In a "mentally healthy" human, the desire to eat goes away almost immediately after you start eating, and it doesn't come back for another 4-8 hours, so it's really difficult to consume more than you'd need without purposefully choosing to eat more. This is why I list it as a "mental health concern", specifically avoiding the word "issue".

I'm trying to distance the thought train away from the "practicality of just eating less", because it doesn't work that way anyway.

Poor food literacy and understanding of health usually relates to an unstructured upbringing or trouble at home, also raising a mental health concern.

There are also significant cultural considerations. In my country, for example, male obesity is highly regarded as a sign of success and abundance, and these men prefer "curvy" women - our per capita obesity is worse than USA, even though we don't have access to high fructose corn syrup at all, and we have a massive government imposed sugar tax, so almost nothing has sugar in it anymore!