Dietary Fiber 101: Why Do We Need It?

Dietary Fiber 101: Why Do We Need It?

Fiber, it’s something we all need in our diets, as it supports several different body systems. Plus, fiber is associated with greater digestive health as well as a reduced risk for several major diseases, including type 2 diabetes, cardiovascular disease, stroke, hypertension, certain gastrointestinal disorders, obesity, and even certain types of cancer.

A significant portion of the population fails to get in enough roughage each day. Recent estimates indicate that as much as 95% of the population fails to consume enough dietary fiber each day. <1>

To help everyday men and women hit their fiber quota, food manufacturers have begun adding "functional fibers" to their packaged and processed goods.

Everything from protein bars to meal replacement powders and even peanut butter has seen the addition of these extra fibers.

But, not all functional fibers are created equal.

Some aren't fibers at all (we’re looking at you isomalto-oligosaccharides ). <7,8>

Today, we take a deep dive into all things fiber as well as look into one of the newest functional fibers you may find in your next packaged food or dietary supplements.

So, let’s start at the top!

What is Fiber?

Dietary fiber is a type of carbohydrate found in plants that is indigestible by the human body, which means our bodies do not break it down and derive little to no energy from it like it would with other dietary carbohydrates, such as sugar or starch. A typical example of dietary fiber is cellulose.

Types of Dietary Fiber

There are two main types of dietary fiber that you will find in plants:

  • Soluble
  • Insoluble

As the name suggests, soluble fiber dissolves into water, and insoluble fiber does not.

When soluble fiber dissolves into water, it forms a thick, viscous gel that enhances digestion, binds up cholesterol, and helps to reduce its level in the blood. Soluble fibers have also been noted to help reduce blood sugar spikes as well as offer other metabolic health benefits. <2> Foods high in soluble fiber include beans, oats, lentils, and barley as well as certain fruits and vegetables, including apples or carrots.

Since insoluble fibers do not dissolve in water, they remain mostly intact during their journey through the digestive tract, and they serve mainly as a "bulking" agent in stool and may help encourage the passage of food and waste through the GI system. <3> Insoluble fiber is mostly found in the outer bran layer of grains (for example, wheat bran) and vegetables.

Now, there is a special subset of fiber called fermentable fiber.

Fermentable fiber is a type of soluble fiber that serves as food for the friendly ("good") gut bacteria. As the bacteria ferment (digest) the fiber, they also produce compounds called short-chain fatty acids (such as butyrate) which provide the primary energy source for the cells lining your colon and serve an important role in colon health . <4,5>

Note, you may have also heard fermentable fibers referred to as prebiotic fibers. Essentially, prebiotic fibers are the food that feeds the bacteria in your gut to keep them healthy and strong. Two of the best sources of naturally occurring dietary fiber are beans and legumes. Be aware that one of the by-products of the fermentation process carried out by your gut bacteria is gas.

Therefore, if you consume a high amount of fermentable fiber in a rather brief period, you may be in store for some mild GI discomfort and flatulence...all the more so if you're not used to eating a decent amount of fiber each day.

Note that prebiotics are different than probiotics.

Probiotics are live bacteria cultures naturally occurring or added to fermented foods (yogurt, kimchi, sauerkraut, etc.) and dietary supplements that may increase the density and diversity of good gut bacteria. They are beneficial to the digestive system and immune support function. <6>

Up to this point, the fiber we have been discussing is dietary fiber, meaning the kind that is naturally present in whole foods. The type of fiber you will find added to packaged and processed foods is referred to as functional fiber.

Functional fibers are nondigestible carbohydrates isolated and extracted from starches or sugars and added to processed food. They may offer some of the same benefits as naturally occurring dietary fiber, such as improving blood glucose regulation and helping to prevent constipation.

Since such a significant portion of the population fails to meet the recommended intake of dietary fiber each day, the use of functional fibers has become increasingly common as a means to help consumers increase their fiber intake and derive similar health benefits associated with naturally occurring dietary fiber sources.

Common examples of functional fibers include:

  • Soluble Corn Fiber
  • Polydextrose
  • Inulin
  • Guar Gum
  • Beta-Glucans
  • Oligofructose

One of the more recent functional fiber supplements to enter the marketplace is a derivative of guar gum called Sunfiber®. We'll dig into Sunfiber® a bit later on, but first, let's answer another question that's likely on your mind...

How Much Fiber Do I Need?

The recommended daily intake of fiber for men is 31-38 grams of fiber (depending on age), and for women, it’s around 25 grams. <1>

Of course, this is assuming you’re following the average daily calorie intake (~2500 calories for men and ~2000 calories for women).

If your active lifestyle requires that you consume significantly more calories per day than the average, you need to increase your fiber intake accordingly. Current recommendations are to consume 14 grams of fiber for every 1000 calories eaten. <1>

Now, if you currently aren't hitting the recommended intake of dietary fiber, that's ok...but you do need to start working towards that goal. However, if you're currently consuming far less dietary fiber than recommended, it is advised that you slowly start working towards your goal.

