How many cups of coffee would it take to kill you?

I'm not sure that our society would be able to survive without caffeine. How many of us need at least one cup of coffee in the morning before we can function at a level even approaching 'human'? However, is the drug a hidden killer, just waiting for us to down that next latte or energy drink to pounce?

Just last week, a lawsuit was filed against Monster Beverage Corp that claims their energy drink caused the death of a 14-year old Maryland girl. It seems that she had a preexisting medical condition known as Ehlers-Danlos syndrome, which is a group of genetic disorders related to problems with collagen, that cause loose joints, hyper-elastic skin, and — likely the most important factor in this girl's case — easily damaged blood vessels. However, according to the autopsy report, it was apparently the cardiac arrhythmia brought on by drinking two Monster energy drinks that was the cause of death, and the Ehlers-Danlos syndrome was just an added complication.

Now, on the heels of that report, come reports that the U.S. Food and Drug Administration is investigating this case, and also that the caffeine levels in energy drinks are under-reported on labels and that they can vary from can to can, sometimes containing more than one serving's worth.

There have been so many studies done on caffeine over the years that you would probably need to ingest the amounts they say are dangerous in order to read even a fraction of them. What is a dangerous level though?

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According to a Popular Science article, the editor-in-chief of The Journal of Caffeine Research (yup, it gets its own journal), Jack James, says that it takes roughly 10 grams of caffeine to cause an overdose in the average adult.

To work with a truly Canadian source for illustration — according to Tim Horton's, a 20 oz (Large) cup of their coffee has 200 mg of caffeine, so you would need to drink 50 cups to get a 10 gram dose. You can reduce that to 'only' 46 cups if you went with their newer Extra Large (24 oz) size, which has 240 mg of caffeine — apparently the same amount as a Monster energy drink. For comparison, a 355 ml can of Coca Cola only has between 36-46 mg of caffeine, so you'd need to drink around 250 cans to get up to 10 grams of caffeine. Of course, you'd need to drink all of that coffee, energy drink or soft drink fast enough that all the caffeine is in your system at once. A daunting task.

Still, it seems that there's still no consensus in the medical community about how much caffeine it takes to kill someone.

A 2005 report, regarding two cases of caffeine-overdose, with rather unusual circumstances, stated that it only requires only 5 grams to suffer a fatal caffeine overdose. That's still 25 of those large cups of coffee. Of course, knowing your general health, including any medical conditions you might be suffering from — especially those that would affect the condition of your heart and circulatory system — would certainly help determine how 'average' you are.

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Most sources, including Health Canada, advise that ingesting more than 400 mg of caffeine, for an average adult, is a bad idea. For children, the recommended limits are significantly lower, from 85 mg/day for a child 10-12 years, down to 45 mg/day for a child aged 4-6 years.

How does your daily caffeine intake compare to that? How many cups of coffee, or energy drink, or caffeinated soft drink has it been for you so far today and how many will you likely drink before the day is over?

Just some caffeinated beverage for thought.