Should I Care About My Fiber Intake?
Updated: Jul 2
Alright if you have been anywhere near the diet industry in the past few years, you probably would have seen the craze of the Carnivore diet light a storm through the internet.
If not, here’s a quick download on what you missed (or didn’t miss really).
It’s essentially a diet where only animal-products are consumed, think meat, organs, butter, eggs… and no plant-products, so no grains, no vegetables, and no fruits.
Even as a meat lover, I still personally find this pretty disgusting.
Imagine steak and eggs on the menu twice a day, seven days a week… *gasps*.
My preferences aside, one big reason this diet is problematic is because it leaves out fiber from the equation completely.
Imagine again, 1 week into your Carnivore diet, and sitting on your toilet bowl every morning, feeling like you are shitting rocks. Don't say I didn't warn you.
And.... because that is how things are nowadays - one particular food group is demonized completely, usually by people who spout incomplete information and a lack of context, I feel the need to jump in and defend it with science and sense!
So that’s exactly what we are going to do in this article on Dietary fiber.
We are going to look at what it is, why we need it, how much to eat, the whole works, let’s dig in!
What is Dietary Fiber?
Dietary fiber is a plant-based compound that is not fully digested in the human gut.
It is a type of carbohydrate, that falls under the complex carbs category.
I'm not joking.
Carbohydrates are an umbrella term that include simple carbs and complex carbs.
Simple carbs are carbs typically found in processed or refined sugars that are broken down extremely quickly by the body (examples: corn syrup, sugar, fruit juice concentrate, honey, refined sugars in pastries, cookies, cereal, etc).
Complex carbs on the other hand are carbs made up of longer, complex chains of sugar molecules that take longer to digest (examples: beans, oats, buckwheat, leafy greens, carrots, apples, potatoes, etc).
Different Types of Fiber and its Health Benefits
There are two types of fiber- soluble and insoluble fiber.
There are benefits that apply across the board for both, and also specific benefits that soluble and insoluble fiber each provide. These are all detailed below.
Properties of Soluble Fiber vs Insoluble Fiber
Soluble Fiber can be metabolized in the stomach by gut bacteria which produces short-chain fatty acids. Soluble fiber dissolves in water, where it will form a thick gel-like substance in your stomach.
Insoluble Fiber cannot be broken down by the body. Insoluble fiber doesn’t dissolve in water, instead, it stays relatively intact.
Function and Benefits
FIBER (AS A WHOLE)
Adds bulk to our diet which increases satiation - helps us to feel fuller for longer
Slows digestion - by slowing down the rate at which carbs are absorbed into our bloodstream. This helps regulate our blood glucose and prevent rapid rises in blood sugar after a carbohydrate-containing meal.
Slows down the digestive process by delaying gastric emptying.
Improves glycemic control, blood pressure, and lipid profile (LDL cholesterol, triglycerides and total cholesterol)
Has benefits on colonic health, by aiding in the bulking of the stool which helps promote healthy and regular bowel movement and reduces constipation.
Probably the most pressing reason
Apart from the reasons listed above, what makes fiber so important is the simple fact that we do not get enough of it in our diets currently.
The foods which make up almost half of our daily intake include refined sugars, oils, dairy products, and alcohol, all of which contain zero fiber.
Keeping in mind that dietary fiber comes only from plant-based foods, it’s very easy to see that fiber intake is something that a lot of us are lacking in our diets currently.
Staggering stats show that Americans consume about 15 grams of fiber per day, on average (17.8 g for males and 13.6 g for females).
This is way below the current research which puts the minimum fiber intake suggestion, at between 25 to 29 grams per day, for the purpose of lowering the risk of all-cause and cardiovascular related mortality and incidence of coronary heart disease, stroke, type 2 diabetes, colorectal cancer.
The amount of fiber you need should vary proportionately to your current calorie intake. As a general rule of thumb, the recommended dietary intake for both children and adults stands at at least 14 grams of fiber per 1000 kcal. So if you’re eating 2000 calories, you should be eating at least 28 grams of fiber per day.
Dietary Fiber and Its Impact on Weight and Fat Loss
All things equal, fiber intake has an inverse relationship with body weight and body fat.
Dietary fiber aids in weight management primarily by promoting satiation which helps you feel
fuller longer causing you to eat less.
It also decreases the absorption of macronutrients as insoluble fiber particularly cannot be fully digested, meaning the body is not able to absorb any energy from it. This sounds counterintuitive, but it's a good thing when we are trying to control calorie intake.
