Dietary Fiber – All You Need to Know

11 mins read

Fiber is critical to human digestion, but most of us fail to eat enough. Most adults eat less than half the recommended daily intake of fiber.

Perhaps confusion plays a role in this. There are two types of fiber; soluble and insoluble. These fibers are found in different kinds of food, and serve different purposes in the body. However, they’re both equally important.

Soluble fiber, once digested, attracts water from the body. This turns the contents of your stomach into a form of gel, which sits in the stomach. Think that sounds unappealing? Think again.

The paste formed by soluble fiber provides several health benefits, which we’ll discuss shortly.

Insoluble fiber, meanwhile, passes quickly through the digestive tract. It doesn’t pass Go, and it doesn’t collect $200. This is why insoluble fiber keeps our bowel movements regular. As it moves through the body, it thickens up and makes for a healthy, bulky stool.

What types of fiber are there?

Fiber is divided into soluble and insoluble. Most natural plant foods contain both types of fiber, albeit in different proportions. For example, oat bran contains about 50% soluble fiber of the total fiber, while wheat bran – only 20%. Despite the different ratios, both types of fiber are useful and important for human health.

Soluble fiber

They form a gel-like layer around food in the stomach and thus slow down the absorption of glucose, cholesterol, and triglycerides into the blood. Oat bran, legumes (white beans, lentils), unpeeled fruits, and vegetables are rich in soluble fiber.

For example, apple peel contains much more fiber than natural apple juice; unpeeled potatoes are richer in fiber than mashed potatoes.

Insoluble fiber

They are rich in wholemeal flours and raw green plants. They help to quickly empty the colon. In this way, carcinogenic and toxic substances are eliminated from the body faster.

What does fiber do to the body?

Fiber differs from the other major food groups in that it’s never actually digested. (1)

Instead, soluble fiber acts as a barricade that delays the digestion of different foods. This is particularly impactful if your diet is high in sugar.

The fiber prevents sugar from being absorbed into the bloodstream and prevents spikes in blood sugar levels. This is why fiber is particularly important for anybody living with or at risk of contracting diabetes.

What Does Sugar Do to Your Body?

Also, soluble fiber sits in the stomach for a prolonged period. This means that we feel full and satisfied for longer.

Unlike simple carbs, which almost immediately flood our body with sugar and leave us craving more of the same, soluble fiber releases energy slowly and steadily. It also acts as a buffer, preventing undesirable ingredients from seeping into the body.

As discussed, insoluble fiber beats a hasty retreat through the body. In doing so, it flushes your intestines of any unwanted food remnants. If you frequently struggle to digest heavier foods (red meat is a common culprit for this), insoluble fiber will help a great deal.

What are the benefits of fiber intake?

  • reduces appetite as it satiates and dieting is no longer so time-consuming
  • helps with constipation and other colon problems (diverticula, hemorrhoids)
  • lowers the level of “bad” (LDL) cholesterol, as it hinders the full absorption of some fats, and reduces the risk of atherosclerosis
  • binds carcinogens and toxins in food and gets rid of them faster, and this is a protective mechanism against colon cancer
  • slows down the rate of digestion of complex carbohydrates and thus reduces their glycemic index, no sharp changes in the insulin curve are observed
  • slows down the absorption of simple carbohydrates
  • helps with weight control
  • reduces the daily need for insulin production by preventing obesity

What are the benefits of a high-fiber diet?

The most significant benefit of fiber is the boost it provides to your digestive tract. If you eat fiber regularly, you’ll be considerably more regular in your bathroom schedule. Naturally, this means that constipation is not a concern. (2)

Also, you will be significantly less likely to contract a bowel-related illness. Hemorrhoids, for example, are nobody’s friend. Besides, consuming appropriate amounts of the fiber reduces the risk of diverticulitis, aka inflammation of the large intestine. Even bowel cancer can be avoided by eating sufficient fiber.

If that isn’t enough to convince you to switch from white bread to whole grain, consider the impact that fiber has on your heart. More and more people are living with heightened cholesterol, as the demands of 21st Century life take their toll on our diets. This leads to fatty deposits on the heart, which in turn leads to an enhanced risk of stroke or heart disease.

Like fiber, cholesterol is divided into two categories – colloquially known as ‘good’ and ‘bad.’ By consuming soluble fiber, levels of bad cholesterol are drastically reduced. Fiber also dampens the impact of inflammation and heartburn and even lowers blood pressure.

Finally, think about the impact that fiber will have on your waistline. If you consume soluble fiber, you’ll be less hungry. This, in turn, means that you’ll eat less – and won’t gain weight. Fiber is critical to maintaining a healthy weight.

Here are some tricks to increase fiber in your diet:

  • Start with a breakfast of oatmeal and wheat germ
  • Eat wholemeal bread and check the labels of the types they offer in your supermarket
  • When you have the opportunity, use whole flour instead of white
  • Eat wholegrain spaghetti and pasta instead of traditional ones
  • Eat more vegetables during the day
  • When possible, eat vegetables and fruits with their peel
  • Instead of fresh fruit juice, eat the fruit itself
  • Include legumes such as lentils, soy, and others in your daily menu
  • If you are cooking, put more vegetables in the dish (soups, stews, etc.)
  • Buy fiber in the form of a dietary supplement

Important: Do not forget to monitor the total intake of carbohydrates and especially sugars, because foods rich in fiber are rich in other types of carbohydrates!

What foods are high in fiber?

There are a great many foods that are high in fiber. This means that a high-fiber diet doesn’t need to be boring. You can introduce plenty of variety to your meals without sacrificing this crucial nutrient.

Examples of high-fiber foods include:

Fresh fruit

Go easy here, though, as the fruit is also high in sugar.

Green vegetables

As a rule, the darker green the vegetable, the better for your health.

Whole wheat loaves of bread and cereals

Consider switching to rye or pumpernickel bread, and turn from white rice to brown.

Beans and pulses

Kidney beans and lentils are excellent sources of fiber, and they’re also high in protein.

Nuts and seeds

Almonds, seeds, and pistachio needs are great fibrous snacks, especially compared to potato chips. They’re very fatty though, so consume in moderation.

These foods can be consumed alone as snacks, or combined with other ingredients to make complete meals. It doesn’t matter how you consume dietary fiber. What matters is that you do so.

How much fiber should we consume each day?

It is recommended to take 14 grams for every 1000 calories from your intake. People on fat loss diets are advised to eat more fiber because of the above benefits. Do not include the whole amount at once as this can lead to gastrointestinal complaints (flatulence) and even upset glycemic control. Drink enough water so as not to clog the digestive system.

The required dose for children is calculated by adding the number 5 to their age. Example: A 6-year-old child needs 11 grams per day (6 + 5 = 11)

Children, adolescents, and the elderly have less need and tolerance for fiber.

Important: A low-calorie or vegetarian diet rich in insoluble fiber – especially if for a long period of time – can lead to a deficiency of calcium, iron, zinc, vitamin B 12.

With heavy low-carb diets and high fiber intake, insulin is significantly reduced and hypoglycemia should be considered.

When is the best time of day to eat fiber?

Fibers should be consumed in every meal, wherever possible, and realistic. Overdoing it and eating your entire daily allowance in one meal can wreak havoc on your bowels.

However, breakfast is the optimum time to stock up. Fiber releases energy slowly and methodically. A high-fiber breakfast means you’ll be less likely to crave sugary snacks in the afternoon.

Far too many of us fail to consume enough fiber, and that harms our general health. Check the recommended daily intake guidelines and adjust your diet accordingly. You’ll be glad that you did so.

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