Prebiotic Foods and Their Benefits

A collage showing an assortment of fresh vegetables, a bowl of yogurt with fruit, a person fermenting cabbage in a jar, and a close-up of microscopic bacteria.

What Are Prebiotic And Probiotic Foods?

Prebiotics and probiotics both play important roles in nurturing a healthy gut microbiome. Prebiotics are non-digestible food components that encourage the growth and activity of our beneficial gut bacteria in, while probiotics are live micro-organisms that confer health benefits to the host when consumed regularly in good amounts.

While probiotics directly introduce beneficial bacteria into our gut microbiome, prebiotics serve as nourishment for these beneficial organisms, promoting their growth and enhancing their beneficial effects even further.

Let’s talk further about both prebiotics and probiotics, but mainly prebiotics because probiotic foods and their actions are better covered on the post called Fermented Foods.

Hands placing shredded cabbage and carrots into a jar on a wooden cutting board, with additional shredded vegetables scattered around.

Prebiotics And Probiotics

Think of probiotics as being live organisms themselves, while prebiotics are their food, they are components of certain foods, different sugars and starches, that resist being broken-down, being digested in our gut, and it’s why we call them “resistant starches”.

SFCAs – This digestive-resistance allows prebiotic foods to reach our large intestine intact where they can ferment and stimulate the growth and activity of beneficial bacteria through the production of SFCAs (short-chained fatty acids). Studies shown that resistant starches help us address gut dysbiosis (SIBO). (Sobh et al., 2022)

Together, prebiotics and probiotics form a powerful symbiotic relationship that supports digestive health and overall well-being by maintaining a balanced and thriving gut microbiome. A study just published concludes with the ability of probiotics, prebiotics and postbiotics to alter the composition of human gut microbiota and the immune system hold great promise as a new medical frontier. (Zhou et al., 2024)

There are literally billions of microbes living inside our gut, with the highest concentration being inside our gut microbiome, our large and small intestines. Fermented foods rich in probiotic bacteria like yoghurt, sauerkraut, kefir, kimchi, and kombucha contain live micro-organisms known to help our digestive system get back into balance, even if we have a gut imbalance. (Valentino et al., 2024)

The term we use for poor gut bacterial levels, and an imbalanced microbial environment in the gut, is dysbiosis. Poor gut bacteria has been linked to SIBO, IBS, IBD, Candida overgrowth, as well as many common diseases like Type 2 diabetes, heart disease, and even different cancers. (Hills et al., 2019)

Therefore, maintaining a healthy gut microbiome contributes to overall health, and by consuming a diet rich in pre and probiotics you’ll be achieving that aim.

A selection of vegetables, including carrots, potatoes, onions, garlic, ginger, and celeriac, arranged on a burlap cloth.

Prebiotics

Prebiotics supports our body’s beneficial bacterial flora, they are different types of indigestible dietary fibre, specific components of plant-based foods that support the growth of beneficial bacteria in our gastrointestinal tract.

Prebiotics and probiotics are not the same thing, though, while almost all prebiotics tend to be made up of some kind of fibre, not all fibre will have a tendency to be prebiotic by nature. Prebiotic foods help to promote a healthier digestive system by enabling our gut bacteria to manufacture food to build the health of our colon’s cells.

Short-Chain Fatty Acids (SCFAs): Key Players in Gut Health

Short-chain fatty acids (SCFAs) are vital nutrients produced through the healthy fermentation of dietary fibers in the gut. Among the most important SCFAs are butyrate, acetate, and propionate.

These gut-derived fatty acids can significantly enhance overall health when absorbed into the bloodstream, contributing to benefits ranging from improved immune function to reduced inflammation (Jannsen 2016).

Prebiotics: Natural and Synthetic Sources

Prebiotics fuel the beneficial bacteria in your gut, but not all prebiotics are natural, nor are they created equal. Some prebiotics are derived from whole foods, while others are synthetic and added to processed foods or supplements.

Here are some prebiotic sources you might encounter:

Natural whole-food sources: Found in items like garlic, onions, asparagus, bananas, and artichokes.
Common synthetic prebiotics: Listed on labels as inulin, wheat dextrin, acacia gum, psyllium, polydextrose, galacto-oligosaccharides (GOS), or fructo-oligosaccharides (FOS).

Whole foods are generally the best source of prebiotics, as they provide a rich array of fibers and nutrients that work synergistically. However, your healthcare professional might recommend a prebiotic supplement, particularly if you struggle to consume enough prebiotic-rich foods. Supplements containing inulin or FOS can also be beneficial and are often included in dietary formulations for gut health.

