Within the fitness space there can be a tendency to think of fibre as something that’s just functional. Important, of course, but often its impact is only framed around digestion.
In reality, fibre plays a far broader role in how your body performs and how you feel day to day, influencing variables like energy stability and appetite regulation through to long-term metabolic health. For anyone already investing in their training, recovery, and overall wellbeing, a high fibre diet matters more than you might think. It’s one of the simplest ways to bring more consistency to your nutrition, without adding complexity.
In this guide, we’ll take a closer look at what fibre does, why it matters, and how to build a high fibre diet in a way that fits naturally into your routine.
What is fibre and why it matters
Fibre is a type of carbohydrate that is naturally sourced from foods like wholegrains, beans, nuts and more.
At its core, dietary fibre is the part of plant foods your body can’t fully digest. Rather than being absorbed, it moves through the digestive system, interacting with everything along the way.
This process is what makes fibre so valuable. It slows digestion, supports beneficial gut bacteria, and helps regulate how nutrients enter the bloodstream. Over time, these effects compound, influencing energy levels, hunger signals, and metabolic health.
It’s worth understanding that fibre isn’t one single thing, and while it is often grouped together, different types have different roles. Broadly, fibre falls into two categories:
- Soluble fibre: This dissolves in water and forms a gel-like substance, helping to slow digestion and regulate blood sugar and cholesterol.
- Insoluble fibre: This adds bulk and supports regular movement through the digestive system.
Most whole foods contain a combination of both, which is why variety matters more than focusing on a single source.
Why intake is often lower than expected
You might read this and think you’re easily hitting your daily fibre requirements. Yet, even among people who eat relatively well, fibre intake tends to fall short. In the UK, the recommendation sits at around 30g per day, yet average intake is closer to 18–20g.
This isn’t usually down to poor habits. More often, it reflects modern eating patterns:
- A strong focus on high-protein meals can reduce the variety of plant foods in a diet, lowering fibre intake over time.
- A reliance on staples like white bread and pasta contain less fibre than wholegrain alternatives, making fibre intake harder to reach.
- Quick, convenient meals often lack the whole ingredients needed to support adequate fibre intake.
The result isn’t a complete absence of fibre, but it does lead to a gradual shortfall below the 30g recommendations. Each meal might seem balanced in isolation, but across a full day or week, intake consistently sits below where it needs to be.
The Key Benefits of a High Fibre Diet
A high fibre diet supports several key areas of health at the same time:
Gut health and microbiome support
As previously mentioned, fibre’s most recognised role is in digestion, but its impact actually goes deeper than that.
Certain fibres act as prebiotics, feeding beneficial gut bacteria. These bacteria produce compounds known as short-chain fatty acids (SCFAs), including butyrate, which plays a role in maintaining the integrity of the gut lining and regulating inflammation.
A 2019 review published in The Lancet found that higher dietary fibre intake was consistently associated with improved gut health markers and reduced risk of several chronic conditions. The key takeaway wasn’t a single “superfood”, but the cumulative effect of consistent fibre intake over time.
There’s also increasing interest in how microbiome diversity influences overall health. A more varied intake of fibre tends to support a more diverse gut environment, which is linked to better resilience and function.
For those looking to improve their training routines and hit new PBs, a well-functioning gut is central to recovery. This is because fibre supports the gut environment, which in turn affects how efficiently nutrients are absorbed.
More stable energy levels
When it comes to your energy, it isn’t just about calorie intake. It’s also key to ensure your body can effectively process these calories. This is where fibre can be highly beneficial.
This is because fibre slows the digestion of other carbohydrates, leading to a more gradual release of glucose into the bloodstream. This helps avoid the sharp spikes and dips that can come from highly refined meals. Studies also show that diets higher in fibre are associated with improved glycaemic control, even in otherwise healthy individuals.
In practical terms, this often leads to:
- More consistent energy across the day
- Fewer mid-afternoon crashes
- Reduced reliance on quick fixes like sugar or caffeine
For those balancing work, training, and recovery, the more stable blood sugar levels provided by fibre mean more consistent energy availability. This can translate into better training sessions, particularly for longer or more demanding workouts.
