What happens when you eat fibre?

Let’s say you eat a bowl of raspberries, a handful of nuts or a sachet of INDI Body. Maybe you don’t feel much. Maybe you notice an extra trip to the bathroom.

Even if you don’t notice anything, something amazing is happening inside your gut.

DAY 1: MICROBIOME PARTY 

When your microbes first get a taste of fibre, they throw a little celebration. As they ferment it, they release compounds called short-chain fatty acids (SCFAs)—examples including acetate, propionate, and butyrate.

These SCFAs act like mini superheroes:

• Butyrate fuels and strengthens the gut lining (helping reduce inflammation).
• Acetate enters circulation quickly, providing energy to muscles and tissues.
• Propionate travels to the liver, where it begins nudging metabolism.

Research suggests your microbiome can start shifting within just 24-48 hours of changing your fibre intake.

WEEK 1: LOW AND SLOW 

Consistency is key. Think of fibre as fertiliser for your inner garden—the more regularly you feed your microbes, the stronger and more diverse they’ll become.

As microbes ferment fibre, they also release some gas. This is normal and healthy and a sign that your gut bugs are hard at work. But just like strength training, you don’t start with the heaviest weights. Go low and slow with fibre to let your microbiome adapt. Also, try to spread fibre across meals instead of piling it all into one sitting. For example a tablespoon of chia seeds at breakfast, a sprinkle of nuts/seeds at lunch and a handful of beans at dinner.

By the end of the first week you may notice:

• Feeling fuller for longer (fibre slows digestion, so satiety signals kick in sooner).
• More regular bathroom visits.
• Balanced blood sugar and fewer energy crashes (fibre slows glucose absorption).

MONTH 1: GUT STRENGTHENS 

By the one-month mark, your gut microbiome has shifted into a more balanced state, with beneficial bacteria starting to claim their territory.

What’s happening inside:

• Your gut lining has become stronger and less “leaky,” so fewer unwanted molecules sneak into the blood to trigger the immune system (around 70% of your immune cells live in the gut).
• Inflammation levels start to come down.
• SCFA production is now more steady and reliable.

You may notice:

• Smoother, more consistent poops.
• Fewer sugar cravings.
• Less bloating.

6 MONTHS +: FIBRE FOR LIFE

This is where the real magic happens. With small, consistent fibre habits, your microbiome becomes not only stronger but also more resilient. It’s better at bouncing back from stressors like antibiotics, illness or even a poor night’s sleep.

Over time, high fibre intake is linked with:

• Better insulin sensitivity.
• Lower LDL cholesterol.
• Improved mood and cognitive health (thank you gut–brain connection).
• Reduced risk of type 2 diabetes, colorectal cancer, heart disease, and even all-cause mortality.

All of this, just from an extra handful of raspberries (or whichever berries, vegetables, beans, lentils, whole grain, nuts or seeds your heart desires). It’s one of the simplest, most powerful investments you can make to your long-term health.

For easy ways to add more fibre, check out this blog here.