View full lesson: ed.ted.com/lessons/how-sugar-affects-the-brain-nicole-avena When you eat something loaded with sugar, your taste buds, your gut and your brain all take notice. This activation of your reward system is not unlike how bodies process addictive substances such as alcohol or nicotine -- an overload of sugar spikes dopamine levels and leaves you craving more. Nicole Avena explains why sweets and treats should be enjoyed in moderation. Lesson by Nicole Avena, animation by STK Films.