Appetite regulation
High fibre foods tend to be more filling due to their volume and slower digestion. At the same time, they influence hormones involved in hunger and fullness, including ghrelin and peptide YY.
There’s also a hormonal aspect to this. Fibre-rich foods can influence the release of satiety hormones, helping your body better recognise when it’s full. This creates a more sustainable approach to body composition. Instead of relying on weight loss restriction, your diet supports appetite regulation more naturally.
Heart Health and Long-Term Outcomes
In addition to the shorter-term health and wellness benefits, fibre intake also has a beneficial impact on long-term health.
Soluble fibre, in particular, has been shown to help reduce LDL cholesterol by binding to cholesterol in the digestive system and aiding its removal. Large cohort studies have consistently linked higher fibre intake with a reduced risk of cardiovascular disease and type 2 diabetes. This is partly due to improved blood sugar regulation and partly due to the broader metabolic benefits of a fibre-rich diet. One study in particular by the BMJ found that each additional 7g of fibre per day was associated with a 9% reduction in cardiovascular disease risk.
These outcomes aren’t immediate, but they reinforce the role of fibre as a long-term investment in health.
High Fibre Diet Foods
We’ve written about his previously (see here for our guide on high fibre foods) but in short, building a high fibre lifestyle doesn’t require a complete overhaul of your current diet. It’s instead about increasing variety and making more intentional choices within your existing routine. Below we have outlined some key foods that can help increase fibre intake.
Whole grains
Oats, brown rice, quinoa, and wholegrain bread provide a steady source of fibre while supporting sustained energy. They’re an easy upgrade from refined grains and tend to be more filling.
Fruits and vegetables
Eating more fruit and vegetable is one of the simplest ways to raise fibre intake.
A useful approach is to focus on variety:
- Berries and apples for convenience
- Leafy greens for micronutrient density
- Root vegetables for more substantial meals
Legumes
Lentils, chickpeas, and beans are among the most fibre-dense foods available. They also provide plant-based protein, making them particularly useful in meals focused on satiety and recovery.
Nuts and Seeds
Chia seeds, flaxseeds, and almonds offer a concentrated source of fibre and can be added easily to meals. Even small additions, such as a tablespoon of seeds in a breakfast or smoothie, can make a difference over time.
A Smarter Way to Think About Fibre
Fibre doesn’t need to be treated as a standalone goal. It works best as part of a balanced, well-structured approach to nutrition - one that supports how you feel day to day, not just how you perform in the odd moment.
For most people, that starts with whole foods. Building meals around plant variety, whole grains, and consistent habits. From there, the role of supplementation becomes more effective.
The Innermost approach reflects that balance. Products like The Greens Blend can help support daily plant intake and micronutrients, while products such as The Lean Protein fit alongside a diet that prioritises both protein and fibre, rather than one at the expense of the other.
Building a high fibre diet isn’t about adding or overhauling, instead It’s about making those small adjustments that bring more consistency to your routine. Over time, those shifts tend to have the biggest impact - not just on digestion, but on how your body feels, performs, and recovers.
References
- Renolds, A., Mann, J., Cummings, J., Winter, N., MDiet, E., Morenga, L. (2019). Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. The Lancet. 393 (10170), 434-445. Click here.
- NHS UK. How to get more fibre into your diet. Click here.
- Hullings, A., Sinha, R., Liao, L., Freedman, N., Graubard, B., Loftfield, E. (2020). Whole grain and dietary fiber intake and risk of colorectal cancer in the NIH-AARP Diet and Health Study cohort. The American Journal of Clinical Nutrition. 112 (3), 603-612. Click here.
- Threapleton, D., Greenwood, D., Evans, C., Cleghorn, C., Nykjaer, C., Woodhead, C., Cade, J., Gale, C., Burley, V. (2013). Dietary fibre intake and risk of cardiovascular disease: systematic review and meta-analysis. BMJ.347. Click here.
