The Importance of Dietary Fiber

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What Are Dietary Fibers?

Dietary fibers, also known as roughage, are composed of all parts of plant foods that your body cannot digest or absorb.

Nutrients such as fats, proteins, and carbohydrates are absorbed by your body in the small intestine. Dietary fibers are carbohydrates that are not digested by your body in this way. This is because we do not have the enzymes to break them down. As a result, dietary fibers pass fairly intact through your stomach, small intestine, large intestine, and out of your body. It may seem like dietary fibers don’t do much, but they have several important roles in maintaining your health.

Uptake of Water-Soluble Dietary Fibers

Fibers are usually divided into two categories: those dietary fibers that do not dissolve in water (insoluble fibers) and dietary fibers that do dissolve in water (soluble fibers). The soluble or fermentable fibers mix in the stomach with water and other food present. Due to the gel-like structure of the soluble fibers, they stick to substances such as sugars, fats, and cholesterol in the small intestine. This slows down their absorption.

As a result, you feel fuller, reducing your food intake. Another important consequence is that sugars are less likely to cause high blood sugar levels quickly. This reduces the risk of conditions such as diabetes and obesity. This can also affect your total cholesterol and LDL cholesterol levels.

Soluble dietary fibers are found in abundance in oats, peas, beans, apples, citrus fruits, carrots, barley, and psyllium.

The amount of both types of dietary fibers varies from plant to plant. Your health benefits the most from eating a wide variety of foods rich in dietary fibers.

Soluble Dietary Fibers and Cholesterol

In a 1999 study, 67 previous studies on the relationship between fibers and cholesterol were compared. Daily intake of 2 to 10 grams was found to lower total and LDL cholesterol by 4 to 18 percent.

Soluble fibers in the intestines reduce the amount of bile released by the liver. At the same time, they increase the amount of bile passed in the stool. Bile is needed for the digestion and absorption of fats. To compensate for the shortage of bile, the liver produces more bile acids. For this, cholesterol is needed, so the liver then removes LDL cholesterol from the blood. This lowers LDL cholesterol.

Insoluble Dietary Fibers

Some of the insoluble dietary fibers are broken down by bacteria in the large intestine. This provides a modest contribution to energy through the process of fermentation. The non-soluble fibers also help transport materials through your digestive tract. They also increase the volume of feces. Therefore, they help with constipation or irregular bowel movements.

Good sources of insoluble fibers include whole wheat flour, wheat bran, nuts, and many types of vegetables.

Benefits of a Fiber-Rich Diet

A diet rich in fiber-rich foods has many benefits, including:

Healthier Bowel Movements

Dietary fibers increase the weight and size of feces – your poop – and also make it softer. It is easier to expel a larger quantity of feces. If you suffer from loose, watery stools, dietary fibers help make them firmer. They absorb water, adding more bulk to the stool. For some people, dietary fibers also help alleviate the effects of irritable bowel syndrome.

Helps Maintain Healthy Gut Flora

A fiber-rich diet can reduce the risk of hemorrhoids and diverticulitis (infected diverticula in the large intestine). Some dietary fibers ferment in the large intestine, and scientists are investigating how this can play a role in preventing diseases of the large intestine.

Reduces Your Cholesterol Levels

Soluble fibers – found in beans, oats, flaxseed, and oat bran, among others – probably help lower your total cholesterol level in your blood by reducing the level of low-density lipoprotein – LDL or ‘bad’ – cholesterol.

Epidemiological studies have shown that a higher fiber intake in your diet can lower blood pressure and the risk of infections, which is also good for heart health.

Helps Control Your Blood Sugar Levels

Fibers, especially soluble dietary fibers, can slow down sugar absorption, which can help people with diabetes improve their blood sugar levels. A dietary pattern containing soluble fibers has been shown to reduce the risk of type 2 diabetes.

Fibers Improve Insulin Sensitivity

Research on diabetes has shown that fat cells and muscle cells become more sensitive to insulin. For fat cells, this means they are better able to absorb sugar from the bloodstream. For muscle cells, this means they use more amino acids to make proteins in the muscles. In this way, dietary fibers can contribute to muscle growth, although such a relationship has not yet been demonstrated in research.

Helps with Weight Loss

High-fiber foods usually require more chewing time, giving your body time to tell you that you’re no longer hungry. This reduces the likelihood of overeating. In addition, high-fiber foods make the meal larger and keep it in your stomach longer, making you feel fuller longer. A high-fiber diet also usually provides less energy, which means fewer calories in the same amount of food.

There are still unclear indications that fibers have an effect on colon cancer. Some studies show improvements, others show nothing, and still others show deteriorations.

How Much Fiber Do You Need?

How much fiber do you actually need daily? The American National Academy of Sciences’ Institute of Medicine, which advises on health matters on a scientific basis, recommends the following daily amounts for adults:

The Best High-Fiber Food Choices

If you don’t get enough dietary fiber daily, it’s advisable to eat more of it. Some good choices include:

• Grains and whole grain products
• Fruits
• Vegetables
• Beans, peas, and other legumes
• Nuts and seeds

Purified or processed foods – such as canned fruit and

pulp-free fruit juice, white bread and pasta, and cereals without whole grain – contain very little fiber. Purifying grain removes the outer layer of the grain, reducing the amount of fiber. This rule also applies to removing the peel from fruits and vegetables.

Fresh organic food is generally better than fiber supplements. Fiber supplements – such as Metamucil, Citrucel, and Fibercon – do not contain the vitamins, minerals, and other beneficial nutrients found in fiber-rich foods.

For some people, however, a fiber supplement can be a solution when dietary adjustments do not produce sufficient results. Or when they have certain medical conditions such as constipation, diarrhea, or irritable bowel syndrome. Consult your doctor to see if using a fiber supplement is a good choice.

Tips for Getting More Fiber

Need ideas for high-fiber meals and snacks? Try these suggestions:

• Choose high-fiber cereals (five or more grams per serving). Look for cereals with ‘bran’, ‘fiber’, or ‘high-fiber’ in the name. Alternatively, add a few tablespoons of unprocessed wheat flakes to your favorite cereals.
• Switch to whole grains. Look for bread that lists whole wheat flour, whole grain flour, or other whole grain ingredients as the first on the label. Look for a brand that contains at least two grams of dietary fiber per serving. Experiment with using brown rice, wild rice, barley, whole wheat pasta, and bulgur.
• Give your baked goods more substance. Replace half or all of the white flour with whole wheat flour when baking. Whole wheat flour is heavier than white flour. In yeast bread, you can use a little more yeast or let the dough rise longer. If you use baking powder, use one teaspoon for every 300 grams.
• Add pre-cut fresh or frozen vegetables to soups and sauces. For example, add chopped frozen broccoli to spaghetti sauce or add some fresh baby carrots to the stew.
• Incorporate legumes into your meals more often. Eat more beans, peas, and lentils. Put kidney beans in canned soup or in a salad.
• Eat fruit with every meal. Apples, oranges, pears, and berries are good sources of fiber.
• Make snacks count. Fresh and dried fruit, raw vegetables, low-fat popcorn, and whole grain crackers are good choices. Occasionally, a handful of nuts is also a healthy, high-fiber snack.

Finally

Fiber-rich foods are good for your health. When you add too much dietary fiber to your diet too quickly, you risk gas buildup in your intestines, bloating, and cramping. Gradually add the dietary fiber to your diet over a few weeks. This allows the natural bacteria in your digestive system to adapt to the change.

Also, drink plenty of water. Dietary fibers work best when they absorb water, making your stools soft and larger.