Smart Fibers: Glucomannan, Inulin, and the Future of Functional Nutrition

Last Update: 2 August, 2026 | 21:38

Fibre was once dismissed as roughage. Soluble, fermentable fibres such as glucomannan and inulin are now understood to affect metabolism, blood glucose, immune modulation, and the gut microbiome. This volume reviews the evidence.

Secrets of a Healthy Society

A few decades ago fibre was regarded as little more than bulk for the intestines. Soluble, fermentable fibres such as glucomannan and inulin are now understood to act on metabolism, blood glucose, immune function, and the gut microbiome. Prof. Seyed-Moayed Alavian reviews what the evidence actually supports.

Author

Prof. Seyed-Moayed Alavian

Publisher

Brieflands

Series

Secrets of a Healthy Society

Subject

Dietary fibre, prebiotics, and the gut microbiome

Audience

Clinicians, nutritionists, researchers, and general readers

Availability

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About this book

Health is no longer defined simply as the absence of disease. It means living deliberately — knowing what we put into our bodies and what role each component plays in the working of cells, tissues, and mind. Dietary fibre is among the least understood of those components: simple in appearance, complex and consequential in function.

Until relatively recently fibre was treated as a bulking agent and little more. Today, soluble and fermentable types — glucomannan and inulin among them — are recognised for their part in regulating metabolism, modulating immunity, influencing blood glucose, and maintaining the balance of gut bacteria.

This volume takes a scientific, evidence-based, and practical look at functional fibres: how glucomannan's water absorption and satiety effects relate to weight control and metabolic indicators, and how inulin acts as a prebiotic supporting beneficial gut bacteria, immune function, and digestive health.

The future of medicine is a preventive and nutrition-oriented future. Instead of treating diseases, we must move toward managing health — and this path begins with nutritional awareness.Prof. Seyed-Moayed Alavian — from the preface

What the book covers

Rethinking fibre

Why the old picture of fibre as mere roughage no longer holds.

Glucomannan

Water absorption, satiety, and the evidence on weight and metabolic indicators.

Inulin as a prebiotic

Supporting beneficial gut bacteria, and the downstream effects on immunity and digestion.

Metabolic regulation

How fermentable fibres influence blood glucose and metabolic health.

The gut microbiome

Microbial balance as a mechanism linking diet to whole-body health.

Science to the table

Translating research into choices that work in an ordinary household.

Note. This book is nutrition education, not individual medical advice. Concentrated fibre supplements are not risk-free: glucomannan in particular must be taken with adequate fluid, as it can cause choking or intestinal obstruction if it swells before reaching the stomach, and fermentable fibres can worsen symptoms in some digestive conditions. Discuss fibre supplements with a clinician or dietitian, especially if you take medication or have a gastrointestinal disorder.