Back to blog Home
Nutrition

Olive Oil and Your Heart: The Largest Randomised Dietary Trial in History Gives a Number

9 August 2026·6 min read
Sources of this article were verified3 scientific references with direct, checkable links

Olive oil is present in our kitchen, but most of us use it as a flavouring rather than a foundation. The evidence suggests the difference between the two may be a difference in lifespan.

The trial

PREDIMED — the largest randomised controlled trial of a dietary pattern in the history of cardiovascular prevention — enrolled 7,447 adults at high cardiovascular risk in Spain, randomised to: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control low-fat diet[1].

The result

After a median follow-up of 4.8 years, the extra-virgin olive oil arm showed a 31% relative reduction in heart attacks, strokes and cardiovascular deaths compared with the control diet[2]. In an analysis within the same study, each additional 10 grams a day of extra-virgin olive oil was associated with a 10% lower cardiovascular disease risk and 7% lower mortality[3].

7,447participants in
the trial
−31%risk of heart attack, stroke
and cardiovascular death
−10% per 10gwith roughly each additional
daily spoonful

A note of scientific honesty

The 2018 version published in NEJM is a republication and re-analysis of the original 2013 trial following a methodological review of randomisation at some sites[1],[2] — and the results remained consistent after correction. We mention this because transparency is part of sourcing.

How to apply it in our kitchen

🫒 Bottom line: Don't wait for a complete "Mediterranean diet" — start with a bottle of extra-virgin olive oil on your table, because that alone is what the largest trial in the field tested.

Scientific references

  1. Estruch R et al. — Primary prevention of cardiovascular disease with a Mediterranean diet supplemented with extra-virgin olive oil or nuts (NEJM 2018) — https://www.nejm.org/doi/full/10.1056/NEJMoa1800389
  2. PubMed abstract — the PREDIMED trial (2018) — https://pubmed.ncbi.nlm.nih.gov/29897866/
  3. Olive oil intake and risk of cardiovascular disease and mortality in the PREDIMED study — https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030221/

Snap your meal — we handle the rest

The first calorie app that knows kabsa, muhammar and jareesh by name — with 3D portion estimation and an Arabic-speaking coach.

Reserve your spot in the first batch 🚀
Back to all articles

Medical & legal disclaimer: Content on the FitCal blog is general education and awareness. It is not medical advice, a diagnosis, or a treatment plan, and it does not replace consulting a licensed healthcare practitioner who knows your case. Do not start or stop any medication, supplement, diet or training programme based on what you read here. Any mention of a drug, supplement or product is educational reporting of the scientific literature — not an advertisement or endorsement — and any doses cited are those used in the studies, not personal recommendations. Every figure is sourced at the bottom of each article so you can verify it yourself; if you spot an error, email us at fitcal@verokron.com and we will review and correct it. In Saudi Arabia, for health advice call 937; in an emergency call 997.