Boredom eater here, so I had to learn to keep my hands busy. Nowadays I don't really pay attention anymore, which is probably a very good thing.
Stuff that worked for me; maybe it'll work for you too?
- Reading while eating. I know, a lot of people, books and articles tell you that you shouldn't do anything else while eating, but the truth is, when you live alone and have no one to talk to, meals are frelling *boring* and you may very well end up shoveling down your food—usually too much of it. At least it was my case. When I've got something to do (reading, eating with other people...), I'm actually a slow eater, and by the time I'm done, I've reached the feeling of fullness without even realizing it.
On the other hand, watching TV (= hands not busy actually holding a book) has the same effect on me as eating alone without a book.
- It's a bit hardcore, and will depend on your personal taste: hot cocoa, the 100%, dark type, like Van Houten's. But not with milk: with hot water. You get the taste of chocolate, it feels quite filling, your mind's tricked into thinking "I got to have chocolate, yay!", yet the caloric intake is much lower. (Of course, it involves liking dark chocolate for starters. TBH, I started doing that out of a genuine mistake only, otherwise it'd have probably never occurred to me.)
My last tip involves having heavy teeth problems, so I won't recommend it.