Brain weights in alcoholics.

An analysis of the brain weights of 168 alcoholics showed that the mean brain weight of male alcoholics was less (p less than 0.001) than that of a normal population. Two subgroups of alcoholics were identified. Firstly, those with nutritional brain damage (Wernicke's encephalopathy, caused by vitamin B1 deficiency) and, secondly, those with brains which appeared "normal" macroscopically and microscopically. Any change in the brain weights of this second group was unlikely to be caused by nutritional damage. Both groups had abnormally low brain weights which suggests that alcohol, the factor common to both groups, is more important than nutritional deficiencies in causing brain damage and a reduction in brain weight.