Prebiotics are types of dietary fiber that feed the friendly bacteria in your gut.
This helps the gut bacteria produce nutrients for your colon cells and leads to a healthier digestive system ().
Some of these nutrients include short-chain fatty acids like butyrate, acetate and propionate ().
These fatty acids can also be absorbed into the bloodstream and improve metabolic health ().
However, prebiotics should not be confused with probiotics. For more, read this article that explains the differences.
Here are 19 healthy prebiotic foods.
Chicory root is popular for its coffee-like flavor. It's also a great source of prebiotics.
Approximately 47% of chicory root fiber comes from the prebiotic fiber inulin.
The inulin in chicory root nourishes the gut bacteria, improves digestion and helps relieve constipation (, ).
It can also help increase bile production, which improves fat digestion ().
Additionally, chicory root is high in antioxidant compounds that protect the liver from oxidative damage ().
Bottom Line: Chicory root is often used as a caffeine-free replacement for coffee. Its inulin fiber promotes gut bacteria, reduces constipation and helps break down fat.
Dandelion greens can be used in salads and are a great source of fiber.
They contain 4 grams of fiber per 100-gram serving. A high portion of this fiber comes from inulin (7).
The inulin fiber in dandelion greens reduces constipation, increases friendly bacteria in the gut and boosts the immune system ().
Dandelion greens are also known for their diuretic, anti-inflammatory, antioxidant, anti-cancer and cholesterol-lowering effects (, , , ).
Bottom Line: Dandelion greens are a great fiber-rich substitute for greens in your salad. They increase the friendly bacteria in your gut, reduce constipation and boost your immune system.
The Jerusalem artichoke, also known as the "earth apple," has great health benefits.
It provides about 2 grams of dietary fiber per 100 grams, 76% of which comes from inulin (13).
Jerusalem artichokes have been shown to increase the friendly bacteria in the colon even better than chicory root ().
Additionally, they help strengthen the immune system and prevent certain metabolic disorders (, ).
The Jerusalem artichoke is also high in thiamine and potassium. These can help your nervous system and promote proper muscle function (13).
Bottom Line: Jerusalem artichoke can be eaten cooked or raw. It helps boost your immune system and prevent metabolic disease.
Garlic is an incredibly tasty herb linked to various health benefits.
About 11% of garlic's fiber content comes from inulin and 6% from a sweet, naturally occurring prebiotic called fructooligosaccharides (FOS).
Garlic acts as a prebiotic by promoting the growth of beneficial Bifidobacteria in the gut. It also prevents disease-promoting bacteria from growing (17).
Garlic extract may be effective for reducing the risk of heart disease, and has shown antioxidant, anti-cancer and antimicrobial effects. It may also have benefits against asthma (, 19, ).
Bottom Line: Garlic gives great flavor to your foods and provides you with prebiotic benefits. It has been shown to help promote good bacteria and prevent harmful bacteria from growing.
Onions are a very tasty and versatile vegetable linked to various health benefits.
Similar to garlic, inulin accounts for 10% of the total fiber content of onions, while FOS makes up around 6% (, 22).
FOS strengthens gut flora, helps with fat breakdown and boosts the immune system by increasing nitric oxide production in cells (, , ).
Onions are also rich in the flavonoid quercetin, which gives onions antioxidant and anticancer properties.
Furthermore, onions have antibiotic properties and may provide benefits for the cardiovascular system (, ).
Bottom Line: Onions are rich in inulin and FOS, which can help boost your immune system, provide fuel for your gut bacteria and improve digestion.
Leeks come from the same family as onions and garlic, and offer similar health benefits.
Leeks contain up to 16% inulin fiber (22).
Thanks to their inulin content, leeks promote healthy gut bacteria and help in the breakdown of fat ().
Leeks are also high in flavonoids, which support your body's response to oxidative stress ().
Bottom Line: Leeks are often used in cooking for their distinct flavor. They are high in prebiotic inulin fiber and vitamin K.
Asparagus is a popular vegetable and another great source of prebiotics.
