persons with schizophrenia not only smoke, but they intake caffene, alcohol and illigal drugs in much higher quantitie than the average person.. It's all about self-medication, whether they are aware of that or not. Various drugs can moderate, not only the symptoms of the disease, but the side affects of their perscription drugs.

With a disease that literally hijacks a person's mind, ANY control, no mater how minor, and no matter how it's accomplished, is a good thing.