This question doesn't have a set answer I dont believe. How often should you be hungry? It varies from person to person and metabolism and other factors. I'm a skinny girl and I'm deffo hungry after 3-4 hours and can eat anytime really lol. Except if I have a monster dinner with an app, soup, and dinner. Even an hour after that I would take a Starbucks drink; just using that as example since that's what we did on date night on Friday night.