What Is the Mediterranean Diet?
The Mediterranean diet is not a rigid plan but a traditional eating pattern from countries bordering the Mediterranean Sea — particularly Greece, southern Italy, and Spain in the 1960s, before westernisation. Its defining features are an abundance of plant foods, olive oil as the primary fat, moderate fish and poultry consumption, and low intake of red meat and processed foods.
What to Eat — and What to Avoid
- Eat abundantly: vegetables, fruits, legumes (beans, lentils, chickpeas), whole grains, nuts, seeds, herbs, and spices
- Primary fat: extra-virgin olive oil — 4+ tablespoons daily in the PREDIMED trial
- Eat regularly: fish and seafood (2+ times/week), especially oily fish rich in omega-3s
- Eat in moderation: eggs, dairy (mainly as yoghurt and cheese), and poultry
- Eat rarely: red and processed meat, butter, refined grains, added sugar, and ultra-processed foods
- Optional: red wine — 1 glass with meals (no more than 1–2/day); do not start drinking for health reasons
The Evidence: PREDIMED and Beyond
The PREDIMED trial — one of the most important nutrition studies ever conducted — randomised 7,447 high-risk Spanish adults to a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a low-fat control diet. After 5 years, the Mediterranean diet groups had a 30% lower rate of major cardiovascular events (heart attack, stroke, or cardiovascular death) compared with the low-fat group.
Beyond heart disease, meta-analyses show Mediterranean diet adherence is associated with:
- 30% lower risk of type 2 diabetes
- Slower cognitive decline and reduced dementia risk
- Lower rates of depression
- Reduced inflammation (lower CRP and IL-6)
- Lower all-cause mortality
Why It Works
The Mediterranean diet is high in monounsaturated fats (olive oil) and omega-3 fatty acids (oily fish), both of which reduce inflammation and improve lipid profiles. High fibre from legumes and whole grains supports a diverse gut microbiome. Polyphenols in olive oil, red wine, tomatoes, and berries have antioxidant and anti-inflammatory properties. There is no single "active ingredient" — the benefit comes from the overall dietary pattern.
How to Start
You don't need to overhaul your diet overnight. Practical steps:
- Switch from butter and seed oils to extra-virgin olive oil for cooking and dressings
- Have fish twice a week (salmon, sardines, mackerel, herring)
- Replace meat as a centrepiece with legumes or vegetables two to three nights per week
- Eat a handful of mixed nuts (walnuts, almonds) daily
- Base meals on vegetables, grains, and legumes; meat becomes a condiment rather than a main
- Finish meals with fruit instead of dessert