The sample consisted of 37 offenders with antisocial personalities and 31 with intermittent explosive disorders. No statistical differences existed in age, weight, or IQ, and both groups had committed their violent acts under the influence of alcohol, usually very impulsively. Subjects had been in prison and so without alcohol for over 5 months prior to the tests. Blood glucose levels fell below the basal level to a very low standard in both groups, but the return from reactive hypoglycemia to the original base values was very rapid for the intermittent explosive disorder group. It was also apparent that aspects considered to be typical of antisocial personalities were especially connected with their slow recovery from hypoglycemia. Marked insulin secretion can be an important factor among habitually violent offenders, and alcohol can increase more insulin secretion caused by the glucose level. Furthermore, habitual violent acts are usually committed under the influence of alcohol, especially by antisocial personalities. Differences in the groups can depend on the hormones released as a counterregulatory response in hypoglycemia. The results of this and previous studies suggest that the minority of hyperactive children who have poor outcomes may have a different etiology. Tables and 30 references are provided. (Author abstract modified)