The Importance of Fibre: The Scoop on Glucomannan

When it comes to nutrition, fibre is one of my favourite nutrients to talk about as it is one of the most important yet often overlooked nutrients when it comes to long-term health. It’s a key player in promoting healthy digestion, heart health, blood sugar regulation, and even disease prevention. Despite its crucial role, most people fail to consume enough fibre daily. The British Nutrition Foundation recommends 28–40g of fibre per day for adults, yet most of us only manage around 18g. 

Increasing fibre intake isn’t just about improving digestive health, though it certainly helps with that. It has a direct impact on the prevention of several chronic conditions, including type 2 diabetes, heart disease, Alzheimer’s disease, and some cancers. Research has shown that consuming a higher fibre diet is associated with a longer lifespan, lower risk of heart disease, and a 10% reduction in the risk of death from any cause with just a 10g increase in daily fibre intake. This highlights the incredible benefits of adding more fibre to your meals.

The relationship between fibre and health is complex, as there are many different types of fibre, each with its unique properties and effects on the body. These can be classified into three categories: solubility, viscosity, and fermentability. Each type of fibre works differently, but together, they support a wide range of health benefits.

What Is Fibre?

Fibre is a type of carbohydrate found primarily in plant foods. Unlike other carbohydrates, it’s not digested or absorbed by the body. Instead, it passes through the small intestine undigested and makes its way to the large intestine. It serves a variety of purposes along the way, including adding bulk to stool, aiding in bowel movements, removing excess hormones and nourishing the beneficial bacteria in the gut.

There are three main types of fibre: soluble and insoluble. Each type offers different benefits and is found in various food sources:

1. Soluble Fibre: This type dissolves in water and forms a gel-like substance in the intestines. Soluble fibre is particularly helpful in managing blood sugar levels, as it slows the absorption of sugar into the bloodstream. It also lowers LDL (“bad”) cholesterol, contributing to better heart health. Soluble fibre is found in foods such as oats, barley, fruits like apples and oranges, legumes, and some vegetables like carrots and Brussels sprouts.

2. Insoluble Fibre: Unlike soluble fibre, insoluble fibre does not dissolve in water. It adds bulk to stool, helping to speed up the passage of food through the digestive system. This type of fibre is essential for preventing constipation and maintaining regular bowel movements. Common sources of insoluble fibre include whole grains, nuts, seeds, and vegetables like spinach, kale, and broccoli.

3. Fermentable fibres: This serves as a food source for the beneficial bacteria in our gut. These are also known as prebiotic fibres, as they promote the growth of healthy gut microbiota. Prebiotic fibres can improve gut health, boost immunity, and aid in the production of beneficial compounds like short-chain fatty acids (SCFAs) that support the digestive tract and immune system.

Health Benefits of Fibre

Fibre is not just about preventing constipation - its benefits go far beyond that. By incorporating both soluble and insoluble fibre into your diet, you can enjoy a range of health improvements, including:

1. Digestive Health: Insoluble fibre helps keep the digestive system moving by adding bulk to stool and supporting bowel regularity. Soluble fibre nourishes beneficial gut bacteria, enhancing gut microbiota health. Together, these types of fibre promote a balanced, well-functioning digestive system.

2. Blood Sugar Regulation: Soluble fibre slows the absorption of sugar into the bloodstream, helping to prevent sharp spikes in blood sugar levels after meals. This is particularly important for people managing type 2 diabetes or those at risk of developing the condition. Studies have shown that a fibre intake of 30g per day can reduce the risk of type 2 diabetes by 21%, compared to those who consume only 20g.

3. Heart Health: One of the most significant benefits of fibre is its ability to lower cholesterol. Soluble fibre binds to bile acids in the digestive system, helping to remove excess cholesterol from the body. This lowers LDL cholesterol levels and reduces the risk of heart disease and stroke.

4. Weight Management: Fibre-rich foods are naturally filling and take longer to digest, which helps to control appetite and reduce overeating. Foods high in fibre, such as fruits, vegetables, and whole grains, are more filling and lower in calories than their refined counterparts, making them a key component of any weight management plan.

5. Cancer Prevention: Studies have suggested that a higher fibre intake is linked to a lower risk of colorectal cancer. Fibre helps by binding to and removing harmful substances in the digestive tract, reducing inflammation, and supporting healthy bowel function.

6. Longevity: Research consistently shows that people with a higher fibre intake tend to live longer and experience better overall health. A 10g increase in fibre intake has been associated with a 13% lower risk of heart disease and a 9% reduced risk of death from cancer. It’s clear that fibre is a powerful tool for supporting a long, healthy life.