Take-Away

Incorporating both SCFA-promoting fibre and prebiotic-rich foods into your diet can help optimise your gut microbiome, enhancing digestion, immunity, and overall wellness. Whether through whole foods or supplements, the key is finding a balance that supports your unique health needs.

Here are some of the benefits of prebiotics:

Prebiotics enhance digestion, boosting immune function, and assisting with nutritional absorption.
Prebiotic fibre can control our metabolism and weight by and make us feel fuller for longer.
Prebiotic fibre-rich foods are also excellent providers of vitamins, minerals, and other nutrients, all of which have a number of positive effects on health.

Prebiotic Supplement Caution

A woman in a light blue shirt sitting on a toilet, holding her stomach in pain with her head bowed.

While prebiotic supplements can support gut health, they may occasionally cause unwanted symptoms, particularly if the supplements are taken irregularly or in large doses. For example, inulin is known to sometimes trigger unwanted side effects, including gas, bloating, and loose stools.

This is one reason I often caution against relying on prebiotics in dietary supplements, like probiotics. In my clinical experience, these symptoms are not uncommon and can become a source of discomfort for those sensitive to certain types of prebiotics. It’s also why I stopped using prebiotics in my probiotic formulation years ago, preferring patients to consume foods containing prebiotic fibre instead.

If you decide to use prebiotic supplements, or probiotics containing them, consider the following:

Start Small: Introduce them in low doses to assess your tolerance.
Consistency Matters: Irregular use can make symptoms more unpredictable.
Monitor Symptoms: Keep track of any digestive changes and adjust your intake accordingly.

Remember, prebiotics are most effective and gentler on the gut when sourced from whole foods. However, if supplements are necessary, approach them mindfully and consult a healthcare professional if adverse symptoms persist.

Probiotics

A microscopic view showing blue rod-shaped bacteria floating in a bright blue environment.

Unlike prebiotics, probiotics are live bacteria that, when consumed, are essential for balancing and enhancing our gut microbiota. These beneficial micro-organisms, which include many Lactobacillus and Bifidobacteria strains, are well known for the many health advantages they bring us.

In order to keep our gut healthy, we need to make sure we are getting enough prebiotics, which is basically fibre that feeds our probiotic bacteria in our digestive systems, especially in the large intestine.

We need to include foods high in prebiotics (found in foods like onions and bananas, see the list below) and probiotics (found in foods like yogurt, sauerkraut and kimchi) in our diets.

While this page primarily focuses on prebiotics and their sources, you can find extensive information about probiotic-rich foods on the Fermented Foods page, including the very special foods like yogurt, kefir and sauerkraut.

Our Diet Needs To Be Balanced

Studies are showing that our diet affects our gut mycobiota, our internal fungal population, just as much as it is affecting our bacterial population. (Zhang 2021)

A detailed anatomical illustration of the human intestines, including the small and large intestines with visible blood vessels, akin to comparing ghee vs. butter in their intricate details.

Our mycobiome, the population of gut fungal species, plays a small but crucial role in regulating many vital functions in your gut, including balancing the bacterial and fungal population.

People who predominantly consume animal products in their diet, have been associated with having lower levels of Candida in their mycobiome than those with diets high in plant-based foods (people who mainly eat vegetables, fruits, legumes, beans, nuts, seeds, etc. (Hoffman 2013)

This does not mean we need to avoid FOS and GOS containing foods, because their benefits outweigh any negatives. These oligosaccharide-containing foods are a good fit alongside healthy proteins and fats in your diet, they do not need to be avoided because of Candida overgrowth. For example, studies have found oligosaccharides to bare good candidates for incorporation in a formula to prevent vaginal yeast infections (Rousseau et al., 2005).

They are an ally as you will soon learn, and can help build-up large intestinal colonies of Bifidobacteria, a beneficial bacteria shown to have powerful anti-fungal and probiotic anti-microbial abilities.

We need a balance between levels of healthy protein, fat and carbohydrates in our diet. Do we therefore need to be eating less vegetables, fruits, nuts, seeds, legumes, because we need to be eating more fats and animal protein? No, it doesn’t imply this at all, it means we need a healthy balance.

Prebiotic Food Caution

A person in a kitchen holding a notepad and marker while looking confused, surrounded by various vegetables, herbs, and olive oil bottles on the countertop.

Tip if you are new to a prebiotic or probiotic food:

When it comes to fermented foods, cultured foods, prebiotic foods or probiotic foods, especially if you have not previously tried this food – always start with a small amount (1/4 of a typical serving) and gradually increase quantities and the number of servings per day.

