Do you mean general you or specific you? If the former, then there are definitely calorie/fat dense foods that aren't considered junk food that could get one there, as others have mentioned, although you might have to actually be trying in order to go from average or low weight to being morbidly obese from eating them. For me personally, I couldn't do it because I can't eat a whole lot in one sitting before my body refuses to swallow any more. In fact, I do eat a significant amount of junk food and, at 5'5.5" in height, have never weighed more that 115 pounds, probably because of high metabolism and a small appetite. I'm usually around 100-105 pounds.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"