The increasing concern of the policy maker about eating behavior has focused on the spread of obesity and on the evidence of a consistent number of individuals dieting despite being underweight. As the latter behavior is often attributed to the social pressure to be thin, some governments have already taken actions to ban ultra-thin ideals and testimonials. Assuming that people are heterogeneous in their healthy weights, but are exposed to the same ideal body weight, this paper proposes a theoretical framework to assess whether increasing the ideal body weight is socially desirable, both from a welfare and from a health point of view. If being overweight is the average condition and the ideal body weight is thin, increasing the ideal body weight may increase welfare by reducing social pressure. By contrast, health is on average reduced, since people depart even further from their healthy weight. Given that in the US and in Europe people are on average overweight, we conclude that these policies, even when are welfare improving, may foster the obesity epidemic.JEL classification: D91, I18.

The increasing concern of the policy maker about eating behavior has focused on the spread of obesity and on the evidence of a consistent number of individuals dieting despite being underweight. As the latter behavior is often attributed to the social pressure to be thin, some governments have already taken actions to ban ultra-thin ideals and testimonials. Assuming that people are heterogeneous in their healthy weights, but are exposed to the same ideal body weight, this paper proposes a theoretical framework to assess whether increasing the ideal body weight is socially desirable, both from a welfare and from a health point of view. If being overweight is the average condition and the ideal body weight is thin, increasing the ideal body weight may increase welfare by reducing social pressure. By contrast, health is on average reduced, since people depart even further from their healthy weight. Given that in the US and in Europe people are on average overweight, we conclude that these policies, even when are welfare improving, may foster the obesity epidemic.JEL classification: D91, I18.

Policy interventions aimed at affecting a specific behavior may also indirectly affect individual choices in other domains. In this paper we study the direct effect of tobacco excise taxes and smoking bans on smoking behavior, and the indirect effect on eating behavior and body weight. Using very detailed clinical data on individual health, smoking, and dietary habits, we show that antismoking policies are effective in reducing smoking, but their consequences on eating behavior dramatically depend on the specific implemented policy. Increasing excise taxes on tobacco decreases body weight and caloric intake, and it improves the quality of eaten food. Smoking bans, instead, do not significantly affect body weight, although they impact on the diet composition. Smoking bans in restaurants induce a significant rise in the quality of food and in daily caloric intake. Conversely, smoking bans in bars negatively affect the quality of the daily diet, as individuals eat more fats and less fibers, and drink more alcohol and caffeine.

The debate on tobacco taxes and fat taxes often treats smoking and eating as independent behaviors. However, since there exists medical and sociological evidence about the interdependence between eating and smoking choices, antismoking policies may also affect the obesity prevalence and fat taxes could influence smoking behavior. We address this issue from a theoretical standpoint and propose a dynamic rational model where eating and smoking are simultaneous choices that jointly affect body weight and addiction to smoking. Focusing on direct and cross price effects, we compare tobacco taxes and fat taxes and we show that a single policy tool can reduce both smoking and body weight. In particular, fat taxes can be more effective than tobacco taxes at simultaneously fighting obesity and smoking.

The debate on tobacco and fat taxes often treats smoking and eating as independent behaviors. However, the available evidence shows that they are interdependent, which implies that policies against smoking or obesity may have larger scope than expected. To address this issue, we propose a dynamic rational model where eating, smoking, and physical exercise are simultaneous choices that jointly affect body weight and addiction to smoking. Focusing on direct and cross-price effects, we study the impact of tobacco and food taxes, and we show that in both cases a single policy tool can reduce both smoking and body weight. Copyright © 2015 John Wiley & Sons, Ltd.