Carbohydrate quality and human health — dietary fibre and whole grains
In plain English
Commissioned by the WHO to settle how much dietary fibre actually matters, this synthesis pooled 185 prospective studies (covering roughly 135 million person-years) and 58 clinical trials. People eating the most fibre had 15-30% lower all-cause and cardiovascular mortality, and 16-24% lower incidence of coronary heart disease, stroke, type 2 diabetes and colorectal cancer than those eating the least. The protective sweet spot was 25-29 g of fibre a day, with more conferring additional benefit — most adults eat far less.
Why it matters
Eating 25-29 g+ of fibre daily cut mortality and the big four chronic diseases by 15-30%.
Informs: Heart Disease·Stroke·Cancer·Diabetes
Provenance
- Design
- Meta-analysis
- Sample size (n)
- 4,635
- Follow-up
- 40 years
- Peer-reviewed
- Yes
- Replications
- 3
- Funding
- Public / academic
- Funders
- Health Research Council of New Zealand, World Health Organization, Riddet Institute
- Institutions
- University of Otago, University of Dundee
decades.plus score
A transparent 0–100 weighted sum across six components. Higher scores reflect bigger, cleaner, more replicated work.
Caveats
The trials underpinning the causal claim are smaller and shorter than the observational base; fibre intake also tracks with overall diet quality, so part of the benefit reflects whole dietary patterns, not fibre in isolation. Evidence was rated moderate for fibre, lower for glycaemic index.
