Some practical things which have worked for me, though:
Distraction, distraction, distraction - just white-knuckle it for a while as you get into watching or reading something really interesting (your favourite TV show, a much-anticipated book) and you may be able to ride it out to the point that you kind of forget the urge and it lessens.
Drinks - I agree with Paula that filling up on hot drinks helps. Love bone broth or bouillon, and a frothy and delicious smoothie can fill you up something wicked.
Exercise – a few minutes sweating it out on a bike tends to get the endorphins going for me. Dancing would be good too. Sometimes it's just the act of *starting* to do something positive for myself which swings my brain into the mode of wanting to continue to do something positive for myself. This is why I try to drag my lazy backside onto the bike as soon as I get out of bed in the mornings – I'm not keen to start with, but I do feel so much better afterwards and it kick-starts my day going in the right direction, and for some reason immediately makes me want to eat better too. I'm thinking of trying a pre-dinner exercise burst too, to see if it influences me into making better choices.
Paula – can you share some more about your knowledge of and experiences with L-glutamine?