I love the way naturopath and microbiome researcher Dr Jason Hawrelak describes our gut.
You’re the farmer. Your gut microbiome is your garden.
What grows depends on what you feed it.
Why your probiotic isn’t moving in
Most people assume that when they swallow a probiotic, the good bacteria settle into the bowel and stay there for good.
For most strains, they don’t. They pass through, do some useful work on the way, and then they’re gone.
That doesn’t make probiotics useless. I use them often, and the right strain at the right time can make a real difference. But no probiotic can build a thriving garden if you’re not feeding the bacteria already living there.
Fibre is the fertiliser
This surprises a lot of people: there’s no fibre in meat, chicken, fish, eggs or dairy. Fibre only comes from plants.
Vegetables, herbs, fruit, berries, nuts, seeds, legumes, whole grains and resistant starch all feed different microbes. And different microbes have different favourite foods.
That’s why variety matters so much. Eating the same three vegetables every day feeds the same few bacteria. A wide range of plants across the week feeds a whole ecosystem.
Try this: count how many different plants you eat in a week. Herbs, spices, nuts and seeds all count. Then try to beat it next week.
Prebiotics: the selective fertiliser
Dr Hawrelak calls prebiotics selective fertilisers. Not all fibre counts. Prebiotics specifically feed the beneficial bacteria you want more of.
Great sources include garlic, onion, leeks, asparagus, artichokes, legumes and foods rich in resistant starch, like cooked and cooled potatoes or rice and slightly green bananas.
How much fibre?
I aim for around 40 to 45 g of fibre a day for most adults, adjusted to the person.
Most Australians fall well short. Only about 1 in 4 adults eat even the basic recommended amount, fewer than 1 in 5 reach the higher target linked with lower chronic disease risk, and just 6.5% eat enough vegetables.
The funny thing is, most people I see think their fibre intake is pretty good. Most are getting around half of what I’d like to see.
The number is only half the story. Forty grams from a handful of foods isn’t the same as forty grams from a wide variety of plants.
If your diet is low in fibre now, build up gradually. Jumping straight to 40 g is a fast track to bloating. And if you have IBS, SIBO or a sensitive gut, the type and amount of fibre needs to be tailored to you. That’s exactly where I can help.
My list of the best fibre and prebiotic foods
Legumes and beans are the fibre champions. A cup of cooked lentils has around 16 g of fibre, black beans around 15 g and chickpeas around 12 g. That’s roughly what you’d get from three cups of cooked broccoli. One cup of legumes gets you more than a third of the way to 40 g.
They’re also natural prebiotics, rich in resistant starch and packed with plant protein. If you make one change after reading this, add a serve of legumes every day.
Here’s my shortlist. Rotate through as many as you can each week, and remember: the more variety, the bigger your garden grows.
- Legumes and beans (your number one fibre source): lentils, chickpeas, black beans, kidney beans, cannellini beans, split peas, edamame and tempeh.
- Other fibre heavy hitters: raspberries (around 8 g a cup), pears with the skin on, quinoa, buckwheat, and chia and flaxseeds.
- Prebiotic superstars: garlic, onion, leeks, asparagus, globe and Jerusalem artichokes, dandelion greens, slightly green bananas and pistachios.
- Polyphenol powerhouses: these feed beneficial bacteria like Akkermansia and Bifidobacteria. Think blueberries, red onion, purple rice, black beans, skin-on almonds, extra virgin olive oil, green tea and cocoa.
- Gentler options for a sensitive gut: kiwifruit, oranges, buckwheat, brown rice, firm tofu, pomegranate, carrots, macadamias and small serves of canned chickpeas.
What does 40 g look like on a plate? Buckwheat porridge with chia, berries and pistachios for breakfast. A lentil and roast vegetable salad for lunch. A tempeh or tofu stir-fry with brown rice and greens for dinner. That’s your 40 g, and then some.
Download my free Good Gut Guide
Want it all in one place? My Good Gut Guide is a 7-page download with everything you need to feed your gut garden:
- a printable 30 plants a week tracker
- the best fibre, prebiotic, polyphenol, pectin and ellagic acid foods
- how to build up your fibre without the bloat
- sleep, stress and lifestyle tips for a healthier microbiome
- three easy gut-loving recipes
Want to see what’s actually growing in your garden?
You can guess what’s happening in your gut, or you can find out.
GutIQ Metagenomic Mapping uses advanced DNA sequencing to identify more than 28,000 microbial species in your gut, including bacteria, fungi and viruses. Most stool tests only look for a short list of usual suspects. This is the most detailed map of your gut garden available.
It also shows:
- butyrate and other short-chain fatty acids: how well your bacteria are feeding your gut lining
- beta-glucuronidase: a clue to whether oestrogen is being cleared or recycled
- zonulin: a marker of gut barrier integrity, often called “leaky gut”
- calprotectin: inflammation in the bowel
- secretory IgA: your gut’s front-line immune defence
- pancreatic elastase and steatocrit: how well you’re digesting food and absorbing fat
It’s worth considering if you have bloating, gas, constipation, loose stools or IBS, food reactions, hormone symptoms, skin issues, low energy, an autoimmune condition, or a long history of antibiotics or reflux medication.
