Terry D. Etherton
Much has been written by others and myself about the need to feed a growing World population that will increase to between 9 and 10 billion individuals by 2050 (based on estimates from the Population Estimates and Projections Section of the UN). Making projections about the impact of population growth on food production raises the question of just how much food will be required to feed 10 billion people? While the question is straightforward, developing these estimates is remarkably challenging. The vast majority of numbers are derived from food disappearance data, that is food for human consumption that is produced is assumed to “disappear” via consumption. This is problematic, in part, because it has been estimated that 30 to 40% of food in developed and developing countries is wasted (Godfray et al., 2010). This wastage spans the spectrum of the food system from production to plate waste.
The question emerges, then, of whether there is more accurate approach for estimating projected food needs in 2050?
Inherent to any approach that is developed to estimate food production needs in 2050 is the reality that this must be considered in the context of the numerous events that could affect food needs and production capacity. These include aligning food production needs to the rapidly changing demand from a larger and more affluent population; doing this in environmental and socially acceptable ways; and ensuring that the world’s hungry are no longer hungry! Moreover, achieving this goal of adequate food production in 2050 also presumes that future climate change will not hinder food production, and that geopolitical strife will not disrupt food production (and distribution).
As I have written in Terry Etherton Blog on Biotechnology, growing food production by 2050 to meet population needs will require an increase in funding for science and technology. This raises the question of “who pays for this”? Related to this question is another daunting question: how will private sector companies that develop these new biotechnologies distribute them to developing countries, and at what price? Another pressure point on feeding the world in the future is the development of biofuels. The current business model of diverting feed grains, such as corn, to ethanol production is folly.
There have been numerous estimates of future food needs. In a report published by the World Bank, World Development Report 2008: Agriculture for Development, it was estimated that cereal production would have to increase by 50 percent and meat production by 85 percent from 2000 to 2030. This is similar to a report (Reaping the Benefits: Science and the Sustainable Intensification of Global Agriculture) published in 2009 by the Royal Society. Other estimates are that we will need 70 to 100% more food by 2050 (Godfray et al., 2010). In none of these estimates is the percentage increase translated to quantity of food actually needed.
To estimate future food needs, I used information about energy and nutrient requirements for men and women that were published in the Dietary Guidelines for Americans 2010, specifically the USDA Food Patterns (Appendix 7). I used two levels of dietary energy intake for women and men that are commonly used “benchmarks” for individuals at a healthy body weight. For women, this is 2000 calories per day and for men it is 2800 calorie per day. The USDA Food Patterns information translates recommended nutrient requirements to recommended daily intake for each food group (i.e., fruits, vegetables, grains, protein foods, dairy and oils) to a mass basis (i.e., cups or oz).. This approach permits the calculation of the quantity of food needed to meet daily nutrient needs for an individual.
Based on the above, the quantity of food needed daily for a healthy diet can be determined (1.93 kg/day for men and 1.6 kg/day for women) . This information can be used to calculate current and projected consumption (on an annual basis). Based on the current population of 6.8 billion people in the World, the estimated food production need is about 9.9 trillion pounds per year. In 2050, it is about 14.3 trillion pounds per year or an approximate 44% increase, which aligns with other estimates. If you are “wrestling”, as I am, with how to scale a “trillion”, consider that 1 trillion seconds is equal to 32,000 years!
There are several obvious constraints to these estimates. First, there are over a billion individuals in the World who are malnourished and are eating a diet that meets neither nutrient nor energy requirements. Conversely, there is a large and growing cohort of overweight and obese individuals that dramatically over-consume both nutrients and calories. Nonetheless, the evidence presented herein is based on an approach that accurately quantifies the amount of food we need to produce based on meeting nutrient and energy needs of normal weight individuals.
The results are telling in that considerable progress could be made to meet future food needs by reducing food wastage over the spectrum of the food system. This, of course, will be enormously difficult to do. As one example, can you envision a strategy that would effectively “redirect” food from individuals/countries that over-consume food to those who are in an energy and nutrient deficit? I can’t and this reinforces the reality that meeting future food production needs will be incredibly challenging and, most likely, costly. This does not bode well for having enough food in the World by 2050.