Here are a few tips:

Plenty Of Protein: Be sure to also include good levels of protein (animal or plant) in your diet.
Start Slowly: When consuming fermented foods, slowly increase your consumption of foods high in the oligosaccharides FOS and GOS. Tread carefully and slowly with any diet change, never be hasty.
Symptoms Teach Us: Gas, bloating, and lots of loose stools, let you know you need to back-off.

After some time, try to incorporate prebiotic foods into one or two snacks or meals daily. Once you feel many parameters of your health have picked up, and you’ve noticed you’re feeling better, it will usually be an indication that you’re building good levels of beneficial bacteria, your microbiome is getting more balanced.

But what are prebiotic foods, what are they made of, and more importantly, what benefits will we get to when it comes to our microbiome? Let’s talk about them now.

A tabletop filled with a variety of fresh vegetables, seeds, beans, and nuts. A wooden bowl contains carrots, asparagus, tomatoes, and more. A white plate has chickpeas, avocado, cabbage, and cucumbers.

What Are Oligosaccharides?

Many plant-based foods naturally contain prebiotic sugar chains that support gut health. These include legumes, whole grains, fruits, and vegetables. In addition to fresh produce, nuts, seeds, and legumes, some processed foods—like cereals, breads, and snacks—also contain prebiotic components.

Let’s explore two types of beneficial sugars commonly found in a healthy diet: oligosaccharides and polysaccharides.

Oligosaccharides are short-chain carbohydrates with three to ten sugar units. The term “oligos” comes from the Greek word meaning “few.”
Polysaccharides are long-chain carbohydrates with more than ten sugar units, derived from the Greek word “poly,” meaning “many.”

Oligosaccharides are unique because they cannot be digested by human enzymes. Instead, they travel undigested through the gastrointestinal tract until they reach the large intestine, where they encounter beneficial gut bacteria like Bifidobacteria and Lactobacillus. These bacteria possess the enzymes needed to break the bonds between the sugar units in oligosaccharides, fermenting them into energy. This process supports the growth of healthy gut flora.

However, excessive fermentation can lead to excessive gas, sometimes causing discomfort or bloating. Many of us have encountered someone with this issue—often linked to an imbalance in their diet. Balancing prebiotic-rich foods is key to reaping their benefits without unwanted side effects.

An elderly woman with short gray hair holds her back in pain while sitting on a couch, wearing a light blue t-shirt in a well-lit room.

**Caution If You Have A Sensitive Gut**

Patients with conditions like Candida overgrowth, SIBO, irritable bowel syndrome and inflammatory bowel conditions, (IBD) often experience a “touchy” or sensitive gut. This is frequently linked to insufficient levels of beneficial bacteria. Without enough good bacteria to balance gut flora, these individuals are more prone to excessive fermentation, leading to gas, bloating, abdominal pain, and irregular bowel movements such as constipation or diarrhea. Inappropriately high fermentation of oligosaccharides due to a lack of bacteria to “digest” them exacerbates these symptoms.

Recent research shows that nearly 1 in 7 Americans regularly experience bloating, yet most do not seek professional help (Oh 2022). In my experience, dysbiosis—an imbalance in gut bacteria—is a common underlying cause of these issues.

If you are a highly sensitive person (HSP), you may also be more reactive to certain foods and drinks. Studies indicate that highly sensitive individuals are more likely to experience symptoms like reflux, abdominal pain, indigestion, diarrhea, or constipation (Limura 2022). For HSPs, introducing fermented foods into the diet requires extra caution to avoid triggering symptoms.

In contrast, individuals with a balanced microbiome and robust populations of beneficial bacteria typically have smooth digestion. They experience minimal gas, no bloating, and regular, comfortable bowel movements. Unfortunately, this is not the case for those with Candida, SIBO, IBS, or IBD. How would you describe your daily digestive and elimination process?

Let’s now talk about the two prebiotic sugars when it comes to your diet:

Main Oligosaccharides are FOS and GOS

FOS and GOS are different kinds of beneficial sugars you’ll soon learn about, because not all carbohydrate foods are strictly forbidden in your Candida diet, some can in fact be beneficial according to studies as we’ll see.

FOS Fructo-oligosaccharides

FOS are short-chain carbohydrates classified as oligosaccharides, naturally present in various plants. They are especially abundant in Jerusalem artichokes, blue agave, yacon roots, leeks, garlic, onions, bananas, Chinese radish, chicory, and asparagus. Scallions and white onions contain moderate amounts, while Jerusalem artichokes, chicory root, and garlic have the highest levels, earning the Jerusalem artichoke its nickname, “fartichoke” (Malinovska 2011).

