EvidenceCLimitedStudies in people with real weaknesses: small, short or conflicting trials, or observational studies only.
People who eat a Mediterranean-style diet more closely tend to live longer, but this comes from observational Studies that watch what happens to people rather than assigning a treatment. They can show links, not cause and effect. studies. Trials haven't shown the diet itself extends life.
Who it's for
Healthy adults wanting a heart-friendly eating pattern; life extension isn't proven.
What to expect
About 8 to 9% lower risk of death in observational data.
Watch out for
Nothing notable reported; trials found few and minor side effects.
Closer Mediterranean eating goes with lower risk of death
Each dot is the pooled risk of death from all causes for a two point higher diet score, with a line showing its 95% range.
← BetterWorse →
No difference
Meta-analysis, 20080.91 (0.89 to 0.94)Clear improvement
Meta-analysis, 20100.92 (0.9 to 0.94)Clear improvement
Meta-analysis, 20140.92 (0.91 to 0.93)Clear improvement
1
risk of death vs. lower adherence, 1 = same
Closer Mediterranean eating goes with lower risk of death
Result
Estimate
95% range
Reading
Meta-analysis, 2008
0.91
0.89 to 0.94
Clear improvement
Meta-analysis, 2010
0.92
0.9 to 0.94
Clear improvement
Meta-analysis, 2014
0.92
0.91 to 0.93
Clear improvement
Sources 1 BMJ, 2008; 2 Public Health Nutr, 2014; 3 Am J Clin Nutr, 2010
In a trial, the diet did not clearly change total deaths
Each dot is the effect on deaths or heart events in the PREDIMED trial compared with a low-fat diet, with a line showing its 95% range.
← BetterWorse →
No difference
Total deaths1 (0.81 to 1.24)No clear difference
Deaths from heart disease0.81 (0.5 to 1.32)No clear difference
Strokes0.6 (0.45 to 0.8)Clear improvement
0.50.751
risk vs. low-fat diet, 1 = same
In a trial, the diet did not clearly change total deaths
Reviews that pooled studies following people for 3 to 18 years linked a 2-point higher diet score to a 9% lower risk of death from any cause1Meta-analysis · 2008 · 574,299 peopleAdherence to Mediterranean diet and health status: meta-analysis.Greater adherence to a Mediterranean diet is associated with a significant improvement in health status, as seen by a significant reduction in overall mortality (9%), mortality from cardiovascular diseases (9%), incidence of or mortality from cancer (6%), and incidence of Parkinson's disease and Alzheimer's disease…BMJ and an 8% lower risk in a later update covering over 4 million people2Meta-analysis · 2014 · 412 peopleMediterranean diet and health status: an updated meta-analysis and a proposal for a literature-based adherence score.The Mediterranean diet was found to be a healthy dietary pattern in terms of morbidity and mortality. By using data from the cohort studies we proposed a literature-based adherence score that can represent an easy tool for the estimation of adherence to the Mediterranean diet also at the individual level.Public Health Nutr,3Meta-analysis · 2010Accruing evidence on benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis.This updated meta-analysis confirms, in a larger number of subjects and studies, the significant and consistent protection provided by adherence to the Mediterranean diet in relation to the occurrence of major chronic degenerative diseases.Am J Clin Nutr. These figures compare groups. The gain for one person depends on how high their risk was to begin with.
These are observational studies. They show an association and can't rule out that people who eat this way also live healthier in other ways.
The strongest test, a Cochrane review of 30 trials with 12,461 people, found low-quality evidence of little or no effect on total deaths in PREDIMED (7,747 people, 4.8 years)5Meta-analysis · 2019 · 12,461 peopleMediterranean-style diet for the primary and secondary prevention of cardiovascular disease.Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in…Cochrane Database Syst Rev. That result could be down to chance.
The same trial found fewer strokes: about 14 per 1,000 people versus 24 per 1,000 on a low-fat diet over 4.8 years5Meta-analysis · 2019 · 12,461 peopleMediterranean-style diet for the primary and secondary prevention of cardiovascular disease.Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in…Cochrane Database Syst Rev. Its authors note it wasn't big or long enough to judge death from any cause10Randomized trial · 2017The PREDIMED trial, Mediterranean diet and health outcomes: How strong is the evidence?The PREDIMED study was designed to overcome three major problems of previous nutritional research: a) residual confounding, addressed by using a randomized design; b) single-nutrient approaches, by randomizing an overall dietary pattern; and c) the limitations of assessing only intermediate risk markers, by using hard…Nutr Metab Cardiovasc Dis.
