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The secret ingredient your gut craves 🧠 fibre!
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The secret ingredient your gut craves 🧠 fibre!

Week 2 of '8 Weeks to a Thriving Gut' series

Dr Emily Leeming PhD's avatar
Dr Emily Leeming PhD
Jan 08, 2025
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The secret ingredient your gut craves 🧠 fibre!
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Welcome back to Week 2 of 8 Weeks to a Thriving Gut!

Download your PDF Fibre Foods Booklet (paid subscribers only).

Last week, we introduced the gut microbiome - a bustling ecosystem inside you that plays a vital role in your digestion, mood, immunity, and overall health.

This week, we’re diving into fibre - your gut microbes’ favourite food.

The big problem? A staggering 90% of us aren’t getting enough of it.

red and white leather handbag
Photo by Towfiqu barbhuiya on Unsplash

Here’s what we’ll cover today:

  • What is fibre? Busting the myth that it’s boring, it’s so much more than brown bread and bland cereals.

  • Why fibre matters: What it does for your gut (and beyond) - and how to eat more of it (with PDF download).

  • Your action for the week: Easy tips to add-in more fibre, with the low and slow method.

bunch of vegetables
Photo by Andres Carreno on Unsplash

What is fibre?

When you hear the word fibre, do you think of dusty wholegrain cereals and cardboard-tasting bread?

You’re not alone. Fibre has a reputation for being boring and bland - but nothing could be further from the truth.

Fibre is a type of carbohydrate, found in exciting, delicious plant foods like:

  • Fruit

  • Veggies

  • Beans, lentils, and legumes

  • Grains

  • Nuts and seeds

brown almond nuts on clear glass bowl
Photo by Usman Yousaf on Unsplash

We’re drastically lacking fibre

  • UK recommendations: Adults should aim for 30g of fibre daily.

  • US recommendations: Based on calorie needs, the guideline is 14g of fibre per 1000 calories. This equates to:

    • 35g/day for men (based on ~2,500 calories).

    • 28g/day for women (based on ~2,000 calories).

But here’s the problem - most of us fall short.

In the UK, we average just under 20g of fibre a day, leaving us with a one-third gap to fill. The US lags even further behind (missing just under half the recommended amount).

This fibre gap is linked to a higher risk of heart disease, type II diabetes, colorectal cancer, digestive issues, and even mental health challenges.

green broccoli

Heart and metabolic health

  • Every 7g of fibre eaten daily, is linked to a 6-9% lower risk of heart disease, stroke, and type II diabetes.

  • Fibre helps slow the release of sugar into your bloodstream (giving you steady energy through the day), and supports healthy cholesterol levels.

Your gut-brain connection

  • Every 5g fibre daily is related to a 5% lower risk of depression.

  • Fibre helps support emotional well-being and boosts memory.

You don’t have the enzymes to digest fibre on your own.

That’s where your gut microbes get involved.

Your gut

  • Fibre helps food move through your gut at the right pace, easing bloating, discomfort and preventing constipation.

  • Every extra 10g of fibre a day is linked to a 10% lower risk of colorectal cancer, similarly, every three servings of whole grains daily is related to a 17% lower risk.

Your gut microbiome

  • When you eat fibre, your gut microbes break it down into powerful molecules called short-chain fatty acids (SCFAs).

  • SCFAs lower excess inflammation, help keep your gut barrier lining healthy, and support your immune system.

orange and green dried leaves
Photo by Jan Huber on Unsplash

Variety matters

Fibre isn’t just one thing - there are a variety of fibre types that have different actions for your health.

No one food contains all the fibre types for a healthy gut. Instead your gut thrives on a variety of plant foods, like fruit, veggies, whole grains, beans, nuts and seeds.

This means you get a mix of fibres that:

  • Feed your ‘good’ gut microbes.

  • Help keep your digestion moving at a nice, steady pace (with a smooth exit into the toilet bowl).

  • Support your heart health, immune system, brain and more.

We’ll cover prebiotic fibres next week.

round green and yellow fruit lot

What foods are high in fibre? (your PDF download)

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