Benefits and Stability

FOS is a stable, soluble fiber that withstands high temperatures and varying pH levels, making it ideal for processed foods like infant formula, yogurt, and baby food. Because humans cannot digest FOS, it does not affect blood sugar levels. Instead, it travels undigested to the large intestine, where it promotes the production of short-chain fatty acids (SCFAs).

Gut Health Impact

FOS cause bacterial fermentation in the colon as they pass into the large intestine undigested. A meta-analysis confirmed that FOS intake strongly correlates with increased levels of Bifidobacteria. Higher doses and longer intake further amplified these benefits (Dou 2022).

Recent research found FOS to be “bifidogenic,” promoting the growth of Bifidobacteria and Lactobacillus bacteria. Its anti-inflammatory properties make it an excellent choice for managing gut-related conditions (Mahalak 2023).

FOS and Candida

If you have Candida overgrowth, avoiding all oligosaccharide-containing foods may not be necessary. FOS can enhance gut health by stimulating Bifidobacteria and lactobacillus growth, which can inhibit Candida albicans.

Research has shown that Bifidobacteria reduce intestinal pH levels, hindering fungal growth. Probiotics and resistant starch-rich diets further encourage Bifidobacteria colonization, further improving gut resistance to Candida.

Studies have found that FOS alone could reduce the environmental pH, significantly inhibit the growth of the harmful bacteria Escherichia-Shigella and Bacteroides, while significantly promoting the growth of the beneficial bacteria Bifidobacterium and Lactobacillus (Fu et al., 2023).

In summary, FOS-rich foods are valuable for supporting beneficial gut bacteria, reducing inflammation, and aiding in Candida control, thanks to their role in promoting SCFA production, lowering gut pH, and boosting beneficial bacteria counts.

Foods Highest in FOS (Fructo-Oligosaccharides)

Fructo-oligosaccharides (FOS) are a type of prebiotic fibre that supports the growth of beneficial gut bacteria, particularly Bifidobacteria. Naturally found in a variety of fruits, vegetables, and grains, FOS is often associated with improved digestion and enhanced gut health. The highest concentration of FOS has been found in yacon root (Caetano et al., 2016).

Incorporating FOS-rich foods into your diet can help maintain a balanced microbiome while offering a range of nutrients. Below is a list of foods particularly high in FOS:

Artichokes (Globe): A top source of FOS, artichokes are excellent roasted, steamed, or added to salads.
Asparagus: This versatile vegetable is packed with FOS and works well in stir-fries, soups, or as a side dish.
Bananas (Slightly Green): A convenient snack high in FOS, especially when they are slightly underripe.
Chicory Root: One of the richest natural sources of FOS, often used in supplements or as a coffee substitute.
Garlic: A culinary staple, garlic is rich in FOS and enhances both flavor and gut health.
Jerusalem Artichokes (Sunchokes): These tubers are exceptionally high in FOS and can be roasted or pureed for a creamy dish.
Leeks: Particularly the white bulb, leeks are a mild-flavored source of FOS and are great in soups or sautés.
Onions: A common kitchen ingredient with high FOS content, onions can be eaten raw or cooked.
Rye: Found in bread, crackers, and other baked goods, rye contains a notable amount of FOS.
Wheat Bran: A fiber-rich component of whole wheat that provides FOS and supports digestion.
Yacon Root: Contains the world’s highest known FOS concentration. of any food.

Including these foods in your diet regularly can help boost FOS intake, promoting a healthy gut microbiome and improving overall digestive health.

Actions Associated With FOS Intake

Anti-Inflammatory:
FOS’s bifidogenic properties contribute to the reduction of intestinal inflammation, which is beneficial for inflammatory gut-related conditions (Van Langen et al., 2009).
Anti-Microbial:
It’s anti-microbial – Other studies have shown GOS can influence the immune system through the production of anti-microbial substances, reducing pathogenic bacteria. (MacFarlane 2008)
Beneficial Bacteria Growth:
FOS is bifidogenic, meaning it specifically stimulates the growth of Bifidobacteria, but also Lactobacillus species, both of which are essential for maintaining a healthy gut microbiome (Mahalak et al., 2023).
Constipation:
FOS contributes to a healthy digestive process by encouraging consistent bowel movements and alleviating issues like constipation through improved gut motility (Meksawan, et al., 2016), (Bellini et al., 2021), (Wegh et al., 2024).
Candida :
Research has shown that Bifidobacteria reduce intestinal pH levels, hindering Candida growth (Sharma 2021), (Ricci et al., 2022).
Gut Microbial Balance:
FOS helps correct dysbiosis by encouraging the proliferation of beneficial bacteria and inhibiting harmful microbes, thereby restoring a balanced microbiome. (Gagliardi et al., 2018).
Intestinal Barrier:
By supporting SCFA production, FOS enhances intestinal barrier function, reducing “leaky gut” issues and preventing toxins or pathogens from entering the bloodstream (Ney et al., 2023).
SFCA Production:
Once fermented by beneficial gut bacteria, FOS generates Short-Chained Fatty Acids (SCFAs) such as butyrate, acetate, and propionate. These compounds improve gut health by nourishing intestinal cells, lowering inflammation, and maintaining gut barrier integrity (Fusco et al., 2023).

