yudkin’s interest in sugar arose indirectly from his studies of the alarming increase in many countries during the first half of the twentieth century in the incidence of coronary thrombosis. this increase was of great concern to health professionals, and it was widely attributed to an increase in the amount of fat, or of a particular type of fat, in the diet. in a paper published in 1957 yudkin analysed diets and coronary mortality in different countries for the year 1952, and also analysed trends in diet, and trends in coronary mortality, in the uk between 1928 and 1954. the first of these analyses produced no evidence for the view that total fat, or animal fat, or hydrogenated fat, was the direct cause of coronary thrombosis; in fact the closest relationship between coronary deaths and any single dietary factor was with sugar. the second analysis, that of historical trends in the uk, found no good relationship with any single dietary factor. instead, it suggested that some change or changes in lifestyle during the past several decades was contributing to the increased incidence of coronary deaths. one obvious change was reduced exercise, and another was alterations in diet.