We’ve heard the old adage: Fiber is good for you. Also known as roughage or bulk, dietary fiber has many benefits, ranging from optimal digestion to reduced body weight and improved metabolic health.
But what types of fiber are there? How much fiber do we need in a day, and which foods are the best sources of fiber? Here’s everything you need to know about fiber and how to get more. We’ll also dive into some studies that support its favorable effects.
Table of Contents
What Is Fiber?
Fiber makes up the structure of plants. It is a carbohydrate that cannot be digested by your body. Unlike other carbs that get broken down into glucose, fiber doesn’t serve as a fuel source. However, it plays an essential role in lowering your risk of diseases.
Moreover, fiber comes in two categories, namely:
This type of fiber dissolves in water and creates a gel-like material to help with digestion, making it easier for stool to pass through. Most of the benefits of fiber, such as reducing glucose and cholesterol levels, are attributed to soluble fiber.
Examples of foods high in soluble fiber include avocados, brussels sprouts, broccoli, sweet potatoes, apples, carrots, flaxseeds, and hazelnuts.
Insoluble fiber does not dissolve in water, but it also appears to facilitate the passage of foods through your digestive system, thereby helping relieve constipation.
It’s commonly found in the skin of fruits like apples and bananas, green beans, cauliflower, berries (e.g., blueberries, blackberries, strawberries), potatoes, sweet potatoes, and nuts (e.g., almonds, pistachios, peanuts).
Why Is Dietary Fiber Important?
We’ve come to appreciate fiber for its role in digestion. But what other benefits are there? Here are some of the things that happen when you eat more fiber:
Controls body weight
Studies have shown that adding more fiber to your diet is associated with improved satiety, which results from the slowed absorption of nutrients, such as fat. Feeling satiated or full is important for controlling your appetite. As a result, you’re less likely to overeat or even snack in between meals.
One 2019 study involving 345 participants also found that fiber promotes weight loss and adherence to a diet regardless of macronutrients (carbs, fats, protein) and calorie intake in people who are overweight or obese.
If you’re constantly struggling with cravings and frequent snacking, a higher-fiber diet might be what you need.
Manages blood sugar
For people with pre-diabetes or diabetes, fiber (particularly soluble fiber) balances blood sugar and lowers insulin levels. Soluble fiber does this by delaying the absorption of sugar from foods. Additionally, it removes excess glucose from your body.
According to a meta-analysis, researchers found that consuming at least 13 grams of soluble fiber daily, considered a median dose, resulted in significantly lower HbA1c levels.
Note that HbA1c or glycated hemoglobin indicates blood sugar control over the past 3 months. By maintaining normal HbA1c levels, you’re also doing your heart a favor!
🤓Read more: Pick These Foods to Improve Your Diabetes!
When we hear “cholesterol” we often assume that having high cholesterol numbers is bad. However, high levels of HDL are considered good for you.
Here’s a quick overview to clear up any misconceptions:
- LDL (low-density lipoprotein) cholesterol has a reputation for being bad, but it’s important to note that LDL consists of different sizes:
- Small dense LDLs drive inflammation and are considered an emerging risk factor for type 2 diabetes and cardiovascular disease. Small dense LDLs are also associated with high triglycerides and low HDL levels.
- Larger, less dense LDLs are considered less dangerous since they’re unlikely to penetrate the arterial wall, although most healthcare providers do not rely on LDL particle size to decide on their treatment plan.
- HDL (high-density lipoprotein) cholesterol is considered the “good” cholesterol because it keeps the inner walls of your blood vessels clean, preventing plaque buildup or atherosclerosis.
- Triglycerides are the type of fat that makes you prone to serious health problems when elevated. They increase when you consume high amounts of simple sugars and processed foods. Besides heart disease, high triglycerides put you at risk for pancreatitis and stroke.
Research has found a dose-response relationship between fiber intake and HDL cholesterol. When participants increased their fiber intake from 18 grams to 30 grams daily, their HDL levels also increased by 10.1%.
In another study involving 117 overweight and obese adults, more fiber in their diet was linked to lower triglycerides. The same study mentioned how fiber decreases insulin resistance, a driver of hypertriglyceridemia and low HDL levels.
Increases gut microbiome diversity.
All the microbes in your gut (collectively known as the gut microbiome) play many roles, ranging from metabolism to protection against harmful microorganisms.
