What Are Prebiotics & How to Get More of Them In Your Diet


Over the last decade, probiotic supplements and certain fermented probiotic foods – like yogurt, kefir, kombucha, sauerkraut, and kimchi – have become wildly popular due to the health benefits that come from supporting a healthy gut microbiome.

That’s good news. Our gut health can suffer due to factors such as stress, antibiotic use, and poor diet, all of which can reduce the population of good bacteria in the gut, causing bacterial imbalances and other negative effects.

Probiotics offer one way to help restore the gut’s microbial balance, but there’s another.

Enter prebiotics.

What Are Prebiotics?

Prebiotics are carbohydrates, often dietary fibers, that help feed the beneficial bacteria in your gut. So, rather than restocking the gut with good bacteria, prebiotics feed the good bugs already present in your gut and help them flourish.

Science defines a prebiotic as “a substrate that is selectively utilized by host microorganisms conferring a health benefit.”

Usually, a substrate is a soluble fiber.

Dietary Fibers

Dietary fibers can be split into two categories: soluble fiber, which is fermented by gut bacteria, and insoluble fiber, which isn’t fermentable and acts as roughage. While all prebiotics are soluble fiber, not all soluble fibers are prebiotics because they aren’t all metabolized by beneficial gut microbes.

Most of the research conducted so far focuses on prebiotics that influence the most prevalent gut microorganisms (namely well studied probiotics like Lactobacillus helveticus Strain R0052 and Bifidobacterium longum Strain R0175). These prebiotics are classified as fructooligosaccharides (FOS), galactooligosaccharides (GOS) and inulin (a type of FOS).

How Prebiotics Work

Research on prebiotics is both new and very promising, showing a host of benefits.

Here’s what we know so far.

Your good gut bacteria turns prebiotic fiber into a short-chain fatty acid called butyrate, which promotes colon health and supports the health of the epithelial defense barrier. In fact, studies suggest that butyrate production in the colon cannot be maintained without adequate intakes of prebiotic fiber.

Research also suggests that prebiotics may help digestion; enhance the bioavailability and uptake of minerals such as calcium, magnesium, and potentially iron; support cardiovascular health; and promote satiety and healthy blood sugar levels, as well as support immune health.

Best Prebiotic Foods, Supplements and More

Prebiotic supplements are growing in popularity. Prebiotics are now being added to everything from energy bars, to beverages, to baked goods. Many medical professionals believe you can get all the prebiotics you need from a healthy diet.

12 Prebiotic-Rich Foods to Help Boost Your Gut Health

Best Prebiotic Foods to Eat for Gut Health | What Are Prebiotics?


  1. Seaweed

It’s estimated that 25 – 75% of seaweed’s dry weight is comprised of fiber. The sugars (sulfated polysaccharides) in seaweed have been shown to increase the growth of beneficial gut bacteria. Additionally, they can increase the production of short-chain fatty acids, which are needed to support and nourish the cells lining your gut.

  1. Apples

You know what they say about an apple a day. The pectin in apples accounts for approximately 50% of its total fiber content. Pectin increases butyrate, the short-chain fatty acid that promotes the health of the colon.

  1. Chicory Root

Chicory root has a wonderful coffee-like flavor. Roughly 47% of its fiber comes from the prebiotic inulin. Inulin nourishes gut bacteria and supports healthy digestion.

  1. Dandelion Greens

Dandelion greens are delicious in salads. High in fiber, they’re a rich source of inulin, which helps with elimination and boosts friendly bacteria in the gut.

  1. Jerusalem Artichoke

The Jerusalem artichoke’s fiber has a high inulin content making it even better than chicory root in boosting the colon’s friendly bacteria. It also helps to promote immune health.

  1. Garlic

Here’s another reason to love garlic…its fiber content contains both inulin and FOS. Garlic acts as a prebiotic by promoting the growth of bifidobacteria in the gut. As an added bonus, it stops unhealthy bacteria from growing.

  1. Onions

Onions are easy to work into the diet – you can add them to just about any dish. Similar to garlic, its fiber has inulin and FOS.

  1. Leeks

Super delicious in soups, leeks contain up to 16% inulin fiber, which makes your gut bacteria happy and helps with digestion.

  1. Asparagus

Asparagus is a delicious vegetable by itself or in a soup. It’s also another great source of prebiotics. The inulin content can be around 2-3 grams per 3.5-oz serving.

  1. Bananas

This popular fruit is rich in vitamins, minerals, and fiber. The fiber contains small amounts of inulin. Also, unripe bananas are high in resistant starch that has prebiotic effects.

  1. Barley

Barley is a wonderful cereal grain rich in beta-glucans. Beta-glucans are a prebiotic fiber that promotes the growth of friendly bacteria in the digestive tract. This fiber may help promote healthy blood sugar levels too.

  1. Oats

Oats are extremely versatile. You can enjoy them as a hot cereal in the morning or make oat flour and use them in baked goods. They contain high amounts of beta-glucan fiber and some resistant starch. Beta-glucans also support healthy cholesterol and blood sugar levels, which can slow digestion and help to control appetite.

Final Thought

To ensure your gut is healthy and happy, keep taking probiotics. Science shows they’re beneficial to your health. But they’ll be more effective if you feed them well with these prebiotic foods!

At BrainMD, we’re dedicated to providing the highest purity nutrients to improve your physical health and overall well-being. For more information about our full list of brain healthy supplements, please visit us at BrainMD.


Kim Henderson