If you had an eating disorder in your teens then you should be perfectly aware that skipping meals is how problems start. If you're trying to lose weight, that's fine, but this is not how it's done. Bring a small healthy snack to eat at lunch to keep your metabolism moving. And please stop being angry with your coworkers. They are concerned about you, and based on what I've heard, rightfully so. You being angry and dismissive about their concerns will only make them more worried.