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Ensuring adequate supply of food is the most important challenge facing China. With the dramatic change in food habits over the past few decades, the demand for arable land and irrigation water has also changed, undoubtedly increasing the uncertainty of ensuring China's food security. This study quantifies how China's food habits have influenced the requirements for arable land and water between 1981 and 2016 using data collected from multiple sources and projects the amount of arable land and irrigation water needed to ensure national food security. The results show that changes in food habit have led to increased demand for arable land and irrigation water during the past 30 years. In 1981, 124 million ha of arable land and 159 billion m(3)of irrigation water were needed for food consumption; however, these values increased to 137 million ha and 184 billion m(3), respectively in 2016. Moreover, changes in food habit have exceeded the level of agricultural technology, becoming the main reason for increase in per capita demand of arable land and water after 1996. Under the current food habits, the demand for arable land and irrigation water will increase by 14% and 13%, respectively when the expected population peak occurs (in 2032), compared to those of 2016. However, if the food habits recommended by China's nutritionists are followed in the future, more arable land and irrigation water will be needed to meet China's demand compared to the current diet patterns. This study also proposes some measures to ensure China's food security based on the presented findings. (C) 2019 Elsevier Ltd. All rights reserved.