an obstacle to the acceptance of these ideas was the belief at the time that sugar and starch were metabolised in the same way, so that one would expect no difference in their effects. yudkin and his associates, however, fed both experimental animals and human volunteers with differing quantities of sugar and starch, and found major differences between the two carbohydrates in their metabolic effects. unlike his colleague thomas l. cleave, yudkin believed sugar was more harmful than refined grains and refused to use the term "refined carbohydrates" because it gave "the impression that white flour has the same ill effects as sugar". as early as 1967 yudkin suggested that the excessive consumption of sugar might result in a disturbance in the secretion of insulin, and that this in turn might contribute to atherosclerosis and diabetes.