Assortment of various nuts in small round bowls arranged in a grid pattern.

GOS Galacto-oligosaccharides

GOS is sometimes used as a functional food for young children, and is used in various food products. is thought to have a laxative effect because of how it functions as a soluble fibre. (Axelrod el at., 2018)

Like FOS, oligosaccharides cause bacterial fermentation in the colon as they pass into the large intestine undigested. The primary dietary sources of GOS are legumes (e.g., beans and lentils), seeds, and nuts, making them a valuable addition to a balanced, fibre-rich diet.

Many studies with infants and adults have shown that foods or drinks enriched with galacto-oligosaccharides result in a significant increase in Bifidobacteria. (Jeurink 2013)

Foods Highest in GOS (Galacto-Oligosaccharides)

Galacto-oligosaccharides (GOS) are prebiotic fibre that nourish beneficial bacteria and are found in a variety of plant-based foods. Here’s an expanded alphabetical list of GOS-rich foods to incorporate into your diet:

Beetroot: Fresh or cooked beetroot is an excellent source of GOS and can be added to salads, soups, or roasted dishes.
Butternut Pumpkin: Also known as butternut squash, this versatile vegetable is high in GOS and perfect for roasting, soups, or mashes.
Cashews: These creamy nuts are not only rich in healthy fats but also a great source of GOS.
Chickpeas: Found in whole form or as the base for hummus, chickpeas are a fantastic way to boost your GOS intake.
Custard Apple: A tropical fruit rich in fiber and prebiotics, including GOS, with a sweet and creamy texture.
Freekeh: A young, roasted green wheat that contains GOS and works well in salads, pilafs, or as a rice substitute.
Hummus Dip: Made from chickpeas and tahini, this creamy dip is a convenient and tasty source of GOS.
Kidney Beans (Red): These legumes are packed with GOS and can be used in stews, salads, or chili dishes.
Oat Milk: This popular plant-based milk alternative often contains GOS, making it a gut-friendly choice for beverages or baking.
Pistachios: A nutrient-dense nut that provides GOS along with protein and healthy fats.
Soy Milk (from Whole Soy Beans): Rich in GOS, soy milk is a versatile base for smoothies, cereals, or coffee.
Soy Milk Drinks (e.g., Soy Cappuccino): Beverages made with GOS-rich soy milk offer a convenient way to support gut health.
Split Peas: High in GOS and perfect for soups, stews, or purées.
Thawed Green Peas: While fresh peas are lower in GOS, frozen and thawed peas retain higher levels and can be added to a variety of dishes.

Including these foods in your diet regularly can help promote a healthy gut microbiome while adding a variety of flavors and textures to your meals.

Actions Associated With GOS Intake

Anti-Allergic:
GOS has been shown to reduce allergic responses by modulating the immune system, potentially lowering the risk of food allergies, asthma, and eczema, especially in children (López-Enríquez et al., 2023).
Anti-Microbial:
It’s anti-microbial – Other studies have shown GOS can influence the immune system through the production of anti-microbial substances, reducing pathogenic bacteria. (MacFarlane 2008)
Antiviral Effects:
Preliminary studies suggest GOS may play a role in inhibiting viral infections by enhancing gut immunity, though more research is needed to confirm these effects (Markowiac et al., 2017).
Constipation :
GOS is good for constipation – oligosaccharide fermentation by bacteria boosts bacterial mass, which in turn boosts faecal bulk. (Niittynen 2007).
Diabetes:
GOS has been linked to better blood sugar control by influencing gut hormones like GLP-1, which regulate appetite and glucose metabolism. This suggests benefits for managing Type 2 diabetes (Zhu et al., 2019).
Gut Barrier Function:
By enhancing the growth of beneficial bacteria, GOS strengthens the intestinal barrier, reducing intestinal permeability or “leaky gut.” This protects the body from the entry of harmful pathogens and toxins (Hu et al., 2024).
Gut Immune Health:
GOS modulates the immune system by promoting the production of antimicrobial peptides and substances. This helps combat pathogenic bacteria and viruses while reducing the risk of infections. (MacFarlane et al., 2008)
Irritable Bowel Syndrome:
GOS has been shown to reduce symptoms of IBS, including pain, bloating, and constipation. This makes it a valuable dietary intervention for individuals with sensitive or disrupted gut function (Silk 2009).
Laxative Properties:
As a soluble fiber, GOS can function as a mild laxative, promoting regularity through its fermentation process in the colon. (Guan et al., 2021)
Mental Health:
Emerging research suggests that GOS may influence the gut-brain axis by promoting the growth of bacteria that produce neurotransmitters like serotonin. This may help alleviate anxiety and depression. (Chen et al., 2021).
Prebiotic:
GOS is a prebiotic that stimulates the growth of beneficial bacteria, particularly Bifidobacteria, in both infants and adults. Increased Bifidobacteria supports gut health, improves digestion, and helps maintain a balanced microbiota. (Davani-Davari et al., 2019)
Probiotics:
GOS works well when combined with probiotic supplements, as it provides a food source that supports the growth and colonisation of beneficial microbes (You et al., 2022).

