The Mystery of Who Came Up with the Grapefruit Diet
                                
                                
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                                    4 min read                                
                            
                                The originator of the highly restrictive grapefruit diet, a fad that first appeared in the 1920s and 1930s, is completely unknown. This eating plan gained notoriety for its promise of rapid weight loss through a so-called "fat-burning enzyme," though this claim was never supported by science.