Caffeine 101

To all students returning to our campuses, and to anyone else who is thinking about increasing their caffeine intake, I offer this info about caffeine toxicity from DSM4. "Symptoms that can appear following the ingestion of as little as 100 mg of caffeine per day include restlessness, nervousness, excitement, insomnia, flushed face, diuresis, and gastrointestinal complaints."

What if you've been marinating in caffeine? "Symptoms that generally appear at levels of more than one gram per day include muscle twitching, rambling flow of thoughts and speech, tachycardia or cardiac arrhythmia, periods of inexhaustibility, and psychomotor agitation."

So, how much caffeine are you ingesting? The Center for Science in the Public Interest has tables here and here listing approximate, "typical" caffeine content of some beverages. Tolerance develops with chronic use, but higher-than-usual caffeine intake can cause problems. (Thus, one of our first questions to anyone suffering from anxiety: how much caffeine is on board?)