The feeling is usually brief. By the time you’re licking the chocolate off your fingertips or picking the last crumbs of biscuit from the plate, your dopamine levels will probably have fallen, taking you into a mini-withdrawal.
This can prompt desires for more cubes of sugar, urging you, against your better decision, to pick up another biscuit or break off another square of chocolate so your brain can have another hit of dopamine. Before long, the biological signals that would normally control hunger and satiety (fullness) are swiftly being overwhelmed by this dopamine stimulation, to the point where your body (and brain) starts listening only to sugar’s cues and ignores the fact that you have already eaten far more than you need. If you have even the mildest addiction to sugar, there is every chance that your ‘off’ switch no longer works properly in response to eating, either. That’s why one biscuit or scoop of ice-cream never seems like enough, even after a huge meal.
Study as it that the more sugar you consume, the more your tolerance adapts, hence you end up demanding for more and more sugar to get the same boost – drug addicts and alcoholics experience the same cycle.