What problems does my everyday monster cause, who does it affect, and how can it be solved?

It can give you cancer and you could die if you drink more then 3 of them ... caffeine overdose (which can lead to a number of symptoms, including palpitations, high blood pressure, nausea and vomiting, convulsions and, in some cases, even death) type 2 diabetes - as high consumption of caffeine reduces insulin sensitivity. It can be solved if you don't drink the damn thing!