Hanna Geissler, right, reports on s-called fibremaxxing. (Image: Getty / Express)
How many grams of fibre are there in an apple? How about a portion of broccoli or a slice of white bread? If your answer was, “I have no idea”, then you’re not alone. Research suggests most of us have no idea how much fibre we should be consuming or where to find it. A staggering 96% of adults and teenagers do not meet the recommended daily fibre intake (30g and 25g, respectively), according to the latest UK National Diet and Nutrition Survey, which is used by governments to monitor our nutrition.
This may be about to change – social media is suddenly rife with posts about “fibremaxxing”, a wellness trend that is all about increasing your fibre intake and eating more whole plant foods. And in a recent report, British retailer M&S identified fibremaxxing as one of the five food health trends set to dominate 2026.
However, experts have warned that reaching for fibre-rich foods without doing your research could have unpleasant consequences. We’ve asked nutritionists and dieticians to give us the low-down on how to establish a full-fibre connection, the right way.
Fibre is on of the unsung heroes of our diets (Image: Getty Images)
What is fibre?
Fibre is a type of carbohydrate found in plant-based foods such as fruits, vegetables, grains, pulses and seeds. Unlike other nutrients, it is not digested but helps to keep the digestive system healthy and can prevent constipation, among other benefits. Louisa Brunt, a senior nutritionist at M&S Food, describes fibre as “a hidden hero in our diets”. She says: “Internally at M&S we say that fibre is sexy! Found in plant-based foods, it’s so important to our nutrition as it helps keep our digestive system running smoothly and plays an important role in supporting overall health; supporting gut health, helps us stay fuller for longer, stabilises blood sugar levels and supports heart health by reducing LDL (bad) cholesterol.”
High-fibre diets have been linked to a lower risk of heart disease, stroke, type 2 diabetes, and bowel cancer. There are two types of fibre: soluble and insoluble. Soluble fibre, found in fruit, vegetables and pulses, dissolves in water to form a gel, aiding in lowering cholesterol and managing blood sugar. Insoluble fibre, found in the outer shell of seeds, grains, fruits and vegetables, does not dissolve, adding bulk to stool to prevent constipation.
Soluble fibre can also help feed beneficial gut bacteria such as lactobacillus and bifidobacteria, with the fibre acting as a prebiotic to encourage the flourishing of a healthy microbiome. Fibre can also be taken in pill form or powder as a laxative. Some people with certain health conditions may need to restrict their fibre intake, so always follow your doctor’s advice.
How much fibre do we need?
Adults in the UK are recommended to eat 30g of fibre a day but research has found most are only managing around 16.4g — just over half. Only 4% were meeting the recommendation, with cereals the biggest source of fibre for all age groups, followed by vegetables.
For children, recommendations vary by age group: 12.5g for those aged 18 months to three years, 14.5g for those aged four to 10 years, and 15.4g for those aged 11 to 18 years. Around 22% of children aged 18 months to three years were meeting the target, along with 14% of those aged four to 10, and 4% of teenagers aged 11 to 18.
A recent survey of 2,000 adults by cereal brand Weetabix found 49% felt confident in their fibre knowledge and 52% believed they were hitting targets. However, only 8% correctly identified the recommended 30g per day intake. Most vastly underestimated it, with an average estimate of 22.9g.
Sian Porter, a consultant dietitian to the Weetabix Food Company, says: “The easiest ways to increase fibre are to add fibre-rich ingredients to meals and make simple additions or swaps, such as adding fruit to your cereal, sprinkling nuts or seeds on yoghurt or soup, choosing wholegrains over white rice or pasta, keeping edible skins on fruit and veg, and swapping snacks like crisps for nuts or meat for beans and lentils. Build these changes gradually and remember to drink plenty of fluids.”
M&S Food nutritionist Louisa Brunt says high-fibre helps keep our digestive system running smoothly (Image: M&S)
What is fibremaxxing?
This viral social media trend has led to an explosion of videos and posts about how to boost your fibre intake. It is similar to the fitness trend of “protein-maxxing”, but focuses heavily on whole plant foods rather than relying on supplements. Fibre fanatics and influencers have shared their recipes for dense bean salads packed with ingredients such as chickpeas, lentils and kidney beans, or taken on the challenge of eating more than 30 different plants in a single week to diversify their microbiome. Some have even dubbed it a “natural GLP-1” weight loss aid.