The inulin content may be around 2-3 grams per 100-gram (3.5-oz) serving.
Asparagus has been shown to promote friendly bacteria in the gut and has been linked to the prevention of certain cancers ().
The combination of fiber and antioxidants in asparagus also appears to provide anti-inflammatory benefits ().
A 100-gram (3.5-oz) serving of asparagus also contains about 2 grams of protein.
Bottom Line: Asparagus is a spring vegetable rich in prebiotic fiber and antioxidants. It promotes healthy gut bacteria and may help prevent certain cancers.
Bananas are very popular. They're rich in vitamins, minerals and fiber.
Bananas contain small amounts of inulin.
Unripe (green) bananas are also high in resistant starch, which has prebiotic effects.
The prebiotic fiber in bananas has been shown to increase healthy gut bacteria and reduce bloating (, , ).
Bottom Line: Bananas are rich in fiber. They're also great at promoting healthy gut bacteria and reducing bloating.
Barley is a popular cereal grain and is used to make beer. It contains 3–8 grams of beta-glucan per 100-gram serving.
Beta-glucan is a prebiotic fiber that promotes the growth of friendly bacteria in the digestive tract (, 33, ).
The beta-glucan in barley has also been shown to lower total and LDL cholesterol, and may also help lower blood sugar levels (, , , ).
Bottom Line: Barley is high in beta-glucan fiber, which promotes healthy bacteria in the gut. It also seems to lower cholesterol and blood sugar levels.
Whole oats are a very healthy grain with prebiotic benefits. They contain large amounts of beta-glucan fiber, as well as some resistant starch.
Beta-glucan from oats has been linked to healthy gut bacteria, lower LDL cholesterol, better blood sugar control and reduced cancer risk (, , , , ).
Furthermore, it has been shown to slow digestion and help control appetite (, ).
Oats also offer antioxidant and anti-inflammatory protection due to their phenolic acid content (, ).
Bottom Line: Whole oats are a grain rich in beta-glucan fiber. They increase healthy gut bacteria, improve blood sugar control and may reduce cancer risk.
Apples are a delicious fruit. Pectin accounts for approximately 50% of an apple's total fiber content.
The pectin in apples has prebiotic benefits. It increases butyrate, a short-chain fatty acid that feeds the beneficial gut bacteria and decreases the population of harmful bacteria (, ).
Apples are also high in polyphenol antioxidants.
Combined, polyphenols and pectin have been linked to improved digestive health and fat metabolism, decreased levels of LDL cholesterol and a reduced risk of various cancers (, , , , ).
Apples also have antioxidant and anti-inflammatory properties (, , ).
Bottom Line: Apples are rich in pectin fiber. Pectin promotes healthy gut bacteria and helps decrease harmful bacteria. It also helps lower cholesterol and reduces cancer risk.
Konjac root, also known as elephant yam, is a tuber often used as a dietary supplement for its health benefits.
This tuber contains 40% glucomannan fiber, a highly viscous dietary fiber.
Konjac glucomannan promotes the growth of friendly bacteria in the colon, relieves constipation and boosts your immune system (, ).
You can consume it in the form of foods made with the konjac root, such as shirataki noodles. You can also take glucomannan supplements.
Bottom Line: The glucomannan fiber found in konjac root helps promote friendly bacteria, reduces constipation, boosts the immune system, lowers cholesterol in the blood and helps with weight loss.
Cocoa beans are delicious and very healthy.
The breakdown of cocoa beans in the colon produces nitric oxide, which has beneficial effects on the cardiovascular system ().
Cocoa is also an excellent source of flavanols.
Flavanol-containing cocoa has powerful prebiotic benefits associated with the growth of healthy gut bacteria. It also has benefits for the heart (, , , ).
Bottom Line: Cocoa is a tasty prebiotic food. It contains flavanols that increase healthy gut bacteria, lower cholesterol and improve heart health.
Burdock root is commonly used in Japan and has proven health benefits.
