A slim, hundred-pound teenager devours a meal meant for fifteen laborers, including four gallons of milk, then collapses with his stomach stretched like a balloon. This deep dive examines Tarrare, an 18th-century Frenchman whose insatiable, uncontrollable hunger defied everything we understand about the human body, drawing on original medical papers and modern diagnostic theory.

We trace his tragic life from being exiled by his starving family to working as a sideshow performer, a failed military spy, and finally a human test subject for early clinical science. Along the way we explore what hyperthyroidism and a damaged hypothalamus might explain, and what they cannot.

• The metabolic puzzle of putting 100 pounds of meat into a 100-pound body that never gained weight
• His anatomy: a four-inch jaw span, skin loose enough to w ...