Take-Away

GOS is a powerful prebiotic with a broad range of benefits, from improving gut health and immune function to enhancing mineral absorption, reducing inflammation, and supporting metabolic and mental health. It is a versatile functional ingredient suitable for people of all ages, including infants, those with IBS, and individuals managing chronic conditions like diabetes or allergies.

A basket of assorted fresh fruit including apples, pears, and plums on a wooden table with leaves and nuts scattered around.

Best Prebiotic Foods

The following examples highlight some foods naturally rich in prebiotics, along with various ways to enjoy them in your diet.

While this is not an exhaustive list, it offers a glimpse into the many sources of galactooligosaccharides (GOS), fructooligosaccharides (FOS), and inulin-containing foods that can support gut health.

The following foods are rich in beneficial sugars, starches, and fibre that nourish and promote the growth of beneficial bacterial colonies in our gut.

By regularly incorporating them into your meals, you can encourage a thriving microbial environment that supports not only digestion but also overall health and well-being. But as we shall soon see, by incorporating prebiotic and probiotic foods we get an even better outcome.

As these foods stimulate the growth of beneficial bacteria such as Lactobacillus and Bifidobacteria, they enhance the gut’s natural defences. A robust population of these helpful microbes creates a resilient barrier against potentially harmful pathogens, including Candida albicans, safeguarding your digestive system from imbalance and infection (Ricci et al., 2022).

Prebiotic Foods List

Allium vegetables – Garlic, leeks, onions, chives, shallots, red onions, spring onions.
Drinks – kombucha, chamomile tea, black tea, green tea.
Fruit – Bananas, persimmon, pomegranate.
Grains and cereals – Sourdough bread, oats, amaranth.
Legumes: adzuki beans, chickpeas, pinto beans, navy beans, soybeans, black-eyed peas, kidney beans, Lima beans, green peas, lentils (all).
Many vegetables – cauliflower, broccoli, Brussels sprouts, kale, kohlrabi, Bok choy, Asparagus, butternut squash, globe artichoke, beetroot, green beans.
Nuts and seeds – Sesame seed, sunflower seed, pumpkin seeds, chestnuts, hazel nuts, pecan nuts, macadamia nuts, pistachios, cashews.
Root vegetables: Jerusalem artichokes, burdock roots, chicory, yacon roots, dandelion roots.

Prebiotic Food Hints and Tips

To summarise, you don’t have to completely avoid oligosaccharides if you have Candida, IBS, or IBD and are wanting to reduce your symptoms. These foods may prove to be quite useful. You’ll find it easy to incorporate prebiotic-rich foods into many meals to encourage the growth and proliferation of good gut bacteria with a little more effort and preparation. Just remember to take it easy at first at least.

These foods serve as prebiotics and promote the development of our beneficial micro-organisms. Additionally, they contain a lot of minerals and fibre, so include some in your Candida diet. Here are a few pointers:

For Sensitive Gut: avoid foods containing the highest amounts of GOS and FOS (see examples above).
Small Amounts Of Nuts: , (they are highly concentrated foods) for example, eat no more than 8 or 9 almonds or 3 Brazil nuts with any snack or meal. Chew them really well until they are like a paste in your mouth.
Add Seeds To Meals: Add pumpkin, sunflower, and sesame seeds to meals. Add ground seeds to your porridge, smoothies, and baked foods. Not too much, common sense.
Canned Chickpeas: For convenience, use canned chickpeas or lentils. My preference is to use dried chickpeas and soak overnight before cooking.
Gluten-Free: If you want to go gluten-free, it’s an option, not mandatory. Some people may wish to opt for gluten-free grains like quinoa, sorghum, millet, amaranth, brown rice, and corn.
Lemons and Limes: If you are nervous about fruits, read the fruit section on this website. Start small, berries, avocado, different citrus fruits like lemon and lime and always allowed.
Hummus and Vegetables: Carrots, bell peppers, celery, and cucumber, all make a good snack when consumed with hummus.

