Signs You’re Not Eating Enough Fibre: How to Tell and What to Do

Fibre is an essential part of a balanced diet, supporting everything from healthy digestion to blood glucose control, cholesterol levels, and overall gut health. However, many people struggle to meet their recommended intake, and knowing the signs you’re not eating enough fibre can help you identify whether your diet may need some adjustments.

In the UK, adults are recommended to consume around 30g of fibre per day, yet many people fall short of this target. Low fibre intake can happen for many reasons, including eating fewer whole grains, vegetables, fruits, pulses, nuts, and seeds.

While

is often associated with preventing constipation, its role goes far beyond keeping you regular. Fibre helps nourish beneficial gut bacteria, supports fullness after meals, and contributes to long-term health.

So, what are the signs of low fibre intake, and how can you increase fibre in your diet in a practical and sustainable way?

What Is Fibre and Why Is It Important?

Dietary fibre is a type of carbohydrate found naturally in plant foods. Unlike other carbohydrates, fibre is not fully broken down and absorbed by the body. Instead, it passes through the digestive system, where it provides several important health benefits.

There are two main types of fibre:

Soluble fibre

Soluble fibre dissolves in water to form a gel-like substance in the gut. It can help slow digestion, support stable blood glucose levels, and contribute to healthy cholesterol levels.

Sources of soluble fibre include:

• Oats

• Barley

• Beans and lentils

• Apples

• Berries

• Chia seeds

• Flaxseeds

Insoluble fibre

Insoluble fibre adds bulk to stools and helps food move through the digestive system. It is particularly important for maintaining regular bowel movements.

Sources of insoluble fibre include:

• Wholemeal bread

• Brown rice

• Wholegrain cereals

• Vegetables

• Nuts and seeds

Most plant foods contain a combination of both types of fibre, which is why eating a varied diet is important.

How Much Fibre Should You Eat Each Day?

The recommended daily fibre intake for adults in the UK is:

• Adults: approximately 30g per day

• Children: requirements vary depending on age

However, fibre intake should be increased gradually, especially if your current intake is low. Increasing fibre too quickly may lead to bloating, gas, or abdominal discomfort.

A simple way to increase fibre intake is to make small swaps, such as:

• Choosing wholegrain bread instead of white bread

• Adding beans or lentils to meals

• Including vegetables at lunch and dinner

• Choosing fruit as a snack

• Adding nuts or seeds to yoghurt or porridge

Signs You’re Not Eating Enough Fibre

If your diet is low in fibre, your body may provide several clues. Here are some common signs of low fibre intake to look out for.

1. Constipation or Irregular Bowel Movements

One of the most well-known signs you’re not eating enough fibre is constipation.

Fibre helps increase stool bulk and supports movement through the digestive tract. When fibre intake is too low, stools may become harder, smaller, and more difficult to pass.

You may notice:

• Fewer bowel movements than usual

• Straining when going to the toilet

• Hard or pellet-like stools

• Feeling like your bowels have not fully emptied

Increasing fibre alongside adequate fluid intake can help support healthier bowel movements.

Good fibre-rich options include:

• Porridge oats

• Wholegrain cereals

• Lentils and beans

• Vegetables

• Fruit with the skin, where appropriate

2. Feeling Hungry Soon After Eating

Fibre plays an important role in helping you feel satisfied after meals.

High-fibre foods often take longer to digest and can slow the movement of food through the digestive system. This may help you feel fuller for longer and support appetite regulation.

If you frequently experience:

• Feeling hungry shortly after meals

• Regular snacking despite eating enough food

• Difficulty feeling satisfied after eating

your diet may benefit from including more fibre-rich foods.

Try adding:

• Chickpeas to salads

• Vegetables to meals

• Nuts and seeds to snacks

• Wholegrain carbohydrates such as brown rice or wholemeal pasta

3. Poor Gut Health or Digestive Changes

Your gut contains trillions of microorganisms that play an important role in digestion and overall health. Fibre acts as a food source for beneficial gut bacteria, helping them produce compounds that support gut health.

A low-fibre diet may contribute to:

• Reduced the variety of gut bacteria

• Changes in bowel habits

• Increased digestive discomfort

Different types of fibre feed different bacteria, so eating a wide variety of plant foods is beneficial.

