 Gary TaubesSelf - Author | Self - Author |
 Robert LustigSelf - Doctor of Pediatric Endocrinology | Self - Doctor of Pediatric Endocrinology |
| CCraig WilcoxSelf - Researcher, Okinawa Centenarian Study | Self - Researcher, Okinawa Centenarian Study |
| AAlexis GomezSelf - Former Patient of Dr. Lustig | Self - Former Patient of Dr. Lustig |
| CCristin KearnsSelf - Dentist, Denver, Colorado | Self - Dentist, Denver, Colorado |
| YYoni Freedhoff M.D.Self - University of Ottawa | Self - University of Ottawa |
| JJean-Marc SchwartzSelf - Biochemist | Self - Biochemist |
 John YudkinSelf (archive footage) | Self (archive footage) |
| AAncel KeysSelf (archive footage) | Self (archive footage) |
| SSami InkinenSelf - Endurance Athlete | Self - Endurance Athlete |
| DDr. John L. SievenpiperSelf - Researcher, St. Michael's Hospital, Toronto | Self - Researcher, St. Michael's Hospital, Toronto |
| TTerry DeanSelf - Heart and Stroke Foundation | Self - Heart and Stroke Foundation |
| FFrank LisciandroSelf - Filmmaker | Self - Filmmaker |
| SSheldon ReiserSelf - Researcher at the U.S. Department of Agriculture | Self - Researcher at the U.S. Department of Agriculture |
| JJudith HallfrischSelf - Nutritionist | Self - Nutritionist |
| SStan GlantzSelf - Head of the Tobacco Research Unit, University of CA | Self - Head of the Tobacco Research Unit, University of CA |
| AArya SharmaSelf - Medical Director, Canadian Obesity Network | Self - Medical Director, Canadian Obesity Network |
| KKim RaineSelf - Alberta University | Self - Alberta University |
| RRichard EllisSelf - McDonald's Canada | Self - McDonald's Canada |
| LLaura SchmidtSelf - Faculty of Medicine, University of California | Self - Faculty of Medicine, University of California |
| MMeredith InkinenSelf - Endurance Athlete | Self - Endurance Athlete |
