Maybe it’s time to grab an extra helping of greens, top your breakfast with berries, or dust off your blender. Most Americans don’t get enough fiber. A sin, Less than 5%. We are incredibly deficient (and experts are concerned). While this is shocking, it’s not entirely surprising. After all, the standard American diet is virtually devoid of fiber. We are obsessed with carbohydrates and proteins, but we overlook the tiny but mighty impact of fiber. And so, we are superfed but undernourished. Without further ado, let’s break down what fiber is, how to get it, and the benefits of a high fiber diet.
Featured Image by Joann Pai.
What is fiber?
Fiber is a type of carbohydrate. It includes a broad spectrum of plant materials (polysaccharides, pectin, guar gum, etc.) that the body cannot digest. But more carbohydrates are broken down into sugar molecules, fiber is an outlier. Instead, fiber passes through the body undigested. It comes with the ride, but that’s a good thing! The fact that it is not digested is precisely why it is so important. Fiber helps minimize constipation, regulates hunger cues, maintains blood sugar in check, slows glucose absorption, promotes heart health, and more. The FDA has a helpful and easy-to-digest guide to fiber here.
Two types of fibres, two different roles
There are two types of fibers. Both are essential, but each plays a different role in our health:
Fiber that dissolves in water. Soluble fibers are derived from gums and pectins. It turns into a thick, jelly-like gel when it dissolves in water. This gel helps reduce cholesterol levels, especially LDL. Soluble fiber also helps lower glucose levels. It is found in chia seeds, beans, fruits, carrots, oats, etc.
Fiber that does not dissolve in water. Insoluble fiber helps prevent constipation and keeps things moving. Insoluble fiber is found in whole wheat flour, cauliflower, almonds and potatoes.
Sources of fiber
Fiber is mainly found in fruits, vegetables, nuts, seeds, grains and legumes. A good rule of thumb: Whole, colorful foods are often high in fiber. Just another reason to eat the rainbow! Cooked or raw, the products are an incredible source of fiber. However, studies show that for the greatest fiber retention, eat your vegetables raw (or as close to raw as possible). Cooking your vegetables, by boiling, roasting, etc., can reduce the fiber content by almost half. This is useful if you are new to fiber consumption! Ultimately, the biggest bang for your nutrition buck is filling up on mostly raw veggies. Through trial and error you will find what works best for your body.
Foods high in fiber or low in fiber
Before we dive into the benefits of a high fiber diet, let’s distinguish between high fiber foods and low fiber foods. For context, here is a short list of high-fiber foods, along with their approximate fiber content:
- One cup of edamame: 18 grams
- A cup of lentils: 16 grams
- A cup of black beans: 15 grams
- A cup of chickpeas: 12 grams
- Two tablespoons of chia seeds: 10 grams
- A cup of raspberries: 8 grams
- Half cup of raw pistachios: 7 grams
- One persimmon: 6 grams
- A cup of broccoli: 5 grams
- Half cup of avocado: 5 grams
On the contrary, they are foods low in fiber
- Refined carbohydrates, such as white flour pancakes, bagels, bread, pasta, and white rice.
- Animal protein.
- Dairy products.
- Low-fiber packaged products, such as cereals, chips, crackers and granola bars.
- Most desserts, such as traditional cookies, donuts and cakes.
- Sodas and other sugary drinks.
Why aren’t Americans getting enough fiber?
When we talk about the pitfalls of the American diet, we tend to focus on our excess amounts of processed sugar, table salt, and nutrient-devoid calories. Thus, we neglect to talk about fiber. There’s a nuance to its absence, but it mostly comes down to what we’re exposed to. The traditional American diet lacks fiber. In addition, what is offered to us in gas stations and fast food restaurants does not make things easier. We got stuck in the fiber gap.
Centuries ago, it was not like that. The human species has traditionally evolved to eat fiber, in large quantities. Long before we learned to domesticate animals, we lived primarily on fiber-rich fruits, roots, shoots, nuts, and seeds.
How much fiber do you need each day?
