Dietary fiber performs very important physiological functions in our body. So, although it is not considered a “nutrient”, it is essential to include it in our daily diet. In this post we are going to do a good review of what foods are rich in fiber.
What is fiber?
To begin with, the concept of dietary fiber must be clarified. It is an edible part of plants that resists digestion and absorption in the human small intestine and undergoes partial or total fermentation in the large intestine.
From a nutritional point of view, dietary fiber is not a nutrient, since it does not participate in basic metabolic processes of the body. However, it performs several very important physiological functions.
Dietary fiber is part of the structure of plants, so it is only found in plant foods such as vegetables, fruits, legumes and cereals. It is considered a complex carbohydrate and is divided into two types: insoluble fiber and soluble fiber.
- The insoluble fiber is formed by substances which retain little water and slightly swell. It can be found in foods such as wheat bran, whole grains, some vegetables, and almost all cereals. Its main effects on the body are: cleaning the walls of the intestine and increasing the volume of stool, reducing its consistency and its transit time. That is, it facilitates bowel movements and prevents constipation.
- The soluble fiber is made up of components that capture much water and are able to form viscous gels. It produces a large amount of gas in the intestine and coincides with the effect of the insoluble in that it increases the volume of the stool and decreases its consistency. In addition, it slows down and decreases the absorption of fat and sugars from food, thus helping to regulate cholesterol and glucose in the blood. This type of fiber is found in legumes, in cereals such as oats and barley and in some fruits.
The ideal is to ingest both types of fiber in a 3 to 1 ratio, respectively, and in an approximate amount of 30-35 grams daily. It is also advisable to vary the sources of fiber and combine it with an adequate intake of water.
Benefits of consuming foods rich in fiber
The inclusion of foods rich in dietary fiber in the diet can become certain advantages when it comes to preventing or alleviating different diseases such as:
Constipation:
Dietary fiber increases the volume of stool by creating solid waste and absorbing water, which produces a more voluminous and less consistent stool and accelerates its evacuation.
Diverticular disease:
It is characterized by the appearance of small bags in the walls of the colon in the shape of a glove finger called diverticula. It is a disease that increases with age since older people experience weakening of the intestinal wall and the pressure exerted within the colon facilitates the creation of these diverticula.
Obesity:
Diets rich in fiber can help control this disease since they have fewer calories in the same volume of food and have the ability to slow down the absorption of sugars and fats ingested in other foods. In addition, they facilitate the ingestion of less quantity of other foods thanks to their feeling of satiety.
Colon and rectal cancer:
In isolation, dietary fiber does not protect against these diseases. However, the first epidemiological studies indicated that people with diets rich in fiber had a lower incidence of colon cancer. Although these studies are somewhat contradictory due to the diversity of components that make up dietary fiber, it is accepted that the beneficial effect is in the general diet. A consumption of vegetables, a reduced intake of fat and red meat and an adequate supply of micronutrients.
Diabetes mellitus:
A diet rich in fiber helps improve glycemic control thanks to its ability to decrease hyperinsulinemia and plasma lipid concentrations in type 2 diabetics.
Hypercholesterolemia:
The intake of fiber provides a lower absorption of fat and, therefore, cholesterol. Therefore it prevents and favors the treatment of diseases caused by high levels of cholesterol in the blood.
Contraindications of fiber intake
The fermentation of fiber by anaerobic bacteria in the colon has the possibility of producing flatulence, bloating and pain in this area. Therefore, it is recommended to adjust the fiber intake to the recommended daily amount and carry it out gradually, so that the gastrointestinal tract can adapt.
Higher fiber foods
Legumes:
Legumes are the richest source of minerals, plant-based proteins and, above all, fiber. The white beans natural are the winners because they provide about 7.7 grams of fiber per 100. The lentils are followed closely with about 7.4 grams per 100. And the green beans, for example, contain 3.2 grams of fiber per 100 of product.
Nuts:
Nuts are another of the best sources of fiber. They have a bad reputation for their high caloric level, but they have many benefits if we consume them in moderation. They are satiating, so they help the weight loss process. About 100 grams of almonds provide about 12.5 grams of fiber. If they are nuts, they will contribute 6.7 grams, and peanuts, 8.4 grams per 100.
Apple:
Apples and fruit in general have many beneficial nutrients for the body. An apple has, for example, 5.4 grams of fiber. One peach, 3.4 grams. A banana, 3.5 grams. And a pear of water, up to 7.1 grams. Of course, it is recommended to consume the whole piece of fruit to be able to assimilate all this amount of fiber, since in the form of juice or smoothie its contribution is greatly reduced and the absorption of sugar in our body increases.
Citrus fruits:
In addition to being an excellent source of vitamins and sugars (beneficial when eating the whole piece), we find a good amount of fiber in them. A large orange has 4.4 grams, a grapefruit provides 3.7 grams and a tangerine, 2.2 grams.
Blueberries:
They are fruits of the forest famous for their antioxidant and cardioprotective effects. In addition, they provide 2.4 grams of fiber for every 100 grams of blueberries. They are also delicious!
Tomato:
Tomato is a fruit that provides 1.1 grams of insoluble fiber, such as cereals, for every 100 grams of product.
Carrot:
It is a source of soluble fiber and provides 2.8 grams per 100 grams.
Broccoli:
In addition to being rich in calcium, broccoli provides 2.6 grams of fiber per 100 of product.
Oats:
Oatmeal flakes are ideal to replace cereals at breakfast and they manage to provide around 8.4 grams of fiber for every 100 grams of product.
Green leafy vegetables:
In which we include iceberg lettuce, which provides 1.2 grams of fiber per 100; Swiss chard, which will provide 1.6 grams; or spinach, which have 2.2 grams for the same amount.
Avocado:
This fruit with a reputation for providing healthy fats, also has both soluble and insoluble fibers. In one piece we can find up to 20.4 grams of fiber, almost the recommended daily fiber figure!
Whole grains:
Referring to brown rice, whole wheat pasta and even whole wheat bread, but not the typical breakfast cereals which, in general and with specific exceptions, have a lot of sugar.
