If you've already covered food addiction in this conversation, please ignore this post. But I'm going to toss in my 'terminology rant' just in case no one else has mentioned it yet...
I really abhor the term 'carbohydrates'. It's FAR too general.
It's not the fault of the general public but this is what all the advertising and diet hype promotes. People who write diet/cook books should know better than to lump grain in with vegetables. They are NOT the same but they ARE valid carb suppliers.
When people talk about carb cravings - really they're only talking about grain. You never hear them talk about carrots or squash.
"Oh I just had to eat that huge plate of squash today!"
The difference between a carb from a fruit/vegetable and from a grain are worlds apart.
Gluten (wheat, rye, barley, oats) has been noted to have a systemic response in the brain that is very close to opium. (check out pubmed)
Yes, foods can be addictive. We don't really need science to tell us this though. Look at what manufacturers are putting in their 'recipes'. They test and retest to see what will make us want to eat more of their product.
Any addiction has a 'got to have it' and a depression that follows when the brain synapses empty out.
We recognize this cerebral response in smoking, drinking, drug use but we currently do not give much validity to the same response with food. Some people claim it is the power of the food boards (wheat board, etc.). That may or may not be. I think that it's just so widespread that people accept it as a 'normal' part of life and are taught not to question it.
Okay... I'm done now.