New Evidence on the Effect of Medical Insurance on the Obesity Risk of Rural Residents: Findings from the China Health and Nutrition Survey (CHNS, 2004-2011).

The obesity rate in China has risen significantly in the past few decades. While a number of causes for the rise in obesity have been explored, little attention has been paid to the role of health insurance per se. This study aims to investigate the impact of health insurance on the risk of obesity in rural China using longitudinal data from the China Health and Nutrition Survey (CHNS). We employed pooled ordinary least squares (OLS), probit estimation, and pooled two-stage least squares (2SLS) for an instrumental variable (IV). The IV model revealed that New rural cooperative medical insurance (NRCMS) participation had a significant positive impact on people's tendency towards unhealthy lifestyles, for instances, high-fat food (8.01% for female and 7.35% for male), cigarette smoking (25% for male), heavy drinking (25% for female), sedentary activity (6.48 h/w for female and 6.48 h/w for male), waist circumference (1.97 cm for female and 1.80 cm for male), body mass index (0.58 kg/m² for female), which in turn leads to an elevated probability of general obesity (51% for female) and abdominal obesity (24% for female and 20% for male). An "ex ante moral hazard" is prevalent in rural China, which should not be ignored by policymakers so as to minimize the related low efficiency in the process of promoting the universal coverage of insurance.