Obesity may not only be linked to undesirable health outcomes but also to
limitations in sexual life. The present paper aims to assess whether there is a causal relationship between weight loss and sexual activity in adult obese individuals. To address the endogeneity of weight loss that is likely to result in biased estimation results, the analysis is based on data from a randomized field experiment. In this experiment, financial weight-loss rewards were offered to a random subgroup of participants and can be used as an exogenous source of weight variation in an instrumental variables approach. Estimation results indicate that for obese males losing weight, both the probability of being involved in a sexual relationship and the frequency of sexual intercourse increases. The same pattern of results is found when pooling both sexes in the sample. Due to the small share of women in the sample, the analysis yields no reliable results specifically for females.
