With uncanny timing, the latest episode of South Park comes on the heels of a recently-published scientific report comparing the addictive quality of junk food to that of cocaine.
Published in Nature Neuroscience, the study, in which different groups of lab rats were tested for their responses to healthy and junk food diets, supports the idea that "compulsive-like eating behavior can emerge in extended-access rats in a manner analogous to the compulsive cocaine-taking seen in rats with a history of extended access to the drug." Seems the group of rats given only junk food became addicted enough that the rats would ignore deterrents like electric shocks in order to get their fix. The scientists build an analogy: today's junk food is to food a hundred years ago what cocaine is to the cacao leaf: processed, extracted, intensified to produce that mainline rush.
In the episode "Medicinal Fried Chicken," Cartman plays exactly this sort of rat. When he finds out that KFC has been made illegal in Colorado, he spirals into an abyssal panic and will stop at nothing to get his fix. In his autobiographical novel "Junky," William Burroughs says that "you don't know what junk is, until you've been junk sick." When Cartman descends into his own junk-food sickness, he winds up working for a Scarface-like underground KFC drug ring, hustling dealers, usurping his boss, and powwowing with a Pablo Escobar-tinged Colonel Sanders. Meanwhile Kyle's dad is possessed enough at the thought of legal weed that he gives himself ball cancer in order to procure a doctor's note. The doctor, perplexed by the subsequent rise in ball cancer among the father's friends, now thinks that, with junk food gone, he realizes what junk is: junk food was in fact keeping South Park ball cancer-free. In a characteristically dialectical twist, KFC is reinstated as MFC, medicinal fried chicken - the relation between food and substance undergoes a double inversion indexed by the very double-meaning of "junk." Food and drug are interrelated - no wonder we have a government entity called the Food and Drug Administration.