The Lancet, 2019 · Series of systematic reviews & meta-analyses
Comparing people who ate the most dietary fibre with those who ate the least, observational studies found 15–30% lower rates of death from all causes and from cardiovascular disease, and of coronary heart disease, stroke, type 2 diabetes and colorectal cancer, with the greatest benefit at 25–29 g a day. Trials showed lower body weight, blood pressure and cholesterol with more fibre.
Always read the original paper for context — effect sizes, study populations and funding sources matter.
