Fibre has spent decades with an image problem. For many of us, it still means roughage, bran cereal and keeping the bowels moving.
In this episode, we look at why that view is far too narrow.
We explore the evidence linking higher fibre intake with lower risks of cardiovascular disease, type 2 diabetes, colorectal cancer and premature death, and ask the obvious question: is fibre itself helping, or is it simply travelling with an otherwise healthy diet?
We also look at intervention studies showing that specific fibres such as psyllium and oat beta-glucan can lower LDL cholesterol, explain how fibre can affect cholesterol and blood sugar despite the fact that we don’t digest it, and unpack why “fibre” is really a family of substances with different physiological effects.
We also take a more sceptical look at the popular microbiome and short-chain-fatty-acid story, where the human evidence is less tidy than the headlines suggest.
Finally, we look at how much fibre most of us actually eat, why 25–30g/day may be better thought of as a minimum target than an optimum, and the simple first step we’d suggest before trying to change your diet: work out where you’re starting from.
