- Eating a varied healthy diet is a lot more expensive than eating a varied unhealthy diet (if you can eat kale, rice, and beans all day then good for you but most can't)
- We're creatures of habit, if we grow up eating unhealthy we are more likely to continue to as adults. Eating healthy for most people requires cooking for yourself, many never learn this skill or see their parents putting daily effort into meals when they are children.
- Lack of public education around the topic, lack funding for free healthy lunches for school children
I had a friend when I was in school who had the most messed up disgusting teeth I'd ever seen. He had dental insurance, a decent job, decent pay. Turns out he never grew up learning that you're supposed to brush your teeth regularly so he just never made a habit out of it.