Soybean overweight shock (SOS): The impact of trade liberalization in China on overweight prevalence

This study investigates the overweight effect of the soybean import shock (referred to as the soybean overweight shock or "SOS") on China, the largest importer of soybeans worldwide. By using China's soybean import liberalization in 1996 as a natural experiment, which involved the removal of soybean tariff rate quota (TRQ) policy and a reduction in soybean import tariffs from 114% to 3%, we found significant SOS effects. The soybean import shock can account for 10.76% of the observed increase in overweight probability between 1989 and 2006. Mechanism analysis finds that the exposure to the soybean import shock leads to a significant decrease in the market price of soybean oil and an increase in soybean oil consumption, it also increases the likelihood of being overweight through dining out, eating food prepared outside, and eating fried foods. Additionally, we discovered stronger SOS effects in urban residents, females and individuals with relatively lower family income.