Public Health Nutrition Editorial Highlight: The Mediterranean diet, an environmentally friendly option: evidence from the Seguimiento Universidad de Navarra (SUN) cohort‘ Authors: Ujué Fresán, Miguel-Angel Martínez-Gonzalez, Joan Sabaté and Maira Bes-Rastrollo discuss their research below.

The Mediterranean diet (MedDiet) is characterized by the consumption of high amounts of vegetables, cereals (mostly unrefined), legumes, nuts, olive oil as the main source of fats, moderate intake of fish and dairy products, low quantities of meat and meat products, and an optional moderate wine consumption mainly during meals. How food is produced and consumed has consequences for ecosystems, as resources use or greenhouse gas (GHG) emissions among others. The impact on the environment differs among food items; for example, vegetable-based foods have lower environmental impact compared to foods coming from animals.

Sustainable diets have been defined as “those diets with low environmental impacts which contribute to food and nutrition security and to healthy life for present and future generations. Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy; while optimizing natural and human resources“. Because of that, the MedDiet was proposed as a sustainable dietary model, due to its nutritional, environmental, economic and socio-cultural dimensions.

However, it has not been assessed using real data from a sample of a Mediterranean free-living people. Thus, our objective was to evaluate the impact on resources (land, water and energy) consumption and GHG emissions of a better adherence to the MedDiet, using the index proposed by Trichopoulou et al. (10), in 20,363 participants of the Mediterranean Spanish cohort (SUN project). We analyzed the dietary pattern of participants through a validated food-frequency questionnaire, and we observed that a better adherence to MedDiet was associated with lower land use (-0.71 (95% CI -0.76, -0.66) m2/day), water consumption (-58.88 (95% CI -90.12, -27.64) L/day), energy consumption (-0.86 (95% CI -1.01, -0.70) MJ/day) and GHG emission (-0.73 (95% CI -0.78, -0.69) Kg CO2e /day). It should be highlighted that the amount of animal-based food in the diet, particularly meat and dairy products, were the most significant contributors to the harms for the environment in all analyzed outcomes, and the most contributive item of all of them was by far beef consumption.

Global dietary patterns have changed in the last years, and the population tends more and more to consume foods with negative impacts for their health and the environment, such as red meats or processed foods (11). Because of that, nutritionist giving dietary advice may take into account not only the healthiness of a diet but also its environmental impact, and enhancing adherence to a MedDiet is likely to be an important target to be fostered in our society. Our results support the sustainable great idea in nutrition: what is good for your health, it is also good for your planet. Nutritionist have another good reason to promote healthy dietary patterns based on plant-based foods such as the Mediterranean diet.

The full article  The Mediterranean diet, an environmentally friendly option: evidence from the Seguimiento Universidad de Navarra (SUN) cohort‘  in Public Health Nutrition is available to download for free until 23rd March 2018.