The short answer is too much – about 1.6bn tonnes globally, or 3,000 tonnes every minute. If this wasted food was stacked in 20-cubic metre skips, it would fill 80m of them, enough to reach all the way to the moon, and encircle it once.
Much of this is lost from “farm to fork”, particularly in developing countries, where a large amount of edible food spoils before it can reach the end consumer, because of poor infrastructure.
In high-income countries, by contrast, food waste is most often caused by retailers and consumers over-purchasing and then throwing away edible food. In the UK, £20bn a year of edible food is wasted. Solving this will require widespread behavioural change in the rich world.