Sometimes weird things come through my Google searches based on suggestions. I had been doing some safety searches for a friend when “LD 50 Caffeine” came up in the suggestion box, so I clicked on the suggestion.
Death from caffeine ingestion appears to be rare, and most commonly caused by an intentional overdose of medications. In 2016, 3702 caffeine-related exposures were reported to Poison Control Centers in the United States, of which 846 required treatment at a medical facility, and 16 had a major outcome; and several caffeine-related deaths are reported in case studies. The LD50 of caffeine in humans is dependent on individual sensitivity, but is estimated to be 150–200 milligrams per kilogram (2.2 lb) of body mass (75–100 cups of coffee for a 70 kg (150 lb) adult).[failed verification] There are cases where doses as low as 57 milligrams per kilogram have been fatal. A number of fatalities have been caused by overdoses of readily available powdered caffeine supplements, for which the estimated lethal amount is less than a tablespoon. The lethal dose is lower in individuals whose ability to metabolize caffeine is impaired due to genetics or chronic liver disease. A death was reported in a man with liver cirrhosis who overdosed on caffeinated mints.
That means by the time I get close to even a harmful dose of Vitamin C2 my kidneys are already flushing it out of my 190 pound (86 Kg) body. I might damage my kidneys, but I wouldn’t be in mortal peril from drinking as much coffee as I could chug. My liver has been tested several times during drug evaluations, and as the family joke goes when I die they are going to have to beat my liver to death with a stick. I have several now-deceased relatives who were legendary drinkers with high alcohol tolerance, but who never-the-less not alcoholics as they could go months without drinking to no obvious ill effects, between drinking sessions that would have killed others from alcohol poisoning, also with no obvious ill effects. I have never seen any need to emulate their feats, so my own tolerance is still in question. Mind you these were all relatives on my father’s side, mostly related via my grandfather.
But this is secondary to my coffee consumption, which is currently running about a liter per day. At that rate I will live forever as far as dangerous amounts of caffeine are concerned.