Step 1 : Introduction to the question "Drinking how many grams of caffeine results in an overdose?"
...Determining exactly how many grams of caffeine consumed constitutes an overdose is not settled science. According to the "Journal of Caffeine Research," overdose range for adults is approximately 10 grams. An article by Forensic Science International in 2005 listed the figure closer to 5 grams. Consuming a normal cup of coffee brings the caffeine level in the blood to between 2.5 mg and 7 mg/L, on average. To get to an overdose level above 5 - 10 grams, you'd have to drink over six gallons of coffee. Source: PopSci.com
