Study Shows Eating Fiber Is Directly Linked to Better Gut Health—These Are the Top Food Sources
You may have noticed more foods boasting their fiber content on the front label.
Why the sudden interest in roughage?
Recent research has shed light on the numerous benefits of dietary fiber.
Over 70% of our immune system resides in our digestive tract, so keeping it healthy will in turn improve your overall health.
But in order to do that, we need to eat plenty of high-fiber foods to feed the good bacteria in our gut, and to keep things moving along smoothly.
Why Fiber for Gut Health
Fiber has recently been receiving a lot of praise, and for good reason.
We all know that fiber helps support our digestion, and keeps everything moving along regularly.
Most of our immune system resides in our intestines, so fiber may also help our immunity.
It also contributes to the overall health of our small and large intestines.
There are many other health benefits of fiber, from lowering cholesterol levels, reducing the risk for diabetes and obesity, and supporting a healthy weight.
A high-fiber diet may also help with weight loss. Foods high in fiber can contribute to the feeling of fullness.
There are two types of fiber: soluble and insoluble, and you need both.
Soluble fiber absorbs water and turns into a form of a gel, which is the good bacteria in our gut loves.
It slows down digestion, can help us feel fuller longer, and slows down how quickly blood sugar, or glucose, hits the bloodstream.
Soluble fiber can also help with diarrhea.
Foods high in soluble fiber include nuts, seeds, beans, and legumes, as well as oatmeal.
Insoluble fiber is not digested and passes through our system relatively intact.
This provides bulk to our bowel movements. It also passes through the system faster, which keeps us regular.
Insoluble fiber can also help avoid constipation and may help boost your metabolism.
Foods high in insoluble fiber include whole grains, fruits, and vegetables.
If you suffer from irritable bowel syndrome, you might find that a high-fiber diet may help manage your symptoms.
At times of flares, you may want to switch to a low fiber diet until the symptoms subside.
Prebiotics vs Probiotics
You may have heard about probiotics, which are beneficial bacteria that live in our gut and are linked to many health benefits.
You want to have more healthy bacteria than bad bacteria.
Consuming probiotics like bifidobacteria and lactobacillus is a good way to keep a healthy gut microbiome.
Probiotics are the bacteria themselves and can be found in fermented foods like yogurt, kimchi, sauerkraut, miso, kefir, and kombucha.
Prebiotics are the food for these gut bacteria to consume and continue living and thriving in your gut.
Prebiotics are largely made of fiber, most notably soluble fiber.
Foods high in resistant starch, like green bananas, serve as prebiotics too.
Try to include probiotic and prebiotic foods in your diet to keep your gut microbiota and digestive system healthy.
Antibiotic use can impact your gut microbiota, killing off the gut flora and impacting your microbiome and gut health.
When you complete taking an antibiotic, be sure you include probiotics and prebiotics in your diet.
Additionally, consuming too many artificial sweeteners may impact your gut microbiome.
If you choose to use artificial sweeteners, it’s wise to use them in moderation.
How Much Fiber Should You Be Eating?
The U.S. Dietary Guidelines advise that women get 25 grams of fiber per day, and men get 38 grams daily.
Most Americans are only getting about half of that (1,2).
You may want to track what you eat on a typical day to see. if you are getting enough fiber.
Luckily, there are many yummy ways to boost your fiber intake. Fruits, vegetables, whole grains, nuts, and seeds are all great sources.
Here are 10 of the best sources of fiber to reach for:
16 High Fiber Foods for Gut Health
Broccoli
Forget the overcooked green veggie of your past. Broccoli is one of the most nutrient-dense foods out there.
This cruciferous vegetable has vitamin C, K, B, as well as potassium, iron, and antioxidants that fight inflammation.
It also has a high fiber content. Enjoy it steamed, roasted, or in a slaw.
Each cup of broccoli has 2.4 grams of fiber, making this a great way to get more fiber (3).
