Public health authorities have claimed that environment contributes to the obesity epidemic. For example, there are several studies (here and here) where researchers showed a high correlation between the number of fast-food restaurants and the obesity prevalence. Here is another not-so-surprising study from 2021 that concluded proximity (1-3 km) of fast-food restaurants to pre-school aged kids was also a factor. Indeed, the closer the kindergarten school was located to Western-type fast food restaurants, the higher was the obesity rate.
The researchers concluded that policymakers should consider regulating how fast-food restaurants are distributed near K-12 schools. You can even extend that suggestion to college campuses, where these restaurant are widely present, even in the student unions. From your experience, do you think this policy (restricting access) would be effective?