That's interesting! I looked up sugar addiction and found:
In 1998, Kathleen DesMaisons outlined the concept of sugar addiction as a measurable physiological state caused by activation of mu opioid receptors in the brain. Her work extracted data from studies done by Blass showing that sugar acted as an analgesic drug whose effects could be blocked by a morphine blocker. Acting on years of anecdotal evidence from her work in the field of addiction, DesMaisons noted that dependence on sugar followed the same track outlined in the DSM IV for other drugs of abuse.
Since that time, a growing body of laboratory evidence has corroborated DesMaisons' hypothesis. Bart Hoebel at Princeton began showing the neurochemical effects of sugar, noting that sugar might serve as a gate drug for other drugs.
In 2008, Nicole Avena published data stating that sugar affects opioids and dopamine in the brain, and thus might be expected to have addictive potential. She references "Bingeing," "withdrawal," "craving" and "cross-sensitization" are each given operational definitions and demonstrated behaviorally with sugar bingeing as the reinforcer.
Apparently sweet tastes (including sweeters) activate the opiate receptors. The same mechanism makes nicotine and heroin addictive ...