It contains about 4 grams of fiber per 100-gram (3.5-oz) serving, and the majority of this is from inulin and FOS.
Inulin and FOS from burdock root have prebiotic properties that can inhibit growth of harmful bacteria in the intestines, promote bowel movements and improve immune function ().
Burdock root also has antioxidant, anti-inflammatory and blood sugar lowering properties (, , , ).
Bottom Line: Burdock root is widely consumed in Japan. It has been shown to promote healthy bowel movements, inhibit the formation of harmful bacteria in the colon and boost the immune system.
Flaxseeds are incredibly healthy. They're also a great source of prebiotics.
The fiber content of flaxseeds is 20–40% soluble fiber from mucilage gums and 60–80% insoluble fiber from cellulose and lignin.
The fiber in flaxseeds promotes healthy gut bacteria, promotes regular bowel movements and reduces the amount of dietary fat you digest and absorb (, ).
Because of their content of phenolic antioxidants, flaxseeds also have anti-cancer and antioxidant properties and help regulate blood sugar levels (, ).
Bottom Line: The fiber in flaxseeds promotes regular bowel movements, lowers LDL cholesterol and reduces the amount of fat you digest and absorb.
Yacon root is very similar to sweet potatoes and is rich in fiber. It is particularly rich in prebiotic fructooligosaccharides (FOS) and inulin.
The inulin in yacon has been shown to improve gut bacteria, reduce constipation, enhance the immune system, improve mineral absorption and regulate blood fats (, , ).
Yacon also contains phenolic compounds that give it antioxidant properties (, ).
Bottom Line: Yacon root is rich in inulin and FOS. It is great at promoting digestive health, improving mineral absorption, enhancing your immune system and regulating blood fats.
Jicama root is low in calories and high in fiber, including the prebiotic fiber inulin.
Jicama root helps improve digestive health, enhance insulin sensitivity and lower blood sugar levels (, ).
Additionally, it is high in vitamin C, which stimulates the immune system to fight illnesses ().
This plant also offers an excellent balance of all the essential amino acids ().
Bottom Line: Jicama root is low in calories, but rich in inulin. It can improve your gut bacteria, promote better blood sugar control and provide antioxidant protection.
Wheat bran is the outer layer of the whole wheat grain. It is an excellent source of prebiotics.
It also contains a special type of fiber made of arabinoxylan oligosaccharides (AXOS).
AXOS fiber represents about 64–69% of wheat bran's fiber content.
AXOS fiber from wheat bran has been shown to boost healthy Bifidobacteria in the gut (, , ).
Wheat bran has also been shown to reduce digestive problems such as flatulence, cramping and abdominal pain (, ).
Grains rich in AXOS also have antioxidant and anti-cancer effects (, ).
Bottom Line: Wheat bran is rich in AXOS, a type of fiber that has been shown to increase healthy gut bacteria and reduce digestive problems.
Seaweed (marine algae) is rarely eaten. However, it is a very potent prebiotic food.
Approximately 50–85% of seaweed's fiber content comes from water-soluble fiber (, 93).
The prebiotic effects of seaweed have been studied in animals but not in humans.
Nonetheless, these studies have shown that seaweed may provide many healthy benefits.
They may enhance the growth of friendly gut bacteria, prevent the growth of disease-causing bacteria, boost immune function and reduce the risk of colon cancer ().
Seaweed is also rich in antioxidants that have been linked to the prevention of heart attacks and strokes ().
Bottom Line: Seaweed is a great source of prebiotic fiber. It can increase the population of friendly bacteria, block the growth of harmful bacteria and enhance immune function.
Prebiotic foods are high in special types of fiber that support digestive health.
They promote the increase of friendly bacteria in the gut, help with various digestive problems and even boost your immune system.
Prebiotic foods have also been shown to improve metabolic health and even help prevent certain diseases.
However, some of the fiber content of these foods may be altered during cooking, so try to consume them raw rather than cooked.
Do yourself and your gut bacteria a favor by eating plenty of these prebiotic foods.