How Much Fibre Do You Need Per Day? Plus Signs You’re Not Getting Enough

The rundown on fibre: 

• Most Australians don’t get enough fibre, largely due to modern diets that rely more on highly processed foods and fewer fibre-rich plant foods.
• Adults generally need around 30 g of fibre per day for men and 25 g per day for women, though needs vary by age and lifestyle.
• Low fibre intake may show up as digestive discomfort, irregular bowel habits or feeling hungry soon after meals.

When we think about balanced meals, fibre isn’t always the first thing that comes to mind. It doesn’t have the same spotlight as protein or healthy fats, yet it’s a key part of how meals come together and how satisfied you feel afterwards. Fibre can help add structure and variety to the plate and can influence how full you feel after eating. 

In fact, most Australians don’t consume enough fibre¹. Changes in the way we eat, including a greater reliance on highly processed foods and fewer fibre-rich plant foods, mean fibre often drops off the plate without us realising^2,3.

In this article, we break down how much fibre you need per day, what it does in the body and common signs you may not be getting enough. 

What is fibre? 

Fibre is a type of carbohydrate found in plant foods that the body doesn’t fully digest. Instead of being broken down and absorbed, fibre moves through the digestive system, playing an important role in keeping things running smoothly². While fibre is best known for its role in digestion, it can also support other aspects of wellbeing, including immune function and gut health¹.

Common sources of fibre include plant foods like vegetables, fruits, grains, nuts, seeds and legumes¹.

The different types of fibre

There are two different types of fibre that work in slightly different ways. 

• Soluble fibre absorbs water during digestion, helping to slow the movement of food through the stomach. This can help support feelings of fullness. It’s also been shown to support healthy cholesterol and blood sugar levels¹. 
• Insoluble fibre does not dissolve in water and helps add bulk as food moves through the digestive system. This supports regular bowel movements and helps maintain a healthy bowel environment¹.

Both soluble and insoluble fibre are found naturally in plant foods. Fruits and vegetables are common sources of soluble fibre, while wholegrain breads and cereals, bran, nuts and seeds tend to provide more insoluble fibre¹ ². Most whole foods contain a mix of both types.

What does fibre do in the body? 

Fibre supports several key functions that help the body feel balanced day to day. But why exactly do we need fibre? Here’s a breakdown of how fibre works. 

Supports digestion and gut health
One of the main fibre benefits is its role in keeping the digestive system working smoothly. It supports gut movement and contributes to a healthy gut environment, including the balance of gut microorganisms, which play a role in overall health^1,4.

Helps maintain bowel regularity
Dietary fibre absorbs water and adds bulk to stools, which helps soften them and make them easier to pass. This supports regular bowel movements and helps reduce the risk of constipation^1,4,5.

Contributes to feelings of fullness after meals
Fibre slows digestion, which can help meals feel more satisfying and keep you feeling fuller for longer. This can support appetite control as part of everyday eating¹.

Supports cholesterol and blood sugar balance
Soluble fibre has been shown to help lower cholesterol levels by binding bile acids and helping remove them from the body4. Fibre can also help support more stable blood sugar levels after meals¹.

How many grams of fibre do you need per day?

Fibre needs aren’t one-size-fits-all. How much fibre you need each day can vary depending on factors such as age, gender and lifestyle. That said, general intake guidelines provide a helpful benchmark, particularly as many people fall short.

• Men aged 18 and over need around 30g per day.
• Women aged 18 and over need around 25g per day¹. 

Despite these targets, many adults do not reach recommended fibre intakes. On average, most Australians consume closer to 20–25g of fibre per day, which means intake often falls below what the body needs to support digestion and overall wellbeing⁴.

Getting closer to recommended fibre intakes usually comes down to food choices rather than counting grams. Regularly including food sources of fibre such as vegetables, fruits, wholegrains, legumes, nuts and seeds across meals and snacks can help fibre intake add up naturally. Small, consistent changes often make the biggest difference.

