Many later editions changed nothing from the original 1975 text except to hide the author's promotion of Eugenics and open racism. However, other editions have left this in. The diet was designed, not on any in-depth studies or science, but to create a 'superior race'. The author is explicit and repetitive on this point. From the book, “Geneticists have for decades deplored the unfortunate restrictions of civilization that allow the human race to breed with much less intelligence than is applied in breeding our cattle. Effective eugenics, if such were possible could quite rapidly eradicate hereditary disease and undesirable mental and physical traits while enhancing desirable mental and somatic attributes. ” This book belongs in the trash.