‍A quiet shortfall with big consequences

From media headlines to influencer advice, protein often takes the spotlight. Yet hiding in the shadows the nutrient that most of us under-consume is fibre. Public health bodies set adult targets around 25–38 grams per day, depending on sex and country. Actual intake? Consistently lower in the UK, the US, and across Europe, with only a small fraction of adults hitting the mark. (World Health Organization)

Rhiannon Lambert is a renowned UK Registered Nutritionist (RNutr), best-selling author, and founder of the acclaimed Rhitrition Clinic on Harley Street, London. Source: Rhiannon Lambert

What fibre does for you

There are two types of fibre, soluble and insoluble. According to large public-health reviews and clinical guidance fibre does more than just support healthy digestion; it also helps manage cholesterol, blood glucose, and feeds the gut microbiome. Always aim for a mix of sources, since soluble and insoluble fibres work in complementary ways. (World Health Organization)

How big is the shortfall?

  • UK: Recent analysis of the National Diet & Nutrition Survey (NDNS) indicates only about 4% of adults meet the 30 g/day recommendation. (Food Foundation)

  • US: Average adult intake lands around 15–16 g/day, far below the 25 g/day (women) and 38 g/day (men) Adequate Intake levels. (Economic Research Service)

  • Europe (overall): Most adults fall short of the 25 g/day benchmark; many national averages sit in the high teens to low twenties. (eufic.org)

These numbers align with the long-term pattern captured by national surveys. However, the WHO guidance encourages at least 25g/day of naturally occurring dietary fibre for adults. From this it is clear that there is a big shortfall.

(GOV.UK)

Why we’re missing fibre

It’s not one thing, it’s a pattern: refined carbohydrates displacing wholegrains, meals eaten away from home that tend to be lower in fibre, and a general underemphasis on legumes, nuts, seeds, and veg. US data show “at-home” foods have higher fibre density than many restaurant options, which nudges intake down when we rely on eating out. (Economic Research Service)

Closing the gap, one plate at a time

No hero foods required. Small, steady swaps add up:

  • Choose wholegrain versions of breads, cereals, and pasta.

  • Add one portion of pulses to a meal most days.

  • Keep a “default” snack of fruit, nuts, or roasted chickpeas.

  • Build “plants first” plates, then layer protein and healthy fats.

If you’re increasing fibre, go gradually and drink water to keep things comfortable. (Health)

Rhiannon Lambert is a renowned UK Registered Nutritionist (RNutr), best-selling author, and founder of the acclaimed Rhitrition Clinic on Harley Street, London. Source: Rhiannon Lambert

Author spotlight: Rhiannon Lambert and The Fibre Formula

Rhiannon Lambert is a UK Registered Nutritionist, Sunday Times bestselling author, and founder of the Harley Street clinic Rhitrition. She hosts the Food for Thought podcast and co-hosts The Wellness Scoop with Ella Mills. Her previous titles include The Science of Nutrition and The Science of Plant-Based Nutrition and The Unprocessed Plate. (Rhitrition)

Her forthcoming book, The Fibre Formula: Eat Your Way to Better Health Through the Power of Fibre, positions fibre as the overlooked cornerstone of everyday health, with practical strategies and recipes to help readers meet daily needs. According to the publisher’s announcement, the UK release is slated for March 2026 and the US release for June 2026, with a central claim that around 96% of people are deficient in fibre—a framing consistent with NDNS findings that only a small minority meet targets.

“We’ve never had a protein deficiency crisis in the UK, yet protein dominates our supermarket shelves and social feeds. Meanwhile, fibre… barely gets a mention,” Lambert notes in the announcement, underscoring the book’s goal of practical, no-gimmick ways to hit fibre goals.

Quick reference: daily fibre targets

Final thought

Fibre isn’t a trend, it’s infrastructure for health. The simplest path forward is to make high-fibre choices the default: wholegrains over refined, pulses most days, and plants in every meal. That steady approach, echoed by Lambert’s upcoming The Fibre Formula, is how most people can bridge the gap without fuss.