The water footprint is a measure of the volume of water that is polluted, evaporated, and consumed. The water footprint is examined in three groups: green, grey, and blue water footprint.

The blue water footprint refers to the amount of groundwater or surface water used to create a product.

The green water footprint refers to the amount of rainwater used to create a product.

The grey water footprint is the amount of fresh water required to eliminate pollutants resulting from the production of the product.

The use of water in food production is an important measure. Especially in the production of animal products, more water is needed compared to plant-based products. Diets heavy in meat and other animal foods have a higher water footprint compared to vegetarian diets. For example, the water footprint of beef is 20 times greater than that of grains. Approximately 15,000 liters of water are consumed for 1 kg of beef. (The amount of water required for production varies depending on the production system and the feed used for the animal.)

The ranking of water footprints from least to most among vegetables is as follows:

Tuber crops, fruits, grains, oilseeds, legumes, nuts.

The ranking of water footprints from least to most among animal-based foods is:

Milk, eggs, chicken meat, butter, cheese, goat meat, sheep meat, beef.

When evaluating the water footprint in terms of protein for foods, 100 times more water is used in the production of 1 kg of animal protein compared to 1 kg of grain protein.

When looking at the greenhouse gas emissions resulting from the cultivation and production of various foods, it is found that, just like the water footprint, animal protein sources (beef, sheep meat, some cheeses) generate greenhouse gas emissions. Plant protein sources and grains have low greenhouse gas emissions.

Therefore, the sustainability of dietary models that reduce the consumption of meat and meat products while increasing the consumption of plant protein sources is a crucial issue for reducing water footprints and greenhouse gas emissions.

Considering the depletion of resources worldwide and environmental pollution, it is essential to choose food and dietary models that have less impact on the environment instead of those that have significant effects.

To protect universal health, all resources on Earth should be used carefully, and harm to the environment should be avoided. It is necessary to reduce waste in production, food waste, food losses (losses occurring during the distribution of edible parts of foods), and economic losses. These losses cause waste of soil, energy, and water while also leading to unnecessary greenhouse gas emissions. Additionally, the amount of water consumed in the food production process should also be reduced.

The main principle of sustainable nutrition is to consume seasonal vegetables and fruits and to allocate more space for plant-based proteins in the diet. The water footprint and greenhouse gas emissions should be low, and it should also enable food diversity through easy accessibility.

Mediterranean-style nutrition has a healthy and balanced fat pattern, low glycemic index, and high fiber and antioxidant content. The Mediterranean diet is an important dietary model as it provides the necessary nutrients and elements for a healthy and quality life.

For a healthy adult, the Mediterranean diet recommends 8 servings of grains, 2-3 servings of vegetables, 4-6 servings of fruits, 2 servings of low-fat dairy products, at least 2 servings of fish per week (the diet of the fish has a significant impact on the environmental efficiency of fish consumption, and it is anticipated that difficulties may arise in finding fish sources in the future, so alternative sources for omega-3 fatty acids should be sought), less than 2 servings of red meat, and a predominant consumption of olive oil.

The foundation of this dietary model is the inclusion of low-impact food groups like vegetables, fruits, and grains, and the limited consumption of animal products, which distinguishes the Mediterranean diet from other dietary models.

Population growth and the corresponding decrease in water, soil, and food resources worldwide can become a significant problem for the future. Therefore, action should be taken to protect our resources.

The Mediterranean diet is a sustainable dietary model due to its positive health effects and its low water footprint and greenhouse gas emissions. The public should be educated about and encouraged to adopt the Mediterranean diet.