of fiber. Adding 5g of fiber a day for two weeks is recommended by the University of Michigan. If fiber is consumed too fast or in excess, it can cause problems. Your body will get used to having more fiber.

The University of Michigan says to drink with care. Adding too much caffeine to a high-fiber diet can cause snoozing. For every cup of coffee, aim for two cups of non-caffeinated fluids.

The following tips were recommended by Smathers.

  • Add fruit (especially berries) to every meal.
  • Start the day with bran cereal or oatmeal and berries.
  • Add beans or legumes to a lunchtime salad or soup, or have a bean or lentil burger rather than one with meat.
  • At dinner, add high-fiber vegetables like broccoli, corn and turnip greens to meat sauces. Combine with whole-wheat pasta or brown rice. 

A healthy breakfast

(Image credit: Healthy breakfast photo via Shutterstock)

Should you ever follow a low-fiber diet?

A low-fiber diet is sometimes required for medical reasons. According to the University of Pittsburgh Medical Center, those undergoing surgery, radiation or chemotherapy often need a rest. People suffering from diseases such as diverticulitis, inflammatory bowel disease and ulcerative colitis can often maintain a low-fiber diet.

According to the National Institute of Health, people on a low-fiber diet should avoid high-fiber foods that make the stomach work harder. Fruits, vegetables, and refined grains are still okay. Also avoid spicy foods, fried foods, and processed meat.

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