I recall in uni reading about a ship of pirates (yes, in the Caribbean, this story published pre-1994, so nothing about the movies) that landed on a small island with only a ton (who knows how many tons) of sugar destined for America, and plenty of Carribean-distilled barrels of rum. After about a week of ONLY eating sugar and drinking rum, over half the crew had died. Science shows us that a water-only fast is survivable for over a month! (Now, maybe they had no water to drink, and heat stroke is dangerous; in any event, the white sugar and rum appear to have contributed to if not outright caused their deaths).