Unpacking the decline in food waste measured in Chinese households from 1991 to 2009

Food waste reduction is an explicit goal for many countries, yet a paucity of high-quality primary measurements of food waste are available to inform policy. We analyze repeated physical measurements of discarded food from more than 37,000 households enrolled in the China Health and Nutrition Survey (CHNS) from 1991 to 2009 and describe relevant food waste patterns and trends within households over a period of dramatic change. Over a period in which average real household incomes tripled, food discarded per person declined by about 20% on a quantity basis and by about 40% on a Calorie basis during the study, with an estimated annual per capita household waste of 14.9 kg in 2009. Comparing across households within narrower periods of the data, we find changing associations between income and food waste, with a weakly negative association during the 1990s and a significant positive association during the 2000s. Carbohydrates, particularly grains and vegetables and fruits, experienced the greatest reduction in waste. Food waste reduction rates over the study period were greatest among small households and rural households. Certain characteristics were associated with higher per person waste levels throughout the study period, including rural residence, intense physical activity levels, and a lack of home refrigeration.