The two scientists effectively piggybacked on one another. In the post–World War II editions of Joslin’s textbook, he cited a 1935 article by Himsworth as the support for the statement that increased fat consumption explained the rising incidence of diabetes.*31 Himsworth’s article, in turn, rejected the hypothesis that sugar caused diabetes by citing a 1934 article by Joslin and a 1930 article by C. A. Mills of the University of Cincinnati. Joslin’s 1934 article also depended almost entirely on Mills’s article. Mills’s article had stated “that there is no evidence in support” of the sugar-diabetes hypothesis; he had based this statement almost entirely on the observation that in Norway, Australia, and elsewhere sugar consumption rose from 1922 through the end of that decade but diabetes mortality did not. Other investigators, however, Joslin included, noted that the discovery of insulin in 1921 naturally led to a temporary leveling off of the otherwise rising tide of diabetes mortality. (On the other hand, as Mills noted, “of the thirteen countries highest in consumption of sugar, eleven are found among the thirteen highest in death rate from diabetes.”)

Himsworth’s achievements in clinical research were notable. He may have been the first researcher to differentiate between juvenile diabetes, caused by the inability of the pancreas to produce sufficient insulin and now known as insulin-dependent or Type 1 diabetes, and non-insulin-dependent diabetes, or Type 2, primarily a disease of adults, linked to excess weight and characterized by an insensitivity to insulin. Himsworth would later be knighted for his research contributions. Regrettably, his epidemiology was not as good as his clinical research.

Himsworth had first become convinced that diabetes was caused by fatty diets after asking his patients about their eating habits prior to their diabetes diagnosis and being told they had consumed “a smaller proportion of carbohydrate and a greater proportion of fat” than did healthy individuals.