It’s up for debate. However, a growing body of research shows that official recommendations (less than 30 grams/day) may be less than what we really need for optimal health. What we really need may be 50 grams/day (or more). Currently, the average American consumes 10-15 grams of fiber per day, way off the mark. Let these stats let you add more fiber, stat.
Does a low fiber diet cause disease?
Yes. A lack of fiber can cause more than constipation. In fact, it can cause a host of unwanted diseases (and even cancer). A lack of fiber can mean an unhealthy digestive system, which can lead to short- and long-term health complications. Low fiber diets have been linked to everything from colon cancer to unhealthy cholesterol levels, a weakened immune system and obesity.
How to Slowly Eat More Fiber
It is not necessary to do a complete detox– unless it speaks to you, of course! Consider instead the notion of “crowding out”. The more fiber-rich ingredients you add to your plate, the more you will naturally crowd out processed and nutrient-devoid foods.
Enjoy meal prep.
Start preparing your meals by making more plant-based foods. You’ll be much more likely to opt for foods with fiber when they’re ready to eat (and easy to see). Take a look at these fiber-rich recipes for inspiration.
Rather than adding fiber-rich foods all at once, add 1-2 servings per day to your regular diet. Do this for a week, let your body adjust, then add another serving the following week.
Consider simple exchanges.
To show creativity.
Food is fun! Enjoy an alternative breakfast on the weekend, like this beautiful (and functional) breakfast board. Eating more fiber doesn’t require pounding wheat bran.
Benefits of a high fiber diet
They are a dime a dozen. Eating more fiber helps normalize bowel movements, maintains gut health (reducing your risk of hemorrhoids, for example), lowers cholesterol levels, controls blood sugar levelshelps achieve a healthy weight and promotes longevity.
- Helps control blood sugar levels. In people with diabetes, fiber, especially soluble fiber, can slow the absorption of sugar and help improve blood sugar levels. A healthy diet that includes insoluble fiber may also reduce the risk of developing type 2 diabetes.
- Helps achieve a healthy weight. High-fiber foods tend to be more filling than low-fiber foods, so you’re likely to eat less and stay full longer. And fiber-rich foods tend to take longer to eat and to be less “energy dense,” meaning they contain fewer calories for the same volume of food.
- Helps you live longer. Studies suggest that increasing your dietary fiber intake, especially grain fiber, is associated with a reduced risk of dying from cardiovascular disease and all cancers.
Relief from chronic constipation
According to this article, a high-fiber diet significantly outperformed placebo for relief of chronic constipation. In other words: the fiber keeps everything moving. And who doesn’t want to be regular? Dietary fiber softens your stools, making them easier to pass.
We have trillions of bacteria living in and around the human digestive tract. They need fiber! Bacteria feed on it. When there is no fiber to eat, some forms of gut bacteria turn to the lining that protects the colon, which is not good. Basically, the fiber retains pro-inflammatory cells in check, improving overall gut health.
Studies have shown that a high fiber diet probably reduces the risk of colorectal cancer. In addition to helping prevent other diseases, fiber is essential for heart health. Soluble fiber can help lower levels of low-density lipoprotein (LDL), or “bad” cholesterol. Studies also showed that high-fiber foods may have other heart health benefits, such as reducing blood pressure and inflammation.
Healthier body weight
Fiber promotes feelings of fullness more effectively than low-fiber and/or processed foods. In turn, it is shown in to research to support weight loss. This is a win-win situation, as increasing fiber intake will naturally encourage the replacement of less healthy foods with natural, plant-based alternatives. Although weight loss is not the primary goal of a high fiber diet, most people do end up losing a small (or moderate) amount of weight after increasing their fiber intake.
Improve insulin sensitivity
Linked to the prevention of heart disease, fiber helps ward off insulin resistance. It is estimated that 88% of Americans are metabolically unhealthy. Fiber can dramatically reverse these statistics. Time and again, fiber has been proven to work keep blood sugar levels lower during the day. Essentially, fiber “dilutes” sugars, causing them to take longer to be absorbed into the bloodstream.