> noone is obese from eating too many potatoes

You get obese from eating too many calories, source is irrelevant. Sugars and refined foods are dangerous because they are particularly addictive. But if you crave carbs, and think potatoes are a "healthy" way to satisfy that craving, you're very wrong.

I mean, source kind of does matter, because potatoes are pretty filling. You would be hard pressed to eat enough potatoes to become obese at 110 calories a pop, unless you cover them in cheese and sour cream and meats, in which case it's not really the potatoes fault. I'm not saying they're a healthy diet option but you can't blame potatoes for someone being obese, which is what we're talking about.