And lastly, fiber helps to regulate the gut microbiota.
Interestingly, studies also show that normal weight adults tend to consume more fiber and fruit than their age and height matched overweight and obese counterparts.
This is all well and good, but it’s easy to lose sight of the forest for the trees.
Remember when it comes down to it, losing weight requires being in a calorie deficit.
You could eat all the fiber in the world, but if you are not in a calorie deficit, you will still not lose any weight.
That said, when you are intentionally filling your meals with fiber rich foods, and of course when you are managing your calorie balance, you are doing yourself a massive favor and setting yourself up for future success.
This is because you are practicing the habit of “stretching your calorie dollar” (I’m coining this phrase- essentially, getting the most satiation and fullness for less calories.)
And since fiber-rich foods, such as whole grains, vegetables, fruits, also tend to be micronutrient-dense foods filled with vitamins and minerals, you are essentially nailing down one big component of good nutrition- food quality.
All this backs up the strong link between fiber intake and adherence to macronutrient prescriptions and as a result, diet success.
Should you Count the Calories in Fiber?
A few myths to correct here.
Contrary to popular belief, fiber is not “calorie-free”.
While insoluble fibers cannot be digested in the human stomach, soluble fibers can.
This means that the body cannot extract any energy from insoluble fiber, but for every gram of soluble fiber you eat, roughly 1.5-2.5 calories per gram is extracted. Yes, this is still less than 4 calories per gram for carbohydrates in general, but this is still not zero or free.
Vegetables are also not “negative calorie foods”.
Many people think that it takes more energy to consume and digest vegetables than the energy that can be extracted from it. This is simply not true.
This is also exacerbated by many diet plans that consider vegetables “free foods” that can be eaten without limit.
I recognize the intention behind these statements, but as I always say, obsession without the base of knowledge doesn’t lead to effective and sustainable results.
It’s important to distinguish that even among vegetables, there are differences.
Yes, no doubt all vegetables are good for you.
But they aren’t created equal from a calorie stand point.
An easy way to think of this is that there are two main categories of vegetables- starchy and fibrous.
Starchy vegetables contain a decent amount of carbohydrates and calories per serving. Examples include carrots, pears, and corn. (Potatoes, sweet potatoes, pumpkin are actually vegetables but they are better considered as starches alongside bread, rice, pasta, oatmeal).
Fibrous vegetables contain mostly fiber and some digestible carbohydrates, and contain very little calories.
Examples include romaine lettuce, kale, chard, spinach, zucchini, mushrooms, asparagus, celery, bell peppers, cruciferous vegetables like broccoli, brussel sprouts, etc.
This means that even if you think you are making healthy switches and conscious choices, it is not uncommon for dieters to consume large amounts of starchy vegetables to curb hunger but fail to realize that these also contain considerably more carbohydrate content than their fibrous counterparts.
Doing so may effortlessly eradicate any calorie deficit they think they have created as well.
Now that we have a fuller understanding, I want to point out the very obvious fact that it is extremely difficult to overeat vegetables.
The last thing I want you to walk away with is the idea that you should worry about eating vegetables.
I hope it’s clear that the desire behind sharing all this with you is for greater awareness and education and not to instill fear!
But let’s also not forget that when we douse our vegetables with high-fat and high-calorie toppings, it’s very easy for the calories to add up quicker than I can say “quick”!
I could go on, but lets’ tie up this section here- fiber is not calorie-free, vegetables aren’t negative calories, not all vegetables contain the same amount of carbs, and remember to pay attention to what you are cooking or eating your vegetables with.
Simple Ways to Increase your Fiber Intake
Now that we have laid down all the fundamentals, here are simple, practical ways you can begin to implement to increase your fiber intake.
1. Opt for whole grain options wherever possible- like wholewheat, wholemeal, or granary breads, wholewheat pasta, bulgur wheat, brown rice, quinoa, rolled oats, buckwheat, millet. 2. Limit consumption of refined food products- things that are made with flour like cakes, chips, muffins, crackers. 3. Eat more fruits with their skin on. 4. Add beans and legumes like kidney beans, pinto beans, black beans, lentils, chickpeas to your meals. An easy way is to toss it into stews, curries, salads. 5. Add some nuts and seeds.
Top 20 Sources of Fiber
Split peas- 16.3g/cup
Dried Figs- 14.6g/cup
Black beans- 15g/cup
Lima beans 13.2g/cup