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The chances of a regular soft drink being a little over 1.5 liters or three pints fatal are very, very unlikely, I mean, surprisingly impossible. Typically, this is because you have bacteria that have moved from the normal gastrointestinal tract to places where they are not supposed to be, in this case, in the lining of the small intestine, "said Nathan Davis, a biochemist professor at University College London, the Daily Mail reported.He also made it clear that drinking Coca-Cola in large quantities, as well as an underlying condition, could be the cause of his death.