M&S customer surveys have also shown people are becoming more aware of fibre and recognising its importance in our everyday diets. Louisa says: “Thanks to social media trends, fibre is being pushed into the spotlight, becoming the next high protein with growing customer demand and more customers are seeking high fibre options in their everyday diets. In a recent Bounce Insights customer survey, 92% of our customers indicated wanting support to increase their fibre intake.”
What can go wrong?
As with almost any food trend, taking it to the extreme can be dangerous. Gastrointestinal experts have warned of nasty side effects for those who increase their fibre intake too rapidly or far exceed daily recommendations. Kirsten Jackson, a gut health specialist known as The IBS Dietitian said: “Most of the fibre people are consuming is from low quality sources such as highly processed wheat flour in a pizza. So yes, an increase in fibre is good and needed but I would not advise ‘fibremaxxing’, which is a trend that encourages people to eat as much fibre as possible.
“For the average person, going from zero to 100 will cause a range of GI discomforts such as bloating, loose stools, abdominal pain and even constipation in some. And for the one in 10 people who have IBS, increasing fibre intake without any strategy could quite quickly cause a whole host of GI symptoms as many fibre sources are high in FODMAPs [carbohydrates that are poorly absorbed in the gut].”
Louisa’s top foods to increase your fibre intake
M&S new nutrient range is packed with fibre, vitamins, minerals… and flavour (Image: M&S)
Wholegrains — brown and wholegrain varieties of rice, pasta, bread and other grains are richer sources of fibre than white varieties. This is because wholegrains retain the entire grain, including the germ, endosperm and bran layers.
Beans and pulses — a plant-based fibre and a source of protein, beans and pulses contain on average 2.5 times more fibre than two slices of white bread.
Nuts and seeds — contain both soluble and insoluble fibre, great to sprinkle on soups, salads or breakfast.
M&S Nutrient Dense Super Seeded Oaty Bread — packed with sunflower seeds, linseed, oats and pumpkin seeds, 13g fibre per portion, great toasted and loaded with nut butter and fresh raspberries.
M&S Nutrient Dense H5O shot – 4g of fibre in one easy shot! The fibre comes from baobab and Jerusalem artichoke, and is high in iodine from high-quality sea moss sourced from the cold Atlantic off the coast of Ireland.
Louisa adds: “Aim for variety — the important thing about fibre is getting lots of different types of fibre from different food sources. Think beta-glucans from oats, oligosaccharides from fruits and wheat bran from pasta and bread.”
M&S Nutrient Dense drink (Image: M&S nutrient shot drink)
How can you safely increase your fibre intake?
Kirsten advises upping your fibre gradually. “The gut is a muscle so you need to train like this — slowly increasing,” she explains. Louisa agrees: “We want to help people get more fibre in their diets but not go from 3g a day straight to 30g!” You could start by learning a little about how much fibre is in the food you eat. The British Nutrition Foundation’s website provides advice about 10 of the best sources of fibre, including peas, potatoes with skin on and dried fruits. Other reliable sources of information include the NHS website and the charity Guts UK’s website.
Once you have an idea of how much fibre you currently consume, you could begin increasing your intake by around 5g every few days, giving your gut microbiome time to adjust. You may also need to increase your intake of fluids and water to help fibre move smoothly through your digestive system.
“Start small and build up,” Louisa adds. “A good tip is to stagger your fibre intake across meals and snacks throughout the day, be careful not to overload your digestive system with fibre as this can be uncomfortable. Your gut is like a muscle which you need to train. For example, sprinkling some chia seeds on your breakfast, or opting for wholemeal bread at lunchtime instead of white are some easy quick wins to adding in more fibre.”
M&S has created a new Nutrient Dense range in collaboration with the British Nutrition Foundation, with high-fibre products that also contain at least one of 10 vital nutrients including vitamin D, iron and folate. For example, eating two slices of the brand’s Nutrient Dense Super Seeded Oaty Bread with peanut butter would help you start the day with 15g of fibre.
Sainsbury’s has also launched a new “Small but Mighty” range of products under 350 calories and packed with protein and fibre.
Examples of high-fibre meals include porridge topped with nuts, seeds and fruit; lentil curry with brown rice; and wholegrain pasta with pesto and vegetables. If you have a limited budget, frozen or canned vegetables or canned mixed beans can help increase the variety of fibre sources in your diet.
This story originally appeared on Express.co.uk