What happens when you eat enough fibre?

Meeting your daily fibre needs can make a noticeable difference to how your body feels day to day^1,5. Here's what you might experience:

• More comfortable digestion
• Improved bowel regularity
• Feeling fuller for longer after meals
• Support for cholesterol and blood sugar balance

Low fibre symptoms 

When fibre intake is consistently low, the body may start to send subtle signals. These signs can be easy to overlook on their own, but together they may suggest you’re not getting enough fibre in your diet.

Some common signs associated with low fibre intake include:

• Digestive discomfort or constipation: Diets low in fibre have been linked with constipation and less comfortable digestion, as fibre helps add bulk and support regular bowel movements⁴.
• Irregular bowel habits: Fibre plays an important role in digestive health and regularity. When intake is low, bowel movements may become less predictable or less frequent¹.
• Feeling hungry soon after eating: Fibre contributes to feelings of fullness after meals. Without enough fibre, hunger may return sooner between meals⁶.
• A general sense that digestion feels ‘off’: Fibre supports gut movement and a healthy digestive environment. Lower fibre intake may affect how settled digestion feels overall².

Can you have too much fibre?

Fibre is an important part of a balanced diet, but increasing intake too quickly can sometimes lead to short-term digestive discomfort. Too much fibre, especially when added quickly, can cause temporary symptoms as the digestive system adjusts.

Some common too much fibre symptoms can include⁷:

• Bloating or a feeling of fullness
• Increased gas (wind)
• Abdominal discomfort or cramping
• Changes in bowel habits
  
  

These effects are usually linked to how quickly fibre is introduced, rather than fibre itself. A sudden jump from a low-fibre diet to a high-fibre diet can overwhelm the digestive system for a short time, especially if fluid intake does not increase alongside it^1,4,7.

Hydration also matters. Fibre absorbs water as it moves through the gut, so not drinking enough fluids can make discomfort more likely. Instead, try to drink plenty of water to help fibre move through the digestive system comfortably^1,4.

The key takeaway is balance. Increasing fibre slowly, paying attention to how your body responds, and staying well hydrated can help you enjoy the benefits of fibre without unnecessary discomfort.

Supporting your fibre intake as part of a balanced routine

Getting enough fibre works best when it’s part of a broader set of everyday habits. Fibre doesn’t work in isolation. It’s most effective when supported by regular meals, enough fluids, and a varied intake of whole foods.

For more guidance on building everyday habits that support your wellbeing, explore related articles like a guide to good gut health on the Swisse Wellness Hub.

References:

1. Nutrition Australia. (2026). Fibre. Available at: https://nutritionaustralia.org/resources/fibre-2/
2. Barber, T. M., Kabisch, S., Pfeiffer, A. F. H., & Weickert, M. O. (2020). The Health Benefits of Dietary Fibre. Nutrients, 12(10), 3209. https://doi.org/10.3390/nu12103209
3. Daley, S. F., & Shreenath, A. P. (2025). The Role of Dietary Fiber in Health Promotion and Disease Prevention: A Practical Guide for Clinicians. StatPearls Publishing.
4. Better Health Channel. (2025). Dietary fibre. Available at: https://www.betterhealth.vic.gov.au/health/healthyliving/dietary-fibre
5. Suresh, A., Shobna, Salaria, M., Morya, S., Khalid, W., Afzal, F. A., et al. (2024). Dietary fiber: an unmatched food component for sustainable health. Food and Agricultural Immunology, 35(1). https://doi.org/10.1080/09540105.2024.2384420
6. Slavin, J., & Green, H. (2007). Dietary fibre and satiety. Nutrition Bulletin, 32, 32–42.
7. Daley, S. F., & Shreenath, A. P. (2025). The Role of Dietary Fiber in Health Promotion and Disease Prevention: A Practical Guide for Clinicians. StatPearls Publishing. PMID: 32644459