 Poppitt is originally from Cambridge, England.Her 1988 PhD thesis at Aberdeen University was titled " 'Energetics of reproduction and overwintering in some insectivorous mammals' ", supervised by Paul Racey and John Speakman FRS.. After graduation, she worked for Dunn Human Nutrition, both in Gambia and University of Cambridge and then moved to the University of Auckland, rising to full professor.She is the founding director of the University of Auckland’s Human Nutrition Unit.