Fibre Intake Recommendations and How to Increase It

The British Nutrition Foundation recommends a daily intake of 28–40g of fibre for adults, but most people consume far less. Increasing your fibre intake is easier than it might seem, and even small changes can make a big difference. Here are some tips to help boost your fibre intake:

1. Add Fibre to Your Meals: Start your day with fibre-rich breakfast options such as porridge, wholegrain cereals, or Weetabix. Add fruit, nuts, and seeds to your meals, or incorporate pulses like lentils, beans, and chickpeas into dishes such as stews, curries, and salads.

2. Swap to Wholegrain Options: Replace refined grains with whole grains, such as switching white bread for wholemeal or granary bread, white pasta for wholewheat, and white rice for brown rice.

3. Freeze your bread and cook, then cool refined grains: Freezing and thawing white bread, or cooking and cooling carbohydrates like pasta and rice, alters their structure through a process called retrogradation. This process transforms the starch into resistant starch, a type of fermentable fibre that nourishes your beneficial gut bacteria.

4. Choose High-Fibre Snacks: Snacking on raw vegetables with hummus, rye crackers, or a handful of unsalted nuts can be a great way to add fibre to your day.

5. Eat the Skin: Many fruits and vegetables contain a significant amount of fibre in their skin. Whenever possible, leave the skin on when eating apples, pears, potatoes, carrots, and other fibre-rich produce.

6. Keep Frozen Vegetables on Hand: Frozen vegetables are a convenient and affordable way to make sure you’re always able to add fibre to your meals.

When increasing fibre intake, it’s essential to also drink plenty of water, as this helps the fibre move through your digestive system and prevents discomfort such as bloating or constipation.

For individuals with gastrointestinal (GI) issues, it's important to increase fibre gradually and seek support from a healthcare professional. Some types of fibre, particularly insoluble and fermentable fibre, may exacerbate symptoms like bloating, gas, or diarrhoea. Working with a dietitian can help tailor a fibre intake plan that suits your needs and optimises digestive health.

Glucomannan and Its Role in Weight Management

While fibre from whole foods should always be the first choice, supplements like glucomannan can also play a role in meeting your daily fibre needs. Derived from the root of the konjac plant, glucomannan is a water-soluble fibre that is exceptionally viscous, meaning it forms a thick gel when mixed with water. This gel-forming property helps to promote a feeling of fullness, making it easier to control appetite and manage weight.

However, glucomannan does not work unless it is taken before meals. Ideally, you should consume it 15–30 minutes before eating, along with 1–2 glasses of water. This allows the glucomannan to expand in the stomach, creating a sense of fullness and helping to control hunger.

It’s essential to drink plenty of water when consuming glucomannan to prevent it from swelling in the throat or oesophagus, which could lead to choking or a blockage. Some individuals may experience mild side effects, such as bloating, flatulence, or soft stools, but these tend to be rare and can be mitigated by gradually increasing the amount taken.

While glucomannan can support weight loss efforts, it should never be seen as a miracle solution. For lasting weight management, it should be combined with a healthy, balanced diet and regular physical activity. It’s also important to be mindful that glucomannan can interfere with the absorption of certain medications, including diabetes medications like sulfonylureas. To avoid this, it’s recommended to take medications at least four hours before or one hour after consuming glucomannan.

Conclusion

Fibre is one of the most powerful and versatile nutrients available to us. From promoting digestive health and heart health to preventing chronic diseases and supporting longevity, the benefits of fibre are vast and well-documented. Despite this, most people fail to get enough in their diets. By prioritising fibre from whole food sources like fruits, vegetables, whole grains, and legumes, you can significantly improve your health and reduce the risk of various diseases.

For those who struggle to meet their fibre needs or are looking for a bit of extra help with appetite control, supplements like glucomannan can be a useful addition. However, they should not replace a balanced diet and a healthy lifestyle. Sustainable, long-term results come from making gradual changes to your eating habits and lifestyle, and fibre is a key component in that journey.

By embracing a fibre-rich diet, you’ll not only support your digestive health but also boost your overall well-being. Take small steps, increase your fibre intake gradually, and enjoy the long-term benefits this humble yet powerful nutrient has to offer.

Sources: 

• https://www.sciencedirect.com/science/article/pii/S0002916522028131?via%3Dihub

• https://pmc.ncbi.nlm.nih.gov/articles/PMC10579821/

• https://pmc.ncbi.nlm.nih.gov/articles/PMC6537190/

• https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2023.1153165/full

• https://www.sciencedirect.com/science/article/abs/pii/S0144861724004922?via%3Dihub

• https://www.bda.uk.com/resource/fibre.html

• https://www.sciencedirect.com/science/article/abs/pii/S2451847620300968