Thirty Years On, the Mediterranean Diet Reaches for the Liver, Kidneys and Mind, but the Proof Thins Out Past the Heart
This narrative review marks three decades since the 1995 Mediterranean Diet Pyramid and asks whether the diet’s benefits extend beyond its established territory of cardiovascular disease, diabetes, cancer and cognitive decline. The authors survey the last ten years of work on fatty liver disease, chronic kidney disease and depression. They conclude that the evidence is growing in all three areas but admit that the wider potential “remains largely unexplored.” The paper presents no new data, uses no systematic search, and reports almost no effect sizes for the newer indications. Its firmest numbers are still the cardiovascular results from PREDIMED and CORDIOPREV.
The Mediterranean diet is the most studied eating pattern in history. A simple PubMed search returns 15,667 papers, against 2,205 for the DASH diet and 206 for the Nordic diet. Three researchers closely tied to that literature, including the lead investigator of the landmark PREDIMED trial, now ask what the diet can do beyond protecting the heart.
Their starting point is solid. PREDIMED randomized about 7,400 high-risk Spanish adults and found roughly 30 percent fewer major cardiovascular events in those given extra virgin olive oil or nuts on top of Mediterranean diet advice, compared with low-fat advice. CORDIOPREV later found a 26 percent lower risk of repeat events in people who already had heart disease. Few dietary patterns have randomized evidence on hard outcomes at all.
The review then moves to three newer areas. For fatty liver disease, now called MASLD and the most common chronic liver condition worldwide, several meta-analyses of randomized trials suggest the diet improves markers of disease severity. The authors argue its palatability makes it easier to sustain than restrictive diets. They also flag an unresolved problem: wine is part of the traditional pattern, yet alcohol is a liver toxin. A large trial called UNATI, running to 2028, is testing abstention against moderation within the diet.
For the kidneys, the picture is mixed. One trial in heart attack survivors found better preservation of kidney function. But a two-year Israeli weight-loss trial found the Mediterranean diet no better than low-fat or low-carbohydrate diets, and PREDIMED found no reduction in diabetic kidney disease after six years. The authors concede that few well-powered trials exist.
For depression, pooled observational studies link the highest adherence to a 33 percent lower risk of developing the condition. The randomized evidence is much weaker. PREDIMED’s depression results were, in the authors’ words, “basically null,” and a later trial in recovered patients was disrupted by the pandemic, showing gains only in quality-of-life scores.
The proposed mechanisms are familiar: olive oil phenols, fiber, unsaturated fats, potassium and magnesium acting on inflammation, oxidative stress, insulin sensitivity and gut microbes. The authors make one practical point here. Olive oil has only modest effects on cholesterol, so the phenol content of the oil matters, and cheap refined oil is not a substitute.
The review closes on cost and climate. Healthy diets remain more expensive than unhealthy ones, and climate change is already affecting olive, fruit and vegetable production.
The big idea is that one dietary pattern may act as a general chronic disease strategy. The evidence in this paper supports that for the heart and plausibly for the liver. For kidneys and mood it remains a hypothesis.
Actionable Insights
The strongest take-home message is cardiovascular. In PREDIMED, about 11 of every 1,000 people in the control group had a heart attack, stroke or cardiovascular death each year. In the olive oil and nut groups it was about 8. That is 3 fewer events per 1,000 people per year, a 30 percent relative drop but a small absolute one for any individual. For people with existing heart disease the payoff was larger: 17 percent had a repeat event over seven years on the Mediterranean diet versus 22 percent on low-fat, so about 1 in 20 avoided an event.
Practical steps supported by those trials:
- Use extra virgin olive oil as the main fat, around 4 tablespoons a day in PREDIMED. Choose high-phenol oils.
- Eat about 30 g of mixed nuts daily.
- Keep red meat, processed meat and junk food minimal.
- If you have fatty liver, the diet is a reasonable first-line choice, but skip the wine.
For depression, the 33 percent lower risk comes from observational studies and may reflect healthier people choosing better diets. For kidney protection, the diet has not beaten other sensible diets in trials. Treat both as possible bonuses.
Context and Source
- Full title: The Mediterranean pyramid: 30 years later, still relevant
- Institutions: University of Padova (Italy); IMDEA-Nutrition, ClĂnica Universidad de Navarra, University of Navarra and CIBERObn (Spain); Harvard T.H. Chan School of Public Health (USA)
- Journal: European Journal of Nutrition (Springer), Published online 24 September 2026.
- Impact evaluation: The impact score of this journal is 4.5, evaluated against a typical high-end range of 0–60+ for top general science and medical journals, therefore this is a Medium impact journal.