Oats
This classic breakfast food is classic health food. One cooked cup of oatmeal contains 4.8 grams of fiber.
Typically ½ cup dry yields about 1 cup cooked oatmeal (4).
Oatmeal is noted for its ability to improve your heart health by reducing your cholesterol.
You can top your oats with other fiber-rich rockstars like berries, nuts, and seeds. You can also toss oats into your smoothies, burger patties, or bake into muffins.
Berries
Berries are a sweet topping for oatmeal or yogurt. But they are also nutritional powerhouses.
They have a bevy of vitamins, minerals, polyphenols, and antioxidants that can help tamp down inflammation.
But they also have a high fiber content.
One cup of berries contains about 8 grams of fiber and only 64 calories (5).
You can reap the benefits from raspberries, blueberries, strawberries, or blackberries.
Add them to smoothies or throw them in a salad for a sweet spin.
Legumes
Legumes refer to beans, peas, chickpeas, and pulses.
These pantry staples have been eaten around the world and for good reason.
They can add bulk and flavor to main dishes, as well as sides and salads. They are also one of the most fiber-rich foods available!
Lentils may help lower blood sugar in diabetic patients when eaten in place of other starches (6).
Other beans may help lower LDL or “bad cholesterol” (7).
They contain vitamins, minerals like iron, protein, and very high fiber content.
You get about 7 grams of fiber with every ½ cup of cooked lentils or navy beans.
Peas provide about 4 grams for every ½ cup cooked, as well as vitamin A which is important for eye health. (8, 9)
Throw black beans, kidney beans, or chickpeas into pasta, burgers, burritos, salads, and rice, or mash them into a spread for toast or crackers.
Stew beans or split peas with onions, garlic, and spices to make a healthy main dish.
Popcorn
This well-loved snack for movies is also packed with fiber.
Three cups of air-popped popcorn have 3.6 grams of fiber and only about 100 calories.
The key is to air pop the popcorn to keep from adding poor quality fats and sodium. (10)
Many people enjoy this snack as an alternative to whole-grain crackers, as it has more fiber and fewer calories.
You can sprinkle spices like pepper, cumin, paprika, and garlic powder on popcorn to add more flavor and antioxidants with less salt.
Pears
This fall favorite is a great source of fiber. One medium pear has 6 grams of fiber.
They also have a good dose of vitamin C. And like apples, they will keep well in your fridge for a few weeks (11).
Pair your pear with some cheese or nuts for a balanced snack with healthy fats and protein.
Avocado
If you need another reason to mash up a bowl of guacamole, look no further.
These creamy green cuties are a great way to increase the fiber content in your diet.
Half of an average avocado has 5 grams of dietary fiber or 18% of your daily value (12).
Also, avocados have very healthy fat, monounsaturated fat, like that found in olive oil or fish.
Because avocados are high in fat and calories, you may want to enjoy it in moderation.
Add avocado to your sandwiches, salads, or even your morning smoothie.
Collard Greens
We hear plenty about spinach and kale, but don’t forget about collard greens.
This comforting and delicious Southern side dish has a good amount of fiber.
One cup of cooked collard greens plenty of vitamin K, and they have 2.5 grams of fiber! Try this green veggie sauteed or braised (13).
Brussels Sprouts
Another green vegetable that was deemed yucky after being sadly overcooked, brussels sprouts are nutrition rock stars.
You can enjoy these cruciferous veggies slow-roasted or stir-fried, or even thinly sliced into a slaw.
One cup of cooked Brussels sprouts contains 6 grams of fiber (14).
Chia Seeds
If you ever had a chia pet, you were nurturing a fiber-rich seed!
One ounce of chia seeds (a little under 3 Tbsp) has about 10 grams of fiber.
But these little bitty seeds also contain bone-boosting calcium and are a rich source of omega-3 fatty acids, which are very good for our heart and brain health (15).
You can easily add these to your oatmeal, yogurt, cold cereal, or sprinkled on a salad or soup.
