The definition of addiction has been expanding all over the place, with rehab programs springing up for Internet addicts and class action lawsuits hinging on whether gambling falls under the addiction umbrella. Given the latest obesity studies proclaiming the eventual corpulence of everyone in America, it's worth asking: Is overeating an addiction, and should it be treated like one? So far, research on obesity has followed pretty much the same line as research on gambling, Web surfing, and other compulsive behaviors: When the brains of an overeater, compulsive gambler, etc. are examined, their increases and reductions in dopamine receptors follow similar patterns to those in drug addicts. Now, a new drug developed to treat drug addition has also been shown to cause rapid weight loss. Called vigabatrin, the drug is currently in the clinical test phase for cocaine and methamphetamine dependence. After examining earlier evidence of a strong connection between obesity and cocaine addiction, researchers at Brookhaven Lab decided to test the drug's effect on weight loss. Sure enough, when they administered it short-term to obese and regular-weight animals, the former lost up to 19 percent of their total weight, while the latter lost between 12 and 20 percent. Certainly all these drug addiction/obesity links bolster the findings that obesity is tied to genetics. Still, classifying obesity as a form of addiction runs the risk of minimizing the cadre of other factors, from modern technology to socioeconomics, that have been shown to contribute to the current epidemic. Or maybe they've all joined together to form a perfect obesity storm. Either way, unless we take quick action, predictions that once sounded ridiculous may start to come true.