When people see the label “Rich in fiber” on the cereal box, they always consider this as a “healthy meal” sign. And they are absolutely right! However, most of the people are not aware of what exactly dietary fiber is, and what are its types and benefits.
But here you will learn all about those!
Let’s get going!
What is dietary fiber?
Dietary fiber, also known as simply “fiber,” is a type of compound, which is naturally found in cereals, vegetables, and fruits. It is considered to be a carbohydrate, but before you ban dietary fiber out of your diet, because “carbohydrates can lead to weight gain,” let me emphasize on the fact that fiber is a particular type of carbohydrate, which is not digested, nor absorbed by the body. [1]
While regular carbohydrates turn into sugar molecules (when metabolized), fiber doesn’t break down into such molecules. Instead, it passes through the body without raising the blood sugar levels. In fact, evidence suggest that fiber may support the balance of blood sugar levels, maintain healthy digestive system, and have various additional positive health effects. [2]
Why is fiber healthy?
Before sharing why and how fiber can be beneficial to the health, we shall mention that two types of fiber exist: soluble and insoluble. Usually, all naturally fiber-rich foods contain both soluble and insoluble fiber. However, often certain foods are richer in soluble, and others- in insoluble fiber. [3]
As already mentioned, the regular consumption of dietary fiber can be associated with significant health benefits. But how the different types of fiber can help you to improve your wellbeing?
Why is soluble fiber good for you?
Soluble fiber dissolves in water and other digestion fluids (that’s where the name comes form). As a result, it forms a gel-like material, which fills up the stomach and slows down the digestion process. This way, soluble fiber may brings several important health benefits [4]:
- May prevent sharp fluctuations in blood sugar levels. Therefore, it is highly beneficial for keeping healthy blood sugar levels and preventing diabetes type 2. It can also help people who already suffer from type 2 diabetes to control their condition.
- Can keep you full for a longer period of time. This way, fiber can make you eat less frequently (and smaller quantities of food), lowering your daily calorie intake. This can be associated with improved portion control and weight management, as well as reduced the risk of obesity.
- May reduce the risk of heart disease. The consumption of soluble fiber can be associated with significant decrease in LDL cholesterol and improved total cholesterol profile in the blood. This way, fiber may lower the risk of cardiovascular diseases and hypertension.
- May support good digestive bacteria. When dissolved, the soluble fiber may support the balance of gut microbiota and the reproduction of healthy bacteria and probiotics. This way, fiber may contribute to a healthier digestive system and control intestinal health. Besides, by absorbing the excess water in the intestines, soluble fiber can be effectively used to prevent diarrhea.
Why is insoluble fiber important?
It does not dissolve in water but helps the digestive system to work better by supporting the movement of material (foods, drinks, supplements, etc.). This type of fiber is not linked to weight loss, as it quickly passes through the stomach. However it has other health benefits [5]:
- May support gut health. The insoluble fiber can speed up intestinal movement and have positive effect on relieving (chronic) constipation, and prevention of hemorrhoids and colon folds. In that sense, this type of fiber may worsen the symptoms of diarrhea.
- May reduces the risk of colorectal cancer. Evidence suggests that the consumption of insoluble dietary fiber may play role in prevention of colon and rectal cancer.
Which foods are rich in fiber?
As we already mentioned, almost all fruits, vegetables, cereals and whole grains contain both soluble and insoluble fiber. But as some foods are richer in soluble fiber than insoluble (and vice-versa) will divide the foods into two categories [6][7]:
Foods rich in soluble fiber:
- Oatmeal
- Apples
- Sweet potatoes
- Nuts
- Seeds (flaxseed, chia)
- Beans, lentils
- Berries
- Psyllium husk
Foods rich in insoluble fiber:
- Whole wheat flour (bread, cereals)
- Brown rice
- Barley
- Fruits with edible seeds
- Dark-leaf vegetables
- Carrots
- Beans and lentils
- Celery
- Cucumbers
- Courgettes
Conclusion
Fiber consumption is a natural way to improve your wellbeing. But don’t forget that when you increase fiber intake, you should also increase the consumption of water (because fiber dilutes or bounds with water in the body).
Another key thing is that fiber may not be as beneficial to people suffering from IBS and IBD. If you are diagnosed with IBS, IBD, or experience any related symptoms, it’s important to visit your healthcare provider and follow his/her advise.