Water is an increasingly scarce resource subject to escalating demand from different sectors/ users/interests. Climate change and increasing rainfall variability and a speeding up of evapotranspiration compound water challenges, e.g. related to food production.
Food and nutrition security and improved livelihoods of farmers, who depend on large volumes of water to produce the food, entails three efforts: (i) enhanced water productivity (more crop per irrigation and rain water drop); (ii) to ensure that as much as feasible of the agricultural production is secured for farmers’ own consumption (food insecurity is widespread among hundreds of millions of small producers) and consumers, i.e. a more efficient food supply chain; (iii) to stimulate the demand and intake of food with lower water demand in relation to its nutritional value.
Sustainable diets are 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 (FAO, 2010).
During the last few decades, laudable progress has been made in terms of increasing agricultural/food production, totally, and on a per capita basis. Yields have increased and water productivity, ‘more crop per drop’, has improved. Little attention has, however, been devoted to what happens with the food that is produced, how much of it is lost and wasted in the supply chain and how much is actually eaten or beneficially used in other ways. Figures are uncertain, but according to many observers between 30% and 50% of agricultural production are lost or wasted.
Post harvest losses and waste of food is commensurable with a waste of the water, as well as other natural resources that were used in production. Moreover, they imply lost opportunities for farmers. Generally, a low efficiency in the food supply chain incurs various costs and impedes healthy and sustainable diets per drop of water.
Socioeconomic and political circumstances play an important role in production, access and how the available food is used. As a result of a very uneven income distribution and depending upon political contexts, access to the food available is far from equitable. Overeating has become much more prevalent than undernourishment. Moreover, it is relevant to mention that about 35 - 40% of the grain produced is converted to feed.
With increasing water scarcity and with high rates of undernourishment, overeating and conversions, it makes sense to scrutinize how efficient and productive water is used not only in production but also the link to sustainable diets. High efficiency in production needs to be combined with a high efficiency in the supply chain. Pre-and post-harvest losses need be reduced through cost-effective efforts. Processing and marketing, especially outside local markets require increased attention. In addition, with increasing disposable income among large segments of the world’s population, consumers’ attitudes and behaviour is a strong driver in the use of water and other resources.
Socioeconomic changes are most obviously demonstrated in conjunction with a massive urbanization. Growing distance between producers and consumers, physically and mentally means new demands on food supply systems. Similarly, with a larger share of food in the diets that is vulnerable to degradation, there is an obvious need to ensure supply chain efficiency.
Many of the components in the diet that are on the increase are high in energy use as well as water intensive (animal food items). Diets that are high in energy use but low in diversity contribute to obesity and chronic diseases, which particularly affect poor people in developing countries. Recent trends show an escalation in these problems, indicating an urgent need for strategies to advance sustainable diets with lower impact on water resources and that exert minimal pressure on the environment.
Actions to achieve target 8 will include coordinated efforts from many actors. At the local level, it will be essential to invest in post-harvest technologies and associated institutional arrangements. Better market contacts presume involvement of food industry and agents that are dealing with distribution to/from wholesale, retail and food outlets. Finally, consumer organizations, in cooperation with food industries have a great responsibility to promote sustainable diets and reduction in the waste of food.
A move towards sustainable diets will have multiple benefits for public health and environmental sustainability, with synergies felt across a number of sectors. The development of guidelines on sustainable diets should counsel the need to reduce the intake of highly processed energy-dense foods with high water demand.
As a basis for coordinated, acceptable and effective efforts by key actors in the supply chain, it will be important to:
- produce reliable empirical information about the level of losses and waste in different societies (industrial and developing, urban and rural) and how they vary over time (the magnitude of post harvest losses seem vary between the ‘fat’ and the ‘lean’ years; when farmers produce a bumper harvest they do not have the capacity to take care of the ‘surplus’ and they do not reach out to the national/international markets, i.e. losses may be higher after good seasons);
- make calculations about water requirements for sustainable diets;
- make calculations about how much water can be potentially saved from current situation;
- assessment the procurement of nutrients in different sustainable diets in term of cost in water.
Next steps could include an analysis of who does what, i.e. what can farmers and consumers do (what is their interest); what can official national and local agencies do; what can international organizations do; what can the corporate sector do; what can educational/communication experts do, etc.
Finally, cost benefit estimates are valuable for motivating policy interventions, investments and not least, changes in perceptions/paradigm and human behaviour