Caffeine addiction/consumption

Hughes, G. V., and Boland, F. J., The effects of caffeine and nicotine consumption on mood and somatic variables in a penitentiary inmate population. Addictive Behaviors 17(5), 447-457, 1992. 

Graham, K., Reasons for consumption and heavy caffeine use Generalization of a model based on alcohol research. Addictive Behaviors 13(2), 209-214, 1988. 

So what is the big deal Although there is still plenty of debate about caffeine and its effects on the body, empirical evidence has shown that large quantities can cause significant health and behavioral problems. For instance, too much caffeine can result in nervousness and insomnia. The insomnia causes fatigue, leading to more caffeine consumption, more insomnia, more lack of sleep, irritability, and so on. Additionally, increased caffeine consumption appears to correlate with an inaease in bone loss and occasionally, abnormal heart rhythms. Addiction to caffeine is possible, with unpleasant symptoms resulting upon cessation of use. 

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