New research explains why food waste is low in the Philippines but high in Belgium.

The world wastes twice as much food as previously estimated — and rich countries are disproportionately responsible

Markets allow harvested vegetables to rot; families throw out leftovers. These and other forms of loss and waste claim one-third of the world’s food supply, according to an estimate by the United Nations Food and Agricultural Organization (FAO).

Monika van den Bos Verma of Wageningen University and Research in The Hague, the Netherlands, and her colleagues wanted to explore how consumer affluence affects food waste. The researchers drew on 2003 data collected by the World Health Organization, the FAO and others to estimate calories purchased, calories consumed and calories wasted by people around the globe.

Belgium had the most food waste, and the Philippines had the least. (The study covered two-thirds of the world’s population, and did not include large food-wasting countries such as the United States.) As household spending rose above roughly US$6.70 per day per person, the amount of food waste also rose quickly, but then slowed.

Globally, people waste 527 calories per person per day — more than twice as much food as scientists had thought.