If you’re familiar with probiotics, good bacteria and microbiome, then you probably know a thing or two about gut health. While getting plenty of good bacteria in the gut is great for our health, it is equally important to keep that bacteria fed and happy. That’s when prebiotics come into play! In today’s place, we look at the best sources of healthy prebiotic foods.
So, what exactly is a prebiotic?
If you’re familiar with insoluble and soluble fibre, you likely understand a vital characteristic of prebiotic foods already: a prebiotic is a food ingredient that cannot be digested. Foods with lots of insoluble fibre (which doesn’t get digested) are often good sources of prebiotics.
Like fibre, prebiotics can help smooth things out in the digestive tract and keep you feeling regular. Moreover, they promote the growth of microorganisms in the intestines like good bacteria which is part of why they work together with probiotics.
Once they pass through the small intestine without being digested, the prebiotic foods are then fermented in the large intestine by preexisting bacteria. Here, it becomes the perfect source of nutrition for the bacteria in the gut, giving it the fuel it needs for optimal health.
This is why prebiotics must be taken in conjunction with probiotics whether in supplement form or if you get yours in mostly with fermented foods.
What is the difference between a probiotic and a prebiotic?
Probiotics produce beneficial bacteria – think yoghurt, kefir, sauerkraut, kombucha or a supplement. Prebiotics then provide nutrition or food for that beneficial bacteria. Prebiotics can be found as supplements but it’s best to get them from food sources (outlined below).
The benefits of prebiotics
Now that you know prebiotics and their relationship to probiotics you can deduce that this is one powerful combination for promoting healthy gut flora, intestinal integrity, and the ability for your gut to keep the bad guys out. Delving a little deeper, let’s see what benefits taking prebiotics for gut health can provide for you down the road.
Digestion isn’t everything, but it is a great indicator of overall health. If things are moving smoothly, you can generally gauge what foods work best for you and which foods don’t. Other things are likely going to fall into place too.
The gut flora and the diversity of the (good) bacteria that resides in our gut can really explain so much else about our health. We can trace just about everything back to the gut. Probiotics are made to deliver gut bacteria while improving the lining, making it less vulnerable to invasions of bad bacteria.
The bacteria need prebiotics as fuel. They begin to chow down on these non-digestible fibres and they’re then able to produce short-chain fatty acids. In addition to butyric acid (a favourite healthful benefit of butter), this brings balance and regulation to electrolyte levels while increasing the strength of the intestinal lining.
Boost your immune system
If our immune system is compromised, we can likely trace back why exactly that is to the gut. Without a solid colony of bacteria in the gut, we face some issues. The epithelial tissue that protects the gut is dependent on that good bacteria, so when it’s not present, pathogenic bacteria are more likely to increase.
Ideally, that tissue regenerates on its own with the fuel it needs. Considering prebiotic foods have the potential to change our flora and what it’s comprised of, it’s linked to an improving immune system.
The prebiotic effect is overall associated with reducing cancer-causing enzymes and the body’s ability to absorb minerals and vitamins. While we can take plenty of supplements, it’s not doing us any favours if our body can’t do much with them. Better gut health = better bioavailability and prebiotics are the first step to that.
Better hormonal health
Hormones are a delicate balance for many, especially those who live stressful lives (all of us sometimes!). Hormones get whacky when the stress sets in and while many of us can recover, chronic stress is wreaking havoc on your chemical balances.
Poor gut health can continually weaken the stress response, and this is why we can draw some conclusions about a real food diet (including prebiotic foods) and the positive effect on stress and stress-related disorders.
Some research has shown that over time, prebiotic consumption makes individuals less reactive to stress and shifts focus to positive thoughts rather than negative thoughts. This can be explained by decreased attention vigilance. Essentially, it acts as an adaptogenic compound making us more resilient, decreasing and regulating cortisol release which controls our “fight or flight” response.
Considering the bioavailability of many vitamins and minerals are increased with prebiotic consumption, our bones can benefit from that extra dose of calcium, iron, and magnesium. A nutrient-dense diet is only as good as your gut is!
Prebiotics can help prevent osteoporosis, increase bone density and keep your skeleton strong, warding against breaks, fractures and sprains. On the same note, prebiotic consumption can help you to address other vitamin and mineral deficiencies.
