Effects of diet on the cellular insulin binding and the insulin sensitivity in young healthy subjects

Abstract

To ascertain whether the effects of diet on glucose tolerance and insulin sensitivity are mediated through changes of insulin receptors we have studied insulin binding to monocytes in 24 young volunteers (4 groups of 6) during 2 week periods of different dietary regimens. In group 1 and 2 the subjects had their usual diet plus 1000 kcal per day from sucrose or fat, respectively. Group 3 had an isocaloric diet with a low-sucrose content, while group 4 ate low-fat high carbohydrate diets. Before change of diet the total group of volunteers showed an inverse correlation between insulin binding and average daily sucrose intake (R = - 0.52, p<0.01). An excessive sucrose consumption (group 1) was associated with a reduction both of insulin binding (p<0.05) and insulin sensitivity (p<0.05). The changes of the two variables were parallel (R = 0.95, p<0.05). An abundant fat intake (group 2) was also accompanied by a decrease of insulin binding (p<0.05). However, insulin sensitivity was unaltered (p>0.1). A rise of insulin binding (p<0.05) followed the isocaloric, low-sucrose diet (group 3) whereas the insulin sensitivity was unchanged (p>0.1). After the isocaloric, low-fat diet (group 4) no significant change of insulin binding occurred (p>0.1) whereas the insulin sensitivity increased (p<0.05). We conclude that diet and especially the dietary sucrose content affect insulin binding to human monocytes. Evidence is presented that changes of insulin sensitivity following hyperalimentation of sucrose may be induced through alterations of insulin receptors. © 1978 Springer-Verlag.