For example, if you are a male, who is supposed to be consuming around 30 grams of fiber per day, but is only getting 10 grams per day, do not automatically jump to consuming 30 grams of fiber.

Doing so can lead to quite a bit of bloating, flatulence, and other unwanted GI effects. Let your body slowly adapt to the increased fiber intake by adding an extra 5 grams of dietary fiber to your diet every 3-4 days until you hit your daily intake goal.

Finally, though we tend to think collectively as a society that "if a little of something is good, more of it should be a whole lot better," that's not exactly the case with fiber.

If your daily fiber intake gets too high, you can experience significant bloating, gassiness, and other GI-related issues. You may also reduce your body's ability to effectively absorb nutrients as the fiber is causing them to pass through the GI system too quickly before they can be absorbed appropriately.

Furthermore, excess fiber consumption may also lead to dehydration since water is absorbed in the formation of gel and then eliminated from the body, leaving you with less water left over for other necessary functions.

The bottom line here is that you need to consume enough fiber every day, but there's no need to overdo it.

Sunfiber® -- A Better Functional Fiber Alternative

Sunfiber is an all-natural prebiotic fiber (galactomannan) derived from partially hydrolyzed guar gum. It is transparent, tasteless, and odorless.

According to Taiyo International (the creators of Sunfiber®), It mixes easily into any food or beverage without changing the color, texture, or "mouthfeel." Furthermore, Sunfiber® is stable and soluble at various pH levels and resistant to heat, salt, acid, high pressure, and digestive enzymes. <21>

Sunfiber® is backed by multiple clinical studies denoting guar gum’s ability to help:

  • Increase satiety (both short-term and long-term)<9,12>
  • Reduce between-meal snacking<9>
  • The lower glycemic index of a meal<14,15,16>
  • Improve mineral absorption<17>
  • Maintain digestive health<15>
  • Improves gastric transit time<18>
  • Promote intestinal regularity<11>

Additionally, unlike many other “functional” fibers (as well as some dietary fibers), Sunfiber® alleviates constipation without overly degrading stool firmness or any of the other undesirable and problematic side effects of fiber. <10,11>

As a soluble, fermentable fiber, Sunfiber® has a slow fermentation rate and helps stimulate the release of hormones associated with satiety, resulting in reduced hunger cravings (which is important for those trying to adhere to a reduced-calorie diet!).

How is Sunfiber® Made?

The guar plant, Cyamopsis tetragonolobus L., has been grown in Pakistan and India for centuries where it was used to feed both humans and animals.

In the 1950s, manufacturers were able to process the seeds of the guar plant into guar gum to meet the increasing demand for the product by the food industry.

The problem was that the high viscosity of guar gum limited its applications in various foods and beverages.

Enter partially hydrolyzed guar gum (a.k.a. Sunfiber®).

Sunfiber® is produced via controlled partial enzymatic hydrolysis of guar gum seeds. This “partial hydrolysis” can be thought of as a sort of pre-digestion, mimicking what would happen in the human gut should a person consume some guar seeds.

This pre-digestion process creates a fiber that has a very low viscosity (10x lower than guar seeds, actually).

Whereas adding regular guar seeds to a liquid would lead to the formation of a viscous gel, Sunfiber® (partially hydrolyzed guar gum) can be mixed into liquids and retain the properties of an easily pourable liquid <21>, but with the added benefit of a higher fiber content!

How Much Sunfiber®?

Studies using guar gum fiber (like the kind used to make Sunfiber®) observed improvements in post-meal satiety and reductions in-between meal snacking with as little as 2g of guar gum fiber per feeding. <9>

Is Sunfiber® Safe?


Sunfiber® is extremely well tolerated by participants in human trials and has even been used in the treatment of children and infants with no documented adverse side effects. <19,20>

Furthermore, Sunfiber® also qualifies as a dietary fiber under the FDA’s revamped guidelines for what qualifies as a fiber.

For an ingredient to be classified as a fiber, it must have clinical evidence backing any functional claims. According to these new regulations issued by the FDA regarding dietary fibers, a “fiber” must demonstrate it has a “physiological effect that is beneficial to human health.”

Sunfiber® has multiple studies documenting its "physiological effects" that offer benefits to humans, as we've outlined above. Plus, it comes without the unwanted GI distress of other popular functional fibers on the market, making it an excellent source of fiber to include in dietary supplements.

The Bottom Line on Fiber

Fiber (both soluble and insoluble) are important for a healthy diet, yet many individuals don't get enough fiber in their daily diet. This is a shame as a higher fiber intake has been associated with improvements in several chronic diseases, including type 2 diabetes and cardiovascular disease.

In an effort to improve the fiber content of processed goods, manufacturers have begun incorporating "functional fibers," which are isolated fibers derived from whole foods. Sunfiber® is one of the more noteworthy functional fibers that's been documented to confer several benefits and is known to be well tolerated.

If you’re currently not getting enough daily dietary fiber, takes steps to gradually increase your intake of fiber from a mix of dietary fibers both in whole foods and functional fibers such as Sunfiber®.


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