They don’t taste like much of anything, but they do have a slight crunch, so they are perfect to stir into a variety of foods.
You can also soak them overnight in milk to make a healthy pudding that you can top with fruit in the morning.
Almonds
Almonds have been enjoyed for centuries in baked goods and as a snack. Almonds are rich in healthy fats, manganese, magnesium, and vitamin E.
And they are also a good source of fiber. Three tablespoons have 4 grams of dietary fiber and 6 grams of protein (16).
Try these sliced or slivered nuts on your oats or yogurt, or you can toss them into salads, or add to rice pilaf.
Edamame
Next time you are out for sushi or in your grocer’s freezer aisle, get some edamame!
Edamame, or soybeans, contains protein, fiber, and healthy fats.
Every ½ cup of steamed edamame beans has about 5 grams of fiber or 18% of your daily intake (17).
Edamame and tofu may also help lower your heart disease risk due to powerful compounds called isoflavones (18).
These green beans are fun to pop out of their pods to snack on or add to your stir-fry, grain bowls, or salads.
Sweet potato
Think sweet potatoes are only for Thanksgiving? Think again! This tuber is a great source of beta carotene, which helps our vision, as well as B vitamins and minerals.
But these potatoes also have plenty of fiber. A medium sweet potato has 3.6 grams of dietary fiber. (19)
Skip the pool of butter, brown sugar, and marshmallows.
Try these sweet spuds roasted in wedges with steak seasoning, or mash them with cumin, cinnamon, and dried chipotle peppers.
Barley
Don’t skip this whole grain! Barley has a nutty flavor and is small like a grain of rice.
One cup of cooked barley has 6 grams of fiber and 4 grams of protein (20).
Similar to other whole grains like brown rice or quinoa, it makes a great base for grain bowls or tossed into soups, stews, and salads.
Artichokes
These floral-looking veggies have vitamin C, potassium, and are. a good source of fiber. One whole artichoke contains almost 7 grams of your daily fiber.
This vegetable can be trimmed, steamed, and then served with a lemon vinaigrette (21).
Mango
This tropical fruit is chocked full of vitamin C, potassium, and beta carotene.
It also has a good amount of fiber. One mango boasts over 3 grams of fiber, which is about 10% of your recommended daily fiber intake (22).
Enjoy fresh, or slices with yogurt, cereal, or whipped with coconut milk into a smoothie.
Final Take
There are so many delicious ways to increase your fiber intake and get more grams per day with gut-healthy foods.
Research has shown there are numerous benefits to a high-fiber diet, including controlling blood sugar levels, maintaining a healthy digestive system, and reducing cholesterol levels.
High-fiber foods are also linked to keeping your intestines healthy and reducing the risk of colon cancer.
Eating these foods, along with probiotics, are a sure way to have a healthy gut.
Many of these high-fiber foods are readily available in your grocery store and are very affordable.
If you aren’t getting enough fiber, you may consider taking a fiber supplement.
Many fiber supplements use isolated fibers like inulin, which is derived from chicory root, and have been approved by the FDA.
But it is important to remember that fiber supplements do not contain the other vitamins, minerals, polyphenols, and antioxidants present in the foods listed above.
The best way to increase your fiber intake is through these whole foods.
References
- USDA. Dietary Guidelines for Americans, 2020-2025 and Online Materials. https://www.dietaryguidelines.gov/resources/2020-2025-dietary-guidelines-online-materials
- McManus K. Should I be eating more fiber? Harvard Health Blog. Feb 21, 2019. https://www.health.harvard.edu/blog/should-i-be-eating-more-fiber-2019022115927
- USDA FoodData Central. Broccoli, Raw. https://fdc.nal.usda.gov/fdc-app.html#/food-details/1103170/nutrients
- USDA FoodData Central. Oatmeal, multigrain, no fat added. https://fdc.nal.usda.gov/fdc-app.html#/food-details/1101614/nutrients