Nutrition

The Ultimate Guide to Fibre and Gut Health

Why fibre is essential for your microbiome, how much you really need, and the best sources for optimal gut function.

ElenaOctober 20258 min read
The Ultimate Guide to Fibre and Gut Health

Fibre is often called the most important nutrient for gut health, yet most people fall far short of recommended intakes. Understanding the different types of fibre, their unique benefits, and how to increase your intake can transform your digestive health and overall wellbeing.

What Is Fibre?

Fibre is the part of plant foods that your body cannot digest. Unlike proteins, fats, and carbohydrates, fibre passes through your digestive system relatively intact. But far from being useless, this indigestible material plays crucial roles in gut health.

Types of Fibre

Soluble Fibre

Soluble fibre dissolves in water to form a gel-like substance. It's found in:

  • Oats and barley
  • Beans and lentils
  • Apples and citrus fruits
  • Psyllium husk
  • Benefits include:

  • Slowing digestion and promoting fullness
  • Helping regulate blood sugar
  • Lowering cholesterol
  • Feeding beneficial gut bacteria
  • Insoluble Fibre

    Insoluble fibre doesn't dissolve in water. It's found in:

  • Whole grains
  • Nuts and seeds
  • Vegetables (especially skins)
  • Wheat bran
  • Benefits include:

  • Adding bulk to stool
  • Promoting regular bowel movements
  • Preventing constipation
  • Supporting colon health
  • Resistant Starch

    A special type of fibre that 'resists' digestion:

  • Cooked and cooled potatoes, rice, and pasta
  • Green bananas
  • Legumes
  • Whole grains
  • Benefits include:

  • Powerful prebiotic effects
  • Produces beneficial short-chain fatty acids
  • Supports blood sugar regulation
  • Enhances mineral absorption
  • How Much Fibre Do You Need?

    Official recommendations suggest:

  • Women: 25 grams per day
  • Men: 38 grams per day
  • However, our ancestors likely consumed 100+ grams daily. Most people in Western countries consume only 15-20 grams. For optimal gut health, aiming for 30-40 grams is a reasonable goal.

    The Gut Microbiome Connection

    Fibre is the primary food source for your beneficial gut bacteria. When bacteria ferment fibre, they produce:

    Butyrate The primary fuel for colon cells, supporting gut lining integrity and reducing inflammation.

    Acetate and propionate Support metabolic health, appetite regulation, and immune function.

    A high-fibre diet promotes:

  • Greater bacterial diversity
  • More beneficial bacteria
  • Reduced harmful bacteria
  • Lower gut inflammation
  • Best High-Fibre Foods

    Legumes Lentils, chickpeas, black beans (15-20g per cup)

    Whole grains Oats, quinoa, brown rice (4-8g per cup cooked)

    Vegetables Broccoli, Brussels sprouts, artichokes (4-10g per cup)

    Fruits Raspberries, pears, apples with skin (4-8g per serving)

    Nuts and seeds Chia seeds, flaxseeds, almonds (3-10g per ounce)

    How to Increase Fibre Safely

    Increasing fibre too quickly can cause bloating, gas, and discomfort. Follow these guidelines:

  • Increase by 5 grams per week
  • Drink plenty of water (fibre needs fluid to work properly)
  • Spread fibre intake throughout the day
  • Choose whole foods over supplements when possible
  • If you have IBS, work with a practitioner to identify which fibres you tolerate
  • When Fibre Causes Problems

    For some people, particularly those with IBS or SIBO, certain fibres can worsen symptoms. This doesn't mean you should avoid fibre entirely, but rather:

  • Identify which types of fibre you tolerate
  • Address underlying gut issues first
  • Gradually reintroduce fibres as gut health improves
  • Work with a practitioner to create a personalised approach
  • The Bottom Line

    Fibre is fundamental to gut health, yet most people don't get enough. By gradually increasing your intake of diverse fibre sources, you can support a thriving gut microbiome, improve digestive function, and enhance overall health. If you're struggling to tolerate fibre or want guidance on optimising your intake, working with a gut health specialist can help you find the right approach for your unique situation.

    Ready to optimise your gut health?

    Book a free discovery call to discuss your symptoms and find out how personalised gut health support can help you.