Aim to include a “rainbow” of plant foods across the week, including:

• Different coloured vegetables

• Fruits

• Whole grains

• Pulses

• Nuts and seeds

4. Your Diet Lacks Variety

A diet naturally low in fibre often contains fewer plant-based foods.

If most of your meals are based around:

• White bread

• Refined cereals

• Processed snacks

• Low amounts of fruit and vegetables

you may not be getting enough dietary fibre.

A balanced diet should include a variety of plant foods, as these provide fibre alongside important vitamins, minerals, and antioxidants.

A helpful goal is to include:

• 5 portions of fruit and vegetables daily

• Wholegrain carbohydrates regularly

• Beans, peas, and lentils throughout the week

5. Blood Glucose Levels Feel Difficult to Manage

Fibre, particularly soluble fibre, can help slow digestion and the release of glucose into the bloodstream.

Including fibre alongside carbohydrate-containing foods can support a slower, steadier rise in blood glucose levels.

Low-fibre meals may include more refined carbohydrates, which can be digested more quickly.

Examples of adding fibre to meals include:

Instead of:

• White toast with jam

Try:

• Wholegrain toast with peanut butter and fruit

Instead of:

• Plain pasta with sauce

Try:

• Wholemeal pasta with vegetables and beans or lentils

Benefits of Eating Enough Fibre

Meeting your recommended fibre intake can support many aspects of health.

Supports digestive health

Fibre helps maintain regular bowel movements and supports a healthy gut environment.

Supports heart health

Some types of fibre can help reduce cholesterol levels when included as part of a balanced diet.

Helps maintain a healthy weight

High-fibre foods can improve fullness, helping support appetite regulation and balanced eating patterns.

Supports healthy blood glucose management

Fibre slows digestion, helping promote steadier energy levels.

How to Increase Your Fibre Intake

If you recognise some of these signs, you’re not eating enough fibre. The good news is that increasing your intake does not need to be complicated.

Start with small changes

Suddenly increasing fibre can cause bloating or discomfort, so gradually build up your intake.

Simple swaps include:

Breakfast

Instead of:

• Low-fibre cereal

Try:

• Porridge topped with berries and chia seeds

• Wholegrain cereal with fruit

Lunch

Instead of:

• White bread sandwich

Try:

• Wholemeal bread with salad and a protein filling

• A bean or lentil-based soup

Dinner

Instead of:

• White pasta or rice

Try:

• Wholemeal pasta

• Brown rice

• Quinoa

• Adding beans or vegetables

Snacks

Choose:

• Fruit

• Nuts

• Seeds

• Hummus with vegetables

• Wholegrain crackers

Can You Eat Too Much Fibre?

Although fibre is important, more is not always better.

Increasing fibre too quickly may cause:

• Bloating

• Gas

• Stomach discomfort

• Changes in bowel habits

To support digestion:

• Increase fibre gradually

• Drink enough fluids

• Include a variety of fibre sources

• Listen to your body

Some individuals with gastrointestinal conditions, such as irritable bowel syndrome (IBS), may need personalised advice about fibre intake, as different types of fibre can affect symptoms differently.

FAQ: Signs You’re Not Eating Enough Fibre

1. What are the main signs you’re not eating enough fibre?

Common signs of low fibre intake include constipation, irregular bowel movements, feeling hungry soon after meals, reduced intake of fruits and vegetables, and digestive changes. However, symptoms can vary between individuals depending on overall diet, lifestyle, and health.

2. How can I increase my fibre intake without getting bloated?

Increase fibre gradually rather than making large changes overnight. Add one additional high-fibre food at a time, such as a portion of vegetables, fruit, oats, or pulses. Drinking enough fluids is also important, as fibre works best when combined with adequate hydration.

3. What foods are highest in fibre?

Some of the best fibre-rich foods include beans, lentils, chickpeas, oats, wholegrain bread, wholemeal pasta, vegetables, fruits, nuts, seeds, and high-fibre cereals. Including a variety of these foods throughout the day can help you reach the recommended 30g of fibre per day.

If you are unsure how much fibre you need or have ongoing digestive symptoms, speaking with a registered dietitian can help you find an approach that works for your individual needs.