Global food waste must be addressed to feed growing world population

January 10, 2013


Up to fifty per cent of all food produced worldwide goes to waste, according to a new report by the Institution of Mechanical Engineers (UK) highlighting a crucial issue to be overcome if the increasing demands for food over coming decades are to be sustainably met. 


Credit: IMecheE

Feeding the 9 billion: the tragedy of food waste

Global Food: Waste Not, Want Not published today by the Institution of Mechanical Engineers (IMechE) examines the tragedy of global food waste, particularly given the increasing pressures humanity faces to produce more food due to changing consumer preferences and the world's population being expected to reach 9.3 billion by the middle of this century, up from today’s 7 billion. By mid-century a 70% increase in demand for agricultural production will have emerged, the report states.

By the end of the century there could be an extra three billion mouths to feed, a period in which substantial changes are anticipated in the wealth, calorific intake and dietary preferences of people in developing countries, at the same time as changing demographic trends in developed countries will have implications for food production and security.

Such a projection presents mankind with wide ranging social, economic, environmental and political issues that need to be addressed today to ensure a sustainable future for all. One key issue is how to produce more food in a world of finite resources.

Today, we produce about four billion metric tonnes of food per annum. Yet due to poor practices in harvesting, storage and transportation, as well as market and consumer wastage, it is estimated that 30–50% (or 1.2–2 billion tonnes) of all food produced never reaches a human stomach.

Furthermore, this figure does not reflect the fact that large amounts of land, energy, fertilisers and water have also been lost in the production of foodstuffs which simply end up as waste. This level of wastage is a tragedy that cannot continue if we are to overcome increasing pressures on land, water and energy usage and succeed in the challenge of sustainably meeting our future food demands.

In less-developed countries, such as those of sub-Saharan Africa and South-East Asia, wastage tends to occur primarily at the farmer-producer end of the supply chain. Inefficient harvesting, inadequate local transportation and poor infrastructure mean that produce is frequently handled inappropriately and stored under unsuitable farm site conditions.

As the development level of a country increases, so the food loss problem generally moves further up the supply chain with deficiencies in regional and national infrastructure having the largest impact. 

In mature, fully developed countries such as the UK, more-efficient farming practices and better transport, storage and processing facilities ensure that a larger proportion of the food produced reaches markets and consumers. However, characteristics associated with modern consumer culture mean produce is often wasted through retail and customer behaviour.

Major supermarkets, in meeting consumer expectations, will often reject entire crops of perfectly edible fruit and vegetables at the farm because they do not meet exacting marketing standards for their physical characteristics, such as size and appearance. Globally, retailers generate 1.6 million tonnes of food waste annually in this way.

Of the produce that does appear in the supermarket, commonly used sales promotions frequently encourage customers to purchase excessive quantities which, in the case of perishable foodstuffs, inevitably generates wastage in the home. Overall between 30% and 50% of what has been bought in developed countries is thrown away by the purchaser.

Recommendations for addressing food waste

Rising population combined with improved nutrition standards and shifting dietary preferences will exert pressure for increases in global food supply, with increasing pressure on finite resources of land, energy and water. Yet the report highlights that engineers, scientists and agriculturalists do have the knowledge, tools and systems that will assist in achieving productivity increases and states that there is the potential to provide 60–100% more food by simply eliminating losses, while simultaneously freeing up land, energy and water resources for other uses. 

PSN comment and calls for investment in family planning

Population and Sustainability Network welcomes the report by the Institute of Mechanical Engineering that sets out a number of important recommendations for how food waste must be overcome in order to help to sustainably meet the increasing demands for food over coming decades associated with changing consumer preferences and world population growth.

The growth in the world’s population that is projected to take place over the coming decades will present a great range of developmental challenges, including for food security and environmental sustainability. Governments should consider and implement as necessary the ways highlighted by the report to addressing food waste, which must  play a role in helping meet the challenges of ensuring food security for the 9 billion world population projected before 2050, which may exceed 10 billion by the end of the century.

Developed countries must take drastic measures to overcome the considerable waste at the market and consumer end of the food chain due to retail and customer behaviour. Developing countries must be supported to develop more efficient harvesting and local transport networks to address the wastage occurring at the farmer-producer end of the supply chain. These measures  help to achieve food security and also advance environmental sustainability, given the wasteful use of resources and unnecessary pressures on the environment associated the production of foodstuffs which only go to waste.

Overlooked by the report, we also emphasise that advancement of sexual and reproductive health and rights, including access to family planning, offers opportunities to reduce population growth before the world’s population reaches the projected level assumed in the report, which notably is not based on the most recent UN projections which revised previous projections upwards. The medium term of the UN population projections published in 2011 project that the world population will in fact reach 10.1 billion by the end of the century, rather than peaking at 9.5 billion by 2075 as assumed in the report.

The vast majority of world population growth over coming decades is projected to take place in developing countries, where food and water shortages are most prevalent. Yet an estimated 222 million women in developing countries want to avoid pregnancy but have an unmet need for modern contraception. Urgent investment in voluntary family planning services that respect and protect rights is required to address this vast unmet need, to ensure that women are able to makes choices about their own fertility. This strategy offers a proven and cost effective strategy for slowing population growth and helping achieve other development goals, and must be pursued alongside efforts to address unsustainable and inequitable patterns of production and consumption, including in the current food production and distribution systems.

The full report is available on the Institute of Mechanical Engineering’s website. 

This article by PSN summarises the Global Food: Waste Not, Want Not report, based drawing from the report’s executive summary and other materials by the Institute of Mechanical Engineer. The commentary about PSN’s response to the document has been added by PSN.