A wasted orange.Waste not, want not: In order to meet global food demand, we should decrease food waste instead of expanding agriculture.Photo: Christoph LupprichCross-posted from Cool Green Science.

A new report by the Food and Agriculture Organization (FAO) of the United Nations finds that globally, roughly one-third of all food produced for human consumption is wasted.

But why is that bad news — and potentially good news — for nature?

First, the bad news: Agriculture is the dominant way people use land, covering about 12 billion acres, roughly 36 percent, of the Earth’s land surface — and conversion of land to agricultural purposes is one of the primary threats to critical habitats like grasslands, forests, and even deserts. When you waste one-third of the food that agriculture produces, it’s adding insult to injury for nature.

The picture might look even bleaker when you consider that global food demand is expected to double between the years 2000 and 2050 — as the planet’s population increases, gets wealthier, and eats more meat (the production of which often consumes tremendous amounts of land and resources). Even with projected increases in global crop yields, the area planted to cropland by 2050 is expected to increase by 170 million acres, an area larger than France or Afghanistan.

But here’s the potential good news: What if much of this increased demand for food could instead be met simply by decreasing food waste instead of by expanding agriculture? That would mean more land left over for nature and other human needs.

To answer this question, we need to know not just how much food is wasted, but whether it is possible to reduce this waste. Although the report makes a strong case that waste reduction is possible, unfortunately it did not estimate how much waste reduction is possible (since zero waste is not a practical goal).

Waste reduction can occur either before or after it is purchased by the consumer, and separate strategies for food waste reduction are needed in each case. Consumer food waste is largely restricted to rich countries, because poor people can’t afford to let food go to waste. In contrast, “pre-consumer” losses during processing, storage, and transport are most acute in poor countries, which lack infrastructure to effectively store, transport, and process food.

This suggests two separate strategies, one for rich countries and one for poor countries. In rich countries, consumer education about food waste could potentially help improve consumer habits related to food waste (although the amount of benefit that can be achieved with consumer education is unclear). In poor countries, improving infrastructure could reduce pre-consumer food waste.

Another piece of good news: Conserving nature can begin at home for Americans, by reducing all kinds of waste — including food. The average American wastes over 200 pounds of food each year. That means that a household that eliminated its food waste could save over an acre of habitat from being converted to farmland. There are a lot of ways that consumers can reduce food waste — just buying what you need, for example — that also save money.

In poor countries, there is a need for increased investment in all aspects of agriculture, and this is especially true in Africa. Improved infrastructure that reduced the level of pre-consumer waste in sub-Saharan Africa to the same proportions seen in the most efficient industrialized parts of the world would lead to tens of millions of tons of avoided food waste every year.

Using data from the FAO’s report, I estimate that simply bringing levels of waste in sub-Saharan Africa down to those achieved elsewhere in the world would save an amount of food equivalent to adding 53 million acres of cropland — but without actually converting a single additional acre of natural habitat to that cropland. Just another example of conservation that is good for both people and nature.