Whether you're grabbing a cup of coffee with friends, or downing an espresso before work, no one can deny that caffeine is a very important part of most American's days. This is exemplified in movies and television shows, like the 90s sitcom Friends, which portrayed six friends sitting around a coffee shop, enjoying each other's company as well as enormous mugs of coffee.

But was that portrayal of coffee consumption realistic? Scientific American estimates the number of caffeinated beverages consumed per friend over the show's ten year run ends up being about 3,100 gallons of coffee. Given the Starbucks standard of 410 milligrams caffeine in a 24 ounce brewed coffee, 3,100 gallons tops out at over six million milligrams of caffeine.

With few studies on caffeine dosage, it can be difficult for consumers to decide how much is too much. And with long work days and modern impediments to sleep, it can be tough to keep track of how much caffeine one has had.

There is no set overdose measurement for caffeine. However, based on some negative effects excess caffeine may cause, like restlessness, insomnia, and muscle tremors, caffeine intake ought to be monitored carefully.

Though Friends has portrayed coffee consumption without much negative effect, levels of caffeine consumption should not be taken lightly. Scientific American estimated that the amount drank on the show is enough to put 1,900 people in the hospital.