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The water diet

Development Policy18 Mar 2013Eva van der Zand

The ‘water diet’ implies  the challenge to make people aware that, in order to solve water issues, it is necessary to create a habit of sustainable food consumption.

The name “water diet” suggests that you should consume as much water as possible. But the opposite is true. This term is used to make people aware of the most essential problem regarding wasting water: “eating water”. Globally, we ‘eat’ an average of 3,496 liters of water every day. Eating water sounds strange but should be seen as an indirect way of eating, and can be used to acquire a broader understanding of water consumption. Everyone can be part of this water diet solution.

The challenge is to make people aware that, in order to solve water issues, it is necessary to create a habit of sustainable food consumption. Most people think that we use most water for domestic consumption. But this is only the visible part of the water used by households, and includes drinking, cooking, washing (around 137 liters every day). Of this, we use 35% for bathing and showering, 30% to flush the toilet, 20% for the laundry, 10% for cooking & drinking, and 5% for cleaning. There are, however, two other main uses for water, which are invisible.

Firstly, water used to produce the industrial goods we consume every day, such as paper, cotton and clothes (around 167 liters per day) and, secondly, water used to produce food, which amounts to 3,496 liters per day. This means that 92% of the water we use is invisible. Hidden in our food.

Professor Tony Allan can be seen as a pioneer in developing the key concepts that have improved the understanding and dialogue on water consumption globally. Professor Allan developed the concept of virtual water in 1993. Virtual water is the hidden flow of water when food or other commodities are traded from one place to another. By measuring how water is embedded in the production and trade of food and consumer products, the amount of virtual water in a product may be calculated. The concept of virtual water trade refers to the exchange of goods and services. For example, when a country imports one ton of wheat instead of producing it domestically, it is saving about 1,300 cubic meters of indigenous water consumption. Figures on the amount of virtual water in goods can indicate which nations consume the most. For example, US citizens consume 6,800 liters of virtual water a day per capita, while a person in China only consumes a third of that. Professor Allan also pioneered the ‘problem shed’ concept, emphasizing that the most serious threats to water can be remedied outside the water sector. Virtual water has had a major impact on global trade policy and research especially in water-scarce regions. It has also opened doors to more productive water use. The lesson that virtual water teaches us is that water and food security can be enhanced when water-intensive commodities are traded from places where their production is viable.

The amount of meat in our diet is crucial. The average daily water consumption of a meat eating person is 5,000 liters per day. For a vegetarian, it is 2,500 liters. The type of meat is also important. Meat from animals that are fed with grass (e.g. sheep) is more sustainable, since the land often cannot be used for food production for people. Moreover, we waste almost a third of all food produced (thereby wasting the water that was necessary to produce it). This is a crucial problem. Fruit and vegetables are more water-friendly than other food products.

In conclusion, most of the water we use (92%) is used in food production. Farmer’s water management should be high on the global agenda, together with reducing food loss and food waste. But the good news is that each one of us can also make the world a little more water secure. In addition to beef, bottled water is a big issue. Globally, this is a US$ 46 billion industry. As far as the production of soda drinks is concerned, some studies report that it takes up to 9 liters of water to produce one liter of Coke, often using water from dry areas in developing countries. This is, of course, information that such a company would rather not share. While 1/3 of the water is used to make the actual product, 2/3 of the water is used to clean the equipment and bottles needed to produce it. An unworldly amount of water is wasted by soda companies annually.

Part of the answer lies in our shopping baskets. We can eat ourselves out of this problem. Together, we can cooperate to reduce our virtual water consumption, and create a cultural change towards less wasteful habits. The past decade has seen astounding quantum leaps in popular attitudes towards recycling and energy use. Why not water? It is every bit as urgent. Count me in for a sustainable water diet.