In two trials of people after a first heart attack, a Mediterranean-style diet was linked to fewer repeat heart events7Randomized trial · 1999Mediterranean diet, traditional risk factors, and the rate of cardiovascular complications after myocardial infarction: final report of the Lyon Diet Heart Study.The protective effect of the Mediterranean dietary pattern was maintained up to 4 years after the first infarction, confirming previous intermediate analyses. Major traditional risk factors, such as high blood cholesterol and blood pressure, were shown to be independent and joint predictors of recurrence, indicating…Circulation and fewer deaths: 8 versus 20 over about 27 months9Randomized trial · 1994 · 303 peopleMediterranean alpha-linolenic acid-rich diet in secondary prevention of coronary heart disease.02). An alpha-linolenic acid-rich Mediterranean diet seems to be more efficient than presently used diets in the secondary prevention of coronary events and death.Lancet. Both were single trials, and the first has been questioned for small size.
A review of 117 studies linked the closest adherence to a 13% lower risk of cancer death and a 25% lower risk of death among cancer survivors, though most comparisons were low or very low certainty4Meta-analysis · 2021 · 3,202,496 peopleAn updated systematic review and meta-analysis on adherence to mediterranean diet and risk of cancer.In conclusion, our results suggest that highest adherence to the MedDiet was related to lower risk of cancer mortality in the general population, and all-cause mortality among cancer survivors as well as colorectal, head and neck, respiratory, gastric, liver and bladder cancer risks. Moderate certainty of evidence…Eur J Nutr.
Key studies
Study
Who
What it found
Review of cohort studies Researchers follow a group of people over time without giving them a treatment. It can show links, not cause and effect., 20142Meta-analysis · 2014 · 412 peopleMediterranean diet and health status: an updated meta-analysis and a proposal for a literature-based adherence score.The Mediterranean diet was found to be a healthy dietary pattern in terms of morbidity and mortality. By using data from the cohort studies we proposed a literature-based adherence score that can represent an easy tool for the estimation of adherence to the Mediterranean diet also at the individual level.Public Health Nutr
Over 4 million adults
8% lower risk of death per 2-point score rise
Review of 30 trials, 20195Meta-analysis · 2019 · 12,461 peopleMediterranean-style diet for the primary and secondary prevention of cardiovascular disease.Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in…Cochrane Database Syst Rev
12,461 adults
Little or no effect on total deaths; fewer strokes
Trial, 19949Randomized trial · 1994 · 303 peopleMediterranean alpha-linolenic acid-rich diet in secondary prevention of coronary heart disease.02). An alpha-linolenic acid-rich Mediterranean diet seems to be more efficient than presently used diets in the secondary prevention of coronary events and death.Lancet
Heart attack survivors
8 deaths versus 20 over about 27 months
Review of 117 studies, 20214Meta-analysis · 2021 · 3,202,496 peopleAn updated systematic review and meta-analysis on adherence to mediterranean diet and risk of cancer.In conclusion, our results suggest that highest adherence to the MedDiet was related to lower risk of cancer mortality in the general population, and all-cause mortality among cancer survivors as well as colorectal, head and neck, respiratory, gastric, liver and bladder cancer risks. Moderate certainty of evidence…Eur J Nutr
3.2 million adults
Lower cancer death risk; mostly low certainty
Safety
Two trials reported side effects that were absent or minor5Meta-analysis · 2019 · 12,461 peopleMediterranean-style diet for the primary and secondary prevention of cardiovascular disease.Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in…Cochrane Database Syst Rev.
What we don't know
Whether the diet extends life in healthy people, since no trial was large and long enough to test total deaths.
Whether the benefit comes from the diet or from other habits of people who follow it.
Written by AI from the studies listed, without review by a clinician, and graded with the GRADE method. It can be wrong, so check the studies it cites. Education, not medical advice.