That's correct.
There are a number of jurisdictions that looked at improving food literacy and the impact of those didactic sessions on behaviour. I would say that they're not non-existent, but they're dwarfed by the power of marketing that kids are subjected to.
The budget for marketing unhealthy foods and beverages to kids is over $1 billion per year. It uses sophisticated marketing spokespersons, sportspeople, cartoon characters. It's pervasive. It's all the way through the Internet and social media. There are billions of views per year in social media. It's a cannon compared to the popgun of media literacy.