Let me tell you something about fiber. When I first began my study of nutrition about 2 1/2 years ago, my very first nutrition professor was a fiber nerd! She loved fiber and talked to us about it like it was the best thing since sliced (whole grain) bread. Over time, I’ve realized why she was so passionate about this special type of carbohydrate.
It truly is awesome because it plays host to many benefits for our health; they’re vast and highly effective for our body’s proper functioning, so I wanted to take this time to define fiber, talk about why it’s so awesome, and provide some recommendations on how much should be consumed daily.
wtF is Fiber?
Hah. Get it?
Anyway, fiber, as mentioned above and in one of my original posts on my website about carbs, fiber is a type of carbohydrate. But, it’s very special. One reason is because fiber cannot be fully digested. Our bodies do not possess the proper enzymes and digestion systems to fully break it down. Why is it so hard for the body to break down? There’s a few reasons for that.
Fiber, on a very small-scale level is made up of A LOT of sugar molecules. Collectively, these bundles of sugar molecules bonded together are known as polysaccharides. Specifically, fiber is derived from cellulose¹. You may have heard of cellulose as being the cell walls of plant cells. FUN FACT.
Think of a long chain of beads like the picture below.Imagine that each bead represents one molecule of sugar. Now, imagine that this necklace is a chain of at least 1000 beads. That is fiber. Crazy, right? Our body will get fiber from food and there are a few interesting things that happen when we consume fibrous foods.
Function of Fiber
Primarily, our blood sugar begins to level off. When looking at graphs depicting levels of glucose in the blood, we’ll often see a huge spike in blood sugar levels when we eat sugary foods and things containing simple carbohydrates. Keep in mind simple carbs refer to small chains or single units of sugar that the body can quickly break apart and utilize for energy.
With fiber, we don’t see that spike. What we see is a gradual increase in blood sugar and a peak that doesn’t typically get as high as the peak would be from simple carbs. Additionally, blood sugar levels taper down at a slower rate than simple carb spikes. This has a lot of interesting health implications and is the fundamental idea behind diabetes and insulin resistance. I won’t go into how we develop Type 2 Diabetes in this post. I’ll probably talk about Diabeetus another time.
The slow and steady increase and decrease results from the body’s inability to digest fiber. Since we can’t break down fiber completely, it will sit in the gut and become “food” for our gut’s microbiome, a “community” of microorganisms that live inside us. While we don’t have the digestive system to break down fiber, the organisms living in our gut do to some extent. So they will partially break down fibers and convert them into fatty acids that we can break down and use for energy in a process called fermentation. This process takes some time, and we get fatty acids out of it, which take a while to break down in their selves, so this is what leads to that progressive increase and decrease in blood sugar. Pretty cool, right??
This is important for our health because small and slow increases in blood sugar are easier on our pancreas. Our pancreas secretes the hormone insulin that allows sugars to be shuttled into cells for energy. Slower and steadier increases mean less insulin has to be produced and secreted at any given time. Long-term production of insulin for large spikes is a risk factor for diabetes. For this reason, fiber has been noted as a component of the diet that can reduce the risk of Type 2 Diabetes².
Additionally, fiber can help lower your cholesterol and and risk for heart disease². The way this works is that as fiber travels through your digestive system, it will bind to cholesterols that are floating around in the blood, and, since fiber can’t be digested, it will be excreted with some cholesterol still bound to it. The cholesterol that is removed is the LDL or “bad” cholesterol. In effect, this excretion of LDL lowers our blood pressure and risk of heart-related diseases²! I think that’s cool. Maybe just me.
On a side note, fiber also keeps you fuller for a longer period of time than other carbohydrates. When consumed, fiber will slow the rate of digestion for the entire meal, keeping food in your stomach and fighting hunger for a longer period of time. So, if you know that you’re going to be out for awhile, having a meal high in fiber can ensure that you will be full and energized throughout the day!
Sources of Fiber
But where do we get foods high in fiber? Glad you asked. It’s the typical “healthy” foods. I know, booooo; but, fruits, vegetables, legumes (think beans and peas), and whole grains are the most common sources. Ever have some fruit, then get a sense of fullness afterwards? Happens to me with bananas. That’s the fiber bruh!
Fruits/vegetables are the hallmark of any healthy balanced diet, and fiber is one reason why. Most fruits/veggies will have a fair amount of fiber per serving. Simply check the nutrition facts panel to see how much!
Legumes are things like beans, peas, lentils, etc. They’re often packed with fiber AND protein. Double whammy!
When I mention “whole grains”, I’m talking about oatmeal, quinoa, brown rice, and whole grain products (bread, pastas, tortillas, etc.). For the last set of products, make sure the package says “whole grain” or “whole wheat” somewhere or on the ingredients label to ensure you’re getting the most fiber possible.
The American Dietetic Association is very credible source (obviously), and they recommend the following for individuals². You can find the source of this chart on the 2nd reference I have listed:
Of course, you’re not going to die if you don’t hit that fiber number, but it is a good idea to actively aim for around that number listed for your age group. Having a fruit/vegetable at every meal is an easy way to start that. Or just include one more veggie than you’re already having. Small steps is the way to big successes!
Last thing, MORE IS NOT BETTER. Jumping your fiber intake rapidly or getting too much fiber may make you constipated and/or cause a lot of wind-breaking (toots, farting, passing gas, pick your favorite). As you increase your intake, make sure you’re drinking more water too in order for the digestive system to continue moving. Too much fiber can back you up if water isn’t in check. Happy eating!
- Fiber is a type of carbohydrate that can’t be broken down in the body completely
- Fiber has a lot of health benefits including lowering blood pressure and blood sugar²
- Sources of fiber are the typical healthy foods like fruits, veggies, whole grains, and legumes
- An adequate intake of fiber varies with age and sex, refer to the chart to see where you stack up!
Have questions?? Comment below about them or tell me your favorite ways to get fiber in your diet! Thanks of reading!