By combining the recognizable pumpkin spice flavor with sugar, you train your brain and body to remember how delicious the combination is -- and as soon as you smell or even imagine pumpkin spice, your body will have an anticipatory response and crave it, Franssen said.
For that reason, "the pumpkin spice latte is actually, scientifically, kind of addictive," she said. "Not quite the same neural mechanisms as drugs of abuse, but certainly the more you consume, the more you reinforce the behavior and want to consume more."
— NBC Montana talks to psychology professor Catherine Franssen about pumpkin spice. Read more at What is 'pumpkin spice' anyway? And why do we crave it?