Promote weight loss
There are a few magical components of successful weight loss, and good gut health is going to make it easier to get those things in place. For example, prebiotic intake and good gut health have been associated with increased satiety, regular blood sugar levels, and energy stability.
Not only does fibre promote healthy and regular digestion, but it fills you up by expanding in the stomach. This applies to the indigestible fibrous material too as it kind of “hangs out” for a bit while the rest passes through slowly. If you’re feeling full, you’re less likely to overindulge between meals or during meals.
Bonus: since prebiotics keep our hormones happy and stress levels down, they’re less likely to become the cause of our cravings which can sabotage weight loss goals. Imbalanced hormonal glands including the adrenals, pituitaries and thyroid gland are some of the most common reasons for weight gain or weight loss resistance
The best prebiotic foods
If you eat a wide variety of nutrient-dense whole foods or a veggie-heavy diet, you’re likely getting in quite a lot of prebiotic foods already. Resistant starch, inulin, and non-digestible carbohydrates come from almost all fruits and vegetables. Some contain more prebiotic power than others, so I’ll share my top 20 prebiotic foods with you, including a few overlooked sources.
For the most part, you can look for prebiotics in cruciferous veggies like kale, broccoli, and cabbage, roots, and whole grains (if you’re not eating strict paleo). Many of these foods should be consumed raw or lightly cooked, and none should be used in excess.
Caution: Prebiotic foods can cause bloating and gas, so try to consume them in smaller amounts. It’s worth noting many folks can eat plenty of cruciferous veggies cooked, but end up with digestive distress when eating raw.
Asparagus contains 2-3 grams of inulin per 100 grams, promoting healthy gut bacteria growth. It’s more potent raw, so try shaving some thin over a salad or stir-fried with some garlic and lemon juice.
My Chicken & Chorizo with Asparagus is an easy, one-pot dish that’s sure to satisfy – very little effort required!
About 10% of the fibre found in onions is made of inulin with compounds that also help to break down fats and keep that gut flora going strong. Raw onions are more potent. Try my marinated red onions, which you can put on pretty much everything.
Leeks are similar to onions, so unsurprisingly, they have similar health benefits. Leeks contain up to 16% inulin fibre, higher than even onions! Raw leeks or roasted leeks are great additions to salad and any other dish to boost onion/garlic flavour profile.
Garlic is one of the healthiest foods on the planet, known for being an awesome immune booster while adding deep flavour to meals. Make an excuse to get a little more in! A blend of fructooligosaccharides and inulin make its prebiotic power high.
Try my Sweet Potatoes with Walnut, Parsley & Garlic for a flavourful and fibre-rich side dish.
5. Dandelion root
Whether you prefer to blend dandelion greens in pesto or you brew the root, dandelion root is a great source of inulin fibre. This green is a major superfood with tons of other benefits too, and a versatile range of uses. I even like to munch on it raw, and you can easily grow some in your garden.
Who doesn’t love a good excuse to snack on an apple? An apple a day keeps the doctor away, after all. The pectin – which accounts for 50% of apple’s fibre content – packs in the prebiotic punch, increasing butyric acid to feed that good gut bacteria.
7. Jerusalem artichoke
Jerusalem artichokes are also called sunchokes. They’re an underrated veggie in my book, mainly because 76% of its fibre content comes from inulin making it one of the most prebiotic-rich foods.
Jicama is a crunchy, watery, fibrous veggie similar to apple but a little less sweet. It’s great served raw and sliced up to dip in your favourite blends. It’s a very low-calorie source of inulin fibre. You can also slice and roast them into “fries,” or use in salsas and salads.
9. Chicory root
By now, it’s probably obvious that many roots contain lots of prebiotic potentials. Chicory is no exception. It’s a fabulous coffee substitution if you’re trying to ditch caffeine. Try a herbal coffee blend rich with chicory for a fantastic source of inulin.
My favourite way to consume chicory is to brew the root in hot water like in Teeccino “coffee” blends.
Specifically, green bananas. Yes – the unripe bananas! No, they’re not the sweetest snack ever but they are a great source of prebiotics or resistant starch. This fibre can increase healthy gut bacteria and reduce bloating.
