That is often just psychological so you have to resort to underhand tricks like drinking ice cold water, maybe fizzy water or even add a little lemon juice. Or eating cucumber, especially with the skin on.
Often though it can be boredom and doing something makes you forget about it.
Find a wedge of cheese works for me. Or homemade puddings, low carb variety, if that's what your missing. Love anything made with ground almonds, use tons of the stuff.