FOS, GOS, and Fermented (Probiotic) Foods: A Perfect Match

Research from Stanford School of Medicine highlights the transformative impact of fermented foods on gut health. A diet rich in these foods not only enhances microbial diversity but also lowers key markers of inflammation, making them an excellent addition to your routine (Weaver 2021).

For those managing conditions like Candida, SIBO, IBS, IBD, or other gut imbalances:

High-Fibre Foods may be difficult to tolerate initially, depending on the current state of your gut microbiome. Higher levels of beneficial bacteria make it easier to tolerate high-fibre foods.
Small Portions of Fermented Foods can be a gentler way to increase gut microbial diversity without relying heavily on fibre. One tablespoon may even be a suitable portion-size for some to begin with.
Experimenting with foods regularly helps you discover what works best for your body as it heals.

How Diet Shapes Our Gut Microbiome and Immune System

The choice of foods in our diet plays a crucial role in shaping our gut microbiome, which, in turn, significantly influences our immune system. A recent clinical trial involving 39 healthy adults explored this connection by comparing the effects of two distinct dietary approaches over a 10-week period (Wastyk et al., 2021).

The study aimed to evaluate how two microbiota-targeted dietary interventions—one emphasising plant-based fibre and the other focusing on fermented foods—impact the composition and function of our human microbiome and its interaction with the immune system.

The findings offer valuable insights into how specific dietary choices can promote gut and overall health:

High-fermented food diet: Included yogurt, kefir, fermented cottage cheese, kimchi, fermented vegetables, brine-based drinks, and kombucha.
Resulted in a steady increase in microbial diversity.
Markedly reduced inflammatory markers.
Benefits were seen with both large and small portions, meaning even a little bit, eaten regularly, can make a difference (e.g., a spoonful of sauerkraut or a small serving of yogurt).
High-fibre diet without fermented foods:
Did not increase microbial diversity.
Suggests fibre alone may be insufficient for boosting microbiota diversity without the inclusion of fermented foods.

Take-Away

Incorporate both fermentable fibre foods (like FOS and GOS) and fermented foods for a synergistic effect.
Start small, especially if your gut is sensitive, and build gradually.
Regular, modest portions of fermented foods can provide measurable benefits for gut health and inflammation (Wastyk 2022).

This combination offers a simple yet powerful strategy to support a healthy, balanced gut microbiome.

The Role of Prebiotics in Supporting Vaginal Health

Prebiotics are non-digestible food components that nourish and stimulate the growth of beneficial bacteria, particularly in the gastrointestinal tract. These compounds play a crucial role in fostering a healthy microbiome, which can help reduce the risk of bacterial vaginosis (BV), vaginal yeast infection, and other vaginal or genital infections.

A diet rich in plant-based foods is naturally abundant in fibre, which serves as an excellent source of prebiotics. Incorporating these foods into your daily meals can support both gut and vaginal health.

Do Fermented Foods Aggravate Your Symptoms?

A woman in a light pink T-shirt stands in a kitchen, holding her stomach with both hands, appearing to be in pain.

As with any food or drink, consuming fermented foods in excess or too frequently can sometimes cause discomfort, especially if your gut is sensitive or already compromised. Moderation and mindfulness are key when introducing these powerful foods into your diet.

Consider common fermented foods like yogurt, sauerkraut, and kefir, and how they might impact your gut:

Potential Reactions:
Some people may experience increased gas, bloating, or mild cramping after consuming fermented foods. This is more likely if you have pre-existing gastrointestinal issues such as IBS, SIBO, or Candida overgrowth.
Individual Tolerance:
Everyone’s gut is different, and there may be a threshold for how much or how often your digestive system can handle these foods.

In my clinical practice, I often explore whether specific foods, beverages, or snacks might be triggering symptoms. Identifying patterns and testing tolerances is crucial for finding a balance that works for you.

If you notice aggravations, consider:

Reducing portion sizes: Start with small amounts, like a teaspoon of sauerkraut or a few sips of kefir, and gradually increase.
Spacing out consumption: Instead of daily, try every other day to allow your gut time to adjust.
Monitoring your symptoms: Keep a food diary to track any changes and pinpoint triggers.

