Dieting is as much an American pastime as baseball or the 4th of July. We've adopted weight-loss trends from countries near and far, and we've eaten (and not eaten) foods that promise to help shed pounds faster than ever before. You may think you've heard it all, but there's a whole century of forgotten American diet trends to look back at, and (if you're brave enough) try out! Move over Ducan and Dr. Atkins, because we're bringing back these retro-diets.

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