You can eat unripe bananas plain for a fibre boost, but it’s easier to get this source from green banana flour – a grain-free wheat flour alternative that is very versatile with amazing benefits.
11. Konjac root
Unsurprisingly, there’s another root that comes in on the list today. Konjac root or elephant yam contains glucomannan fibre making it pretty unique, with many benefits for the gut and the bacteria in it. This is often found in shirataki noodles – a low-carb, low-calorie pasta alternative made from the yam fibre.
Try my Shirataki Noodle Salad with Lime & Sesame Dressing. They are delicious in cold noodle salads, and 100% grain-free!
12. Cocoa POWDER
It delights me to add a little chocolate to this list. Raw cacao or cocoa powder is an antioxidant-rich, prebiotic-packed addition to your smoothies, yoghurt, or healthy baked goods.
Try a batch of these Paleo Chocolate Brownies to get your fix.
Flaxseed is another easy supplemental food to boost prebiotic fibre and promote healthy gut flora. You can use ground flaxseed as a binding agent or in baking and sprinkle seeds on smoothie bowls or paleo porridge.
Seaweed is not only a great source of iodine which is tough to get in the diet, but it’s also a great source of prebiotic fibre. 50-80% of the fibre in seaweed is water-soluble, and consumption may inhibit the growth of disease-causing bacteria while promoting the growth of the good stuff.
We have yet another root! All types of radishes are fibrous and good for the gut. Try toasting them or slicing them raw into salads for an easy boost when you need it.
I love to make salsa with radishes. Check out my Radish & Egg Salad or get your fibre in at breakfast with my Mexican Scrambled Eggs and Avocado with Radish Salad.
16. Coconut & coconut flour
Coconut meal and coconut flour contain tons of prebiotic potential with so many uses. Coconut shreds can be used in desserts or smoothies, and coconut flour makes a fabulous, dense wheat flour replacement.
17. Sweet potatoes
Sweet potatoes are a fantastic source of starch. To improve the percentage of resistant starch, cook your sweet potatoes in coconut oil first then eat them after they’ve cooled in the fridge.
I love serving them up roasted with garlic for double the gut-friendly benefits. I also like to use them as a noodle replacement, like in this Beef Ragu with Sweet Potato Pasta. More healthy sweet potato recipes here.
18. Hemp seeds
I like to emphasise the prebiotic content in tiny superfoods like flaxseed and hemp seed because they are insanely easy to add to the diet. Hemp seeds are high in protein and make a great whey replacement for protein powder on a paleo diet. The seeds are nutty, and work well in homemade paleo energy balls. Try these hemp seed cookies as well.
This humble green is a not-so-secret favourite of mine. I love using it for raw slaw salads, in a saute or a stir-fry, or to add bulk to soups. Cabbage is a surefire way to get in a lot of fibre, and there are so many delicious varieties to choose from.
A handful of berries packs in a fibrous punch for a colourful and nutritious snack. I like making berry smoothies, adding them to coconut yoghurt, or just dipping them into some coconut whipped cream.
Since raw berries are a better source of prebiotic fibre, I can’t recommend my Paleo Chocolate Cake enough… the topping couldn’t be simpler!
PREBIOTICS IN BEANS & LENTILS (LEGUMES)
The above food sources of prebiotics are all based on non-grain and non-legumes foods. I have to mention that another fantastic source is beans and lentils, basically most legumes. Many people find pulses and legumes difficult to digest and some avoid these foods due to their diet, hence they are not included in my Top 20 list. However, if you can tolerate and digest legumes, they provide plenty of prebiotic fibre for the gut bacteria to enjoy. In fact, one of the reasons these foods do cause gas and flatulence is the amount and type of this fibre, which produces gas when digested and consumed by the gut bacteria. So, it’s really a matter of choice.
Remember, if you’re taking probiotics, you need your prebiotics too because they act as fuel! I hope this was an informative little piece on just how these foods work in our guts and why we emphasise getting good bacteria so much.
Health Effects & Sources Of Prebiotic Dietary Fibre
Prebiotics (Science Direct)
Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications
Emergent Sources of Prebiotics: Seaweeds and Microalgae
The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-term Health