Tarrare's freak-show antics finally came to an end in 1792, when the War of the First Coalition began and, like other young men his age, he signed up to join the French Revolutionary Army.
But military rations for soldiers were hardly enough to keep Tarrare's hunger at bay. The poor guy would finish his meal, then lick up the scraps left behind by other soldiers, rummaging through the garbage in search of more. With too little to satiate him, he fell into a fit of extreme exhaustion and was sent to the hospital. That's when he met Dr. Pierre-François Percy, a renowned physician who would follow his saga, off and on, for the rest of Tarrare's miserable life.
Percy, along with colleague Dr. M. Courville, gave Tarrare four rations to see if that could satisfy his appetite. When that failed, Percy and Courville decided to see just how much he could eat. So they served him a meal for 15 German laborers, including two huge meat pies and 4 gallons (15 liters) of milk, which he devoured within minutes.
Flabbergasted at the ease with which Tarrare consumed the meal, the doctors took their experiment further. They handed him a live cat, which he disemboweled with his teeth before sucking its blood, eating all but the bones, and then vomiting out the fur, as archived in the Anomalies and Curiosities of Medicine.
They also fed him an assortment of other animals including snakes, lizards and live puppies. And, on at least one occasion, they handed him a live eel, which he swallowed whole without chewing.
Then suddenly, they had an idea. Could Tarrare's disturbing talent be used to the French army's advantage in the war against Prussia?