Why fibre is essential for heart health

But first, what is fibre?

Dietary fibre is a component of plant-based foods that is not digested in the small intestine, but instead passes through to the large intestine where it is fermented by the bacteria that make up our gut microbiome. However, not all fibre is the same, in fact there are two main types of fibre:

Soluble fibre

As the name suggests, this type of fibre absorbs water like a sponge and forms a gel-like substance in the gut. Soluble fibre fuels the gut microbiome, helps to slow the rate of digestion which can support blood sugar management and can reduce LDL (“bad”) cholesterol. Foods that are high in soluble fibre include: oats, legumes, lentils, barley, psyllium husk and some fruits and vegetables.

Insoluble fibre

Unlike soluble fibre, this doesn’t absorb fluids but instead adds bulk to the stool and supports movement through the digestive system. This has a more indirect impact on heart health. Foods high in insoluble fibre include wholegrains, nuts, seeds and the skin on fruit and vegetables.

How does fibre support heart health?

Fibre can support our heart health in a number of different ways including:

Lowering “bad” cholesterol levels

Soluble fibre can help to lower LDL cholesterol levels in the bloodstream. This is beneficial as elevated LDL cholesterol is a major risk factor for heart disease. Soluble fibre acts like a sponge, binding to bile acids (which are made from cholesterol) and allowing them to be excreted rather than re-absorbed. Foods high in soluble fibre include: oats, barley, legumes and psyllium husk.

Supporting stable blood sugar levels

Managing blood sugar levels is an important factor in reducing cardiovascular disease risk. Over time, high blood sugar levels that can occur due to poorly managed diabetes can damage the blood vessels in the heart and increase the risk of developing fatty deposits. Choosing low-GI, fibre-rich carbohydrates, and including adequate fibre with meals and snacks can help to slow the digestion of carbohydrates, and therefore support a more gradual rise in blood sugar levels after a meal. Aim to fill ¼ of your plate with fibre-rich carbohydrates and ½ of your plate with plenty of colourful, non-starchy vegetables.

Anti-inflammatory benefits

Inflammation and heart disease are closely linked, so adopting an anti-inflammatory style of eating can also be beneficial for heart health. An anti-inflammatory diet prioritises plant-based fibre-rich foods such as fruit, vegetables, nuts/seeds, legumes and wholegrains, while limiting highly processed foods. Increasing your intake of fibre-rich foods not only aligns with an anti-inflammatory eating pattern, but also supports a healthier gut microbiome, improves cholesterol management, helps regulate blood sugar levels and supports weight management. All of these factors contribute to reducing inflammation in the body and therefore support your heart health.

How much fibre do we need?

To support our heart health, gut health and overall health, we should be aiming for a minimum of 25-30g of fibre per day. However, the majority of Australians are not meeting this amount. So, how can we consume more fibre to support our heart health?

Simple ways to increase your fibre intake

When it comes to increasing fibre intake, the goal is to increase it gradually over time to avoid unpleasant side-effects. It’s also important to keep up adequate fluids - aim for at least 2-3 litres daily. Some simple swaps to increase your fibre intake include:

• Swapping white bread to wholemeal or wholegrain bread
• Swapping regular pasta to wholemeal or pulse-pasta
• Adding canned legumes into your mince-based dishes such as lentils in a bolognese, or black beans into a Mexican mince
• Aiming for ½ plate of vegetables alongside a source of lean protein and fibre-rich carbohydrates at main meals
• Adding nuts and seeds on top of cereal, yoghurt or salads for some extra crunch and fibre

Small and sustainable for long term heart health

Increasing your fibre intake is a simple and effective way to support your heart health, as well as many other aspects of your health and well-being. Focus on increasing your intake slowly and try to incorporate more plant-based foods into your usual routine. The goal is to create small, sustainable changes to support your heart health in the long-term!