This can be a response to a blood sugar spike and crash. Your body will send you screaming for sweets if it thinks it's dying, and rightly so. Your job is to prevent it from thinking that way.
Sugar starts digesting in your mouth with enzymes to break it down. The mere thought of something sweet gets your mouth watering with them.
This is pure trigger and response. There is no need for snacking in front of the tube. Just turning on the TV is enough to set you up for stimulus and input.
Time of day trigger! Identify what you need from this habit -- is it the caffeine, the sugar or the break?
The less your drink the better. The Canadian Liver Foundation says even a small amount can be damaging. The trick is to be honest with yourself about how much you drink.
How many times have you kept eating when you knew you were already full? Ask a North American when they know they are finished a meal and they will say "when the plate is empty" but a European will say "when I can no longer taste it, or am not aware I am eating"