Fermented foods can offer incredible benefits for gut health, but listening to your body and adjusting as needed is essential to reap those benefits without discomfort.

Eric Bakker with glasses, wearing a blue t-shirt, sitting in a room with bookshelves. He is discussing why we don't need weight loss pills

Questions I Would Ask Patients:

Here are a few typical questions I would ask a patient coming to see me, especially if they ticked the fermented foods box on the patient intake form.

Otherwise, I would always ask in detail anyway what foods they would consume for breakfast, lunch, and supper, including snacks and drinks.

What kind of fermented foods would you normally consume?
How long have you consumed this food/drink for?
Do you consume it with other foods or drinks?
Tell me how much you were consuming on a regular basis
What does your gut feel like after eating it?
Did this food cause an exacerbation of symptoms, if so, tell me about it.
Is your bowel function affected by fermented foods? If so, how?

How would you answer these questions? Have a think, and whether the fermented foods category is good for you now. Should you perhaps wait until your gut improves? Are you OK with small portions? How is your gut and stool the next day, were they affected by these foods?

It’s always good to reduce your intake of fermented foods until you are confident in your gut health, and to keep your consumption down to one type or category until you feel better in your gut, a lot better.

The Best Foods To Feed Our Microbiome

Probiotics are live beneficial bacteria that can directly influence your microbiome. Foods like yogurt, kefir, sauerkraut, kimchi, kombucha, and other fermented foods contain probiotics. Including these regularly in your diet can help maintain a healthy gut microbiome. Check-out the following key articles:

Key Articles

Eating more foods that are high in probiotics is good for you in many ways and can improve your health and well-being as a whole.

Here are some important reasons to eat foods high in prebiotics and high in probiotics:

Probiotic-Rich Foods Support Gut Health: Probiotics are live, good bacteria that live in your gut and help keep it healthy. They help keep the gut microbiome healthy and balanced, which is important for digestion and nutrient intake.
Probiotic-Rich Foods Help Balance The Microbiome: A wide and balanced gut microbiome is linked to better health in general. Probiotics help keep this balance by raising the number of good bacteria and decreasing the number of bad bacteria.
Improved Digestive Health: Probiotics help your digestive system break down and absorb food. They can help with stomach problems like gas, bloating, and diarrhoea.
Boosts Immune Function: Your gut is home to a big part of your immune system. Probiotics can boost your immune system, which means they can help your body fight off infections and sicknesses.
Reduces Inflammatory Response: When the gut bacteria is out of balance, it can cause chronic inflammation, which is linked to many health problems. Probiotics can help lower inflammation and make the immune system work better.
Enhanced Nutrient Absorption: A good gut microbiome can help your body absorb vitamins, minerals, and other important nutrients from the food you eat.
Supports Our Mental Health: There is growing proof of a link between the gut and the brain, which is sometimes called the “gut-brain axis.” By changing how neurotransmitters are made, probiotics may be good for your mental health and happiness.
Help Manage Our Weight: According to some studies, having balanced gut bacteria may help you control your weight by keeping your metabolism healthy and cutting down on your cravings for unhealthy foods.
Reduced Allergy Risk: It lowers the chance of getting allergies. By changing the immune response and increasing immune tolerance, probiotics may help lower the chance of getting allergies, especially in kids.
Improved Skin Tone: The health of your gut can affect the health of your skin. If you have acne, eczema, or psoriasis, probiotics might help make your face better.
Supports Oral Health: Eating and taking foods and probiotics that are high in probiotics can help your oral health by reducing the risk of gingivitis and help stop the growth of bad bacteria in your mouth.
Improves Women’s Health: For women, probiotic-rich foods can help keep the vaginal microbiome healthy, which lowers the risk of Candida yeast infections and improves general urogenital health.
Reduce Risk Of Chronic Diseases: some studies show that probiotics may help people with long-term conditions like diabetes, irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD) figure out how to take care of their health.
Recovery After Antibiotics: Antibiotics change the gut bacteria. After taking antibiotics, eating probiotic rich foods can help reset the balance of good bacteria in the body.

There are many health benefits to eating foods that are high in probiotics, and unlike the 1980s, we can easily add probiotic-rich foods to your diet today they are easy to find and get at your local store.

Yoghurt, kefir, cabbage, kimchi, kombucha, and some of the older cheeses are all examples. You can read everything you need to know about these probiotic-rich fermented foods on the respective links.

Eric Bakker N.D.

Greetings! I am a naturopathic physician from New Zealand. Although I’ve retired from clinical practice since 2019, I remain passionate about helping people improve their lives. You’ll find I’m active online with a focus on natural health and wellbeing education through my Facebook page and YouTube channel, including this website.