I know this question is a little old but I hope someone finds this post useful.
I find having very consistent eating times makes my cravings go away. When I eat my breakfast at 7:30, my lunch at 12, and my dinner at 6 I never have any trouble with regards to cravings. My body knows what's coming and it does need anything else!
Also if you find you can't stop cravings, buy some healthy snack alternatives. Instead of trying to resist them completely replace the unhealthy foods with some carrots. I find carrots a great snack for getting through a craving or just a hungry point in the day.
I envy people who can do this - replace unhealthy foods with a carrot.
Uhm...yeah. Great idea. But I don't want a carrot. I want chocolate. A carrot is not going to do anything about the chocolate craving, because it is not about eating 'something'...it's about chocolate (or any other 'crave-food' of choice). So that never works for me.
For me, the way to get a grip on cravings is not to have the stuff in the house that I crave. If what I want is not there, I won't eat anything.
As for eating at certain times - I wish I could, but my life doesn't even allow me to sit down for meals - I eat whenever I get a moment's peace (usually when I am at the computer), because I don't know when I'll get the next chance.
It's about planning. If you put yourself in a position where a healthy snack is readily available to you, it's a lot easier to choose it. Choosing a healthy snack when you're hungry/craving is going to be very difficult for anyone, including myself. Having the snack prepared in advance to you getting hungry/craving helps a lot.
Why not have healthy snacks that you do like then?
I like carrots as a snack, not as much as chips of course, but they'll do most days.