GLOSSARY

Viscous Fiber increases viscosity under suitable conditions and may form a gel. 'Viscous' refers to physical flow behaviour; mouthfeel alone cannot establish its physiological effect.

Solubility, viscosity and fermentability are separate properties. Inulin can be soluble, low-viscosity and readily fermented; psyllium forms gels but is generally less fermented. Two ingredients described as soluble fibre therefore need not produce the same intestinal consistency, gas production or post-meal response.

At suitable doses and in suitable forms, gel-forming fibre can change digestive contents' consistency and reduce the glucose response to some meals. Molecular weight, processing and actual inclusion matter. Not every soluble fibre, or tiny added amount, reproduces the effect observed with a specifically studied product.

Dietary fibre comprises components resistant to small-intestinal digestion and absorption, with definitions and analytical methods differing between authorities. Some definitions admit isolated or manufactured carbohydrates when beneficial physiological effects are demonstrated. Being non-digestible alone does not automatically qualify an ingredient as declared fibre in every labelling framework.

Oat and barley beta-glucans differ in linkage and structure from some yeast or fungal beta-glucans. Source, amount and product characteristics must be identified before transferring an effect. Research on cereal fibre and glucose or cholesterol does not establish immunity or performance claims for every supplement sharing the name.

Plant foods usually contain mixtures of fibre types. Oats are not only beta-glucan and wheat bran is not only cellulose; amounts change with variety and processing. A food name does not quantify every fraction, and findings for a purified fibre cannot simply be assigned in full to that food.

Fibre and plant foods contribute to overall diet quality, but choices can change temporarily around competition. An athlete prone to digestive discomfort may choose a lower-fibre meal before intense exercise and eat higher-fibre foods at another time. Adjusting timing differs from excluding a food group in the long term.