I'm going to encourage my boyfriend to have unhealthy behaviors
What makes you want to encourage unhealthy habits for your boyfriend?
I want make him to feel bad about himself physically
You shouldn't want your boyfriend to engage in unhealthy behaviors. If you can't support your partner, and want them to feel bad about themselves you shouldn't be together.
I think it's fine, it's for his own good.
Him developing bad behaviors is not for his own good. I hope you think more about this and try and help him instead of hurt him.