I have found this article: https://www.bmj.com/rapid-response/2011/10/29/myopia-possible-link-increased-refined-carbohydrate-intake-and-hyperinsuli
which by no means is a hard evidence by itself but it suggests that western diet that is high in refined carbs and sugars may be the one to blame for the rapidly increasing prevalence of myopia.
Those statements are based on the fact that some formerly hunter-gatherer communities who adopted the western way of living (schooling and foods) went from 1-2% to 50% in myopia prevalence in under a generation.
Communities that adopted schooling but not diet (mostly on rural areas) are not nearly that much affected.
Do you think high sugar / high carb diet could contribute to myopia progression? Do you think their explanation with IGF-1 makes sense in this case?