Although it’s challenging to define a healthy gut microbiome, researchers agree that a more diverse microbiome benefits your health.
In contrast, decreased diversity and dysbiosis (the imbalance of your microbiome composition) are linked to various health problems, such as:
- Inflammation, which can increase the risk of cancer
- Type 2 diabetes
- Neurodegenerative disorders (e.g. Alzheimer’s and Parkinson’s)
To promote microbiome diversity, it’s a good idea to include a diverse selection of fibers in your diet. Don’t overthink it — just make sure you’re eating soluble and insoluble fiber from various sources.
🤓Read more: The Microbiome: Unlocking the Key to Health
Protects against cholesterol gallstones
For those who are likely to develop gallstones, fiber offers protection.
Individuals at risk include those overweight or obese, women, over 60 years old, those taking cholesterol-lowering drugs, eating a diet high in refined carbohydrates, and who have undergone rapid weight loss.
Fiber prevents gallstones from forming by speeding up the movement of food through your intestine. It also reduces the production of secondary bile acids that promote gallstone formation.
Fiber: How Much and Ways to Eat More
The Mayo Clinic recommends at least 21 to 25 grams of fiber a day for women and 30 to 38 grams a day for men. As an example, 30 grams of fiber would look like this:
- One cup of broccoli (5 grams of fiber)
- One ounce of chia seeds (10 grams of fiber)
- One cup of baked beans (10 grams of fiber)
- A medium-sized pear (5.5 grams of fiber)
Below, you’ll find helpful tips to start boosting your fiber intake…
Prioritize whole foods over fiber supplements
This does not mean that fiber supplements are totally off-limits. But you should strive to get fiber from whole food sources because they’re rich in micronutrients — vitamins and minerals your body needs for essential functions.
There are so many high-fiber foods to choose from: avocados, artichokes, brussels sprouts, lentils, kidney beans, almonds, chickpeas, and so much more.
However, if you find it difficult to meet your daily fiber intake through food, you may consider supplementation. Be sure to consult a healthcare provider before taking fiber supplements.
Eat fruits and veggies in season
Different seasons produce different fresh produce. For example, summer is a great time to enjoy apples, bananas, and blueberries, while fall is for lettuce and parsnips.
Check out this seasonal produce guide by the US Department of Agriculture.
When fruits and vegetables are in season, they’re tastier and have higher nutritional values. For those who are trying to reduce food cost without sacrificing quality, seasonal produce are cheaper!
Snack on nuts and seeds
Quit snacking on potato chips and have nuts and seeds as a nutrient-dense, high-fiber option before your next meal. Snack on them alone or toss some into your salad to add crunch. Try almonds, macadamias, sunflower seeds, and pumpkin seeds.
Have some berries for dessert
Another great tip for boosting your fiber intake, at the same time satisfying your sweet tooth in a healthy way, is to eat berries.
Here are examples of berries and their fiber content in a 100-gram serving:
- Strawberries: 2 grams of fiber
- Blueberries: 2 grams of fiber
- Raspberries: 6.5 grams of fiber
- Blackberries: 5 grams of fiber
Since berries are naturally sweet, there’s no need to use a sweetener. Feel free to experiment with mixed berry smoothies!
Always check the nutrition facts label
You won’t find labels on most natural foods at the groceries. However, for packaged foods, the nutrition facts label is helpful for knowing how much fiber you’ll get. “Dietary Fiber” is listed underneath “Total Carbohydrate” since fiber is a type of carbohydrate.
Don’t forget to check the serving size and number of servings per container. That way, you will know whether you’re getting enough fiber from a pack. High-fiber packaged foods that can be kept in your pantry for busy days include granola clusters, roasted chickpeas, and dried fruits (beware of the sugar content, though).
Bonus tip: Those keeping their carbs under control for blood sugar management and weight loss can subtract dietary fiber from total carbohydrates to get the net carbs of a packaged food.
You’ve just learned how important fiber is for digestion, weight management, and metabolic health. While following the tips shared above, remember to slowly increase your fiber intake. As with any dietary change, a sudden shift may lead to bloating and other digestive issues.
If you’re in doubt or have questions about increasing your fiber intake not discussed in this article, feel free to leave a comment below. Also, reach out to a dietician who can come up with a plan that works for you. For more nutrition tips, visit Your Health Forum’s Nutrition and Natural Food Recipes section.
Tiffany Joy Yamut, RN.
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