An extensive analysis of the world's global food supply found we're losing more food to waste and overconsumption than previously believed. We eat 10 percent more food than we need -- obviously, some parts of the world consume far more than this average figure since 780 million are suffering from chronic undernourishment at the same time. Additionally, 9 percent of all the food we make goes to waste or spoils.
The study was conducted by Scottish researchers at the University of Edinburgh using data collected by UN's Food and Agriculture Organization. This kind of quantitative analysis at every stage of food production is extremely important if we're to meet the demands of a growing population sustainably.
The good news is we're making enough food for everyone. The bad news is we're quite terrible at distributing food and making it efficiently.
Food system losses were considered in six categories, as follows:
- Agricultural production: losses that occur in the production process. The losses include agricultural residues (e.g. roots and straw), unharvested crops and the losses during harvest.
- Livestock production: losses and inefficiencies in the conversion of feed and grass into animal products.
- Handling, storage, and transportation: losses due to spillage and degradation during storage and distribution. These losses occur for primary crops, processed commodities, and animal products.
- Processing: losses during the processing of commodities.
- Consumer waste: losses and waste between food reaching the consumer and being eaten.
- Over-consumption: the additional food intake over that required for human nutrition.
According to the Edinburgh researchers, half of the crops we grow -- that's 2.1 billion tonnes -- are lost to over-consumption, consumer waste, and inefficiencies in production. The results suggest that due to cumulative losses, the proportion of global agricultural dry biomass consumed as food is just 6% (9.0% for energy and 7.6% for protein), and 24.8% of harvest biomass (31.9% for energy and 27.8% for protein), the researchers wrote. But the most inefficient food production process is growing livestock, with losses of 78 percent or 840 million tonnes. About 40 percent of all losses of harvested crops can be attributed to livestock breeding which requires an immense amount of animal feed and water. Some 1.08 billion tonnes of harvested crops are used to produce 240 million tonnes of edible animal products including meat, milk and eggs.
"The results here suggest that system losses from over-consumption of food are at least as substantial as the losses from food discarded by consumers (Fig. 4), and therefore have comparable food security and sustainability implications. Consequently, greater research focus may be required to better understand causes, effects and solutions for over-consumption," the researchers said.
Globally, 14.5% of greenhouse gas emissions come from the rearing and butchering of cows, chickens, pigs and other animals – more than the emissions from the entire transport sector. That's because animals release methane, a highly potent greenhouse gas, while crops release carbon through land clearing and fertilizer use.
Bearing these stats in mind, an increase in consumption of meat and dairy products would disproportionately put more strain on the global food supply. This is a serious concern for the coming decades as more and more people in developing countries, from China to India, are improving their financial condition. In 1982, the average Chinese person ate just 13kg of meat a year. Beef used to be called the 'millionaire's meat'. Now, the average Chinese eats 63kg of meat a year and could consume 30kg more by 2030.
The researchers recommend in Agricultural Systems that people should eat fewer animal products. As we reported earlier, lower meat consumption would cut food-related emissions by 29%, vegetarian diets by 63%, and vegan diets by 70%. Reducing waste and being careful not to exceed your nutritional needs should also be a priority.
"Reducing losses from the global food system would improve food security and help prevent environmental harm. Until now, it was not known how over-eating impacts on the system. Not only is it harmful to health, we found that over-eating is bad for the environment and impairs food security," said Dr. Peter Alexander, of the University of Edinburgh's School of GeoSciences and Scotland's Rural College, who led the study.