One of nutrition science's most cited trials — including the correction that's part of its honest story.
PREDIMED (Prevención con Dieta Mediterránea) is one of the largest and most cited randomised trials in nutrition science — following thousands of participants at high cardiovascular risk across Spain, comparing a Mediterranean diet (supplemented with either extra-virgin olive oil or nuts) against a lower-fat control diet.
The Mediterranean diet groups showed a meaningfully lower rate of major cardiovascular events (heart attack, stroke, cardiovascular death) compared to the control group — a genuinely significant finding for a dietary intervention trial, which are notoriously difficult to run well.
The original PREDIMED trial faced a methodological correction in 2018 over randomisation issues at some study sites — the researchers reanalysed the data and the core findings held up, but it's a genuine example of nutrition science self-correcting, worth knowing rather than glossing over.
PREDIMED is part of the evidence base our Mediterranean diet comparison and general Food signal draw on — it's one of the more rigorously tested dietary patterns referenced anywhere on this site.