Dietary fiber: their health benefits

[Article updated on 19/09/2023]

You probably know the now famous recommendation of “5 fruits and vegetables a day” but do you know why?

Before reading on

I’m not an expert in this field, but I am passionate about nutrition and health.

The articles you’ll find on my site are the result of in-depth research that I’d like to share with you. However, I would like to stress that I am not a health professional and that my advice should in no way replace that of a qualified physician. I’m here to guide you, but it’s important that you consult a professional for specific questions or medical concerns. Your well-being is important. So be sure to consult the appropriate experts and take the best possible care of yourself.

Well, in part, because fruits and vegetables provide our main intake of fiber, essential nutrients for a good nutritional balance. But what are they for?

Focus on these nutrients whose role is often unknown and neglected.

What is this ?

These are carbohydrates contained in plants which are undigested in the small intestine and which have at least one of the following properties:

  • Increased stool production
  • Stimulation of colonic fermentation
  • Decrease in fasting blood cholesterol levels
  • Decrease in blood sugar and/or insulin levels after meals

Fibers exist in 2 forms:

  • Soluble fiber : as their name suggests, they have the property of being soluble in water. So, when they come into contact with water, they become viscous and make it easier for residue to slide. They then slow down the absorption of nutrients such as fats and carbohydrates.

Being gentle on the intestines, they can reduce the risk of diarrhea.

But remember! To be able to act, these fibers need water so make sure you have good hydration! At least 1L5/day, spread over the entire day!

Where to find them? In fruits such as apples, pears, citrus fruits, strawberries… and vegetables such as carrots, green beans… and also in legumes, oat bran, psyllium, flax seeds and chia.

  • Insoluble fiber : they absorb water and increase the volume of stools. They thus make it possible to stimulate intestinal contractions.

In addition, certain studies tend to show that they could reduce the risk of developing digestive and colorectal cancers by increasing the elimination of carcinogenic substances.

Where to find them? In the skin of fruits and vegetables and oilseed fruits (almonds, walnuts, hazelnuts, etc.), whole and semi-complete cereals, flax seeds, dried fruits such as prunes, figs, dates, legumes, etc.


What are our needs?

The recommended fiber intake is 25 to 30 g/day from the age of 10. They decrease to 20 to 25 g/day over the age of 70.

Although these recommendations do not differentiate between soluble and insoluble fiber, it is recommended to consume these 2 types of fiber at the same time. We can also sometimes find them in the same food as is, for example, the case for apples or oilseed fruits.

How to achieve these contributions?

  • By regularly consuming fruits and vegetables using the benchmark of 5 fruits and vegetables/day the size of your fist. They can be eaten raw or cooked, fresh, frozen or canned.
  • By favoring whole and semi-complete cereals such as whole-grain rice, whole-wheat pasta, whole-wheat bread, etc.
  • By integrating oilseed fruits into your diet such as almonds, walnuts, hazelnuts, etc. and preserving the skin. It is recommended to take a handful/day.
  • By consuming legumes (lentils, red beans, chickpeas, etc.). They are recommended at least twice a week.

Essential elements for regular transit

Whether soluble or insoluble fiber, both are necessary for the proper balance of our transit:

  • By filling up with water, soluble fiber will give a viscous texture to our stools and allow them to be more consistent. If you suffer from diarrhea, these fibers should be preferred. For example, by consuming foods like apples, carrots, potatoes… Psyllium is also rich in soluble fiber and has this capacity.
  • Insoluble fiber increases the volume of our stools, their water content and their plasticity. They help fight against constipation. They are mainly found in whole grains, oat or wheat bran, flax seeds, etc. However, for good effectiveness, these fibers need a sufficient supply of water.

Allies for our cardiovascular health

According to several studies, the higher the fiber consumption, the greater the benefit in terms of cardiovascular or coronary risk.

Indeed, fibers not being digested by the intestines, they limit the absorption of fats and thus reduce the level of blood cholesterol, in particular LDL-cholesterol, commonly called “bad cholesterol” because it increases the risk of develop cardiovascular diseases when we have excess.

A good blood sugar regulator

Likewise, fiber helps limit the intestinal absorption of carbohydrates, particularly simple carbohydrates. Thus, blood sugar levels rise less significantly after a meal rich in fiber and this helps avoid blood sugar peaks. These peaks, when significant and repeated, expose you to an increased risk of diabetes.

It is for this reason in particular that, if you wish to eat a sweet food such as a pastry, an ice cream or a dessert, it is better to take it during your meal (as a dessert, for example) rather than alone, as a mid-afternoon. In fact, thanks to the fiber intake in your meal, you will slow down the speed of absorption of these sugars. It is therefore important that each of your meals contains fruits and vegetables. This effect will be slowed even more if you consume whole or semi-complete cereals (whole grain bread, whole grain rice, whole grain pasta, etc.)

An anti-cravings ally

Soluble fibers, when filled with water, slow down digestion. They therefore promote our satiety, that is to say a state of “non-hunger”.

Food for our intestinal flora

Our intestinal flora or microbiota is made up of billions of bacteria essential to the balance of our body. It is this which allows the degradation and fermentation of fibers in our colon to allow their proper digestion.

In addition, like any living organism, these bacteria need to feed. Being undigested by the small intestine, dietary fiber will act as a prebiotic for our microbiota. That is to say, they promote the growth of bacteria which will then be able to carry out their beneficial functions on our health more effectively.

But be careful, if they are provided in excess, the fibers risk causing over-fermentation which will be felt in the form of bloating, abdominal pain, etc.

To conclude, fiber has many benefits that make it essential for maintaining a balanced diet. So remember to include them on your plates!