German coco nut

Death By Coconut: A Story Of Food Obsession Gone Too Far : The Salt : NPR

Born in Nuremberg in 1875, August Engelhardt was among the disaffected youngsters drawn to the back-to-nature Lebensreform (Life Reform) movement sweeping through Germany and Switzerland at the time. Its proponents yearned after an unspoiled Eden where people ate
vegetables and raw food.

Engelhardt was especially taken by Gustav Schlickeysen's 1877 dietary treatise, Fruit and Bread: A Scientific Diet. Influenced by Darwinism, the book claimed that since the natural food of apes was uncooked food and grain, that was also "the proper food for man."

Engelhardt  took it even further: For him, even bread and fruit were tainted. In his mind, the only immaculate and mystical fleshpot was the coconut, with its snowy white meat and translucent water.

In 1898, he and fellow vegetarian August Bethmann laid out their vision in a pamphlet called A Carefree Future: The New Gospel. As the pamphlet's grandiose subtitle makes plain, Engelhardt's ambitions of a Coconut Camelot, with himself as a nude King Arthur, were driven by much more than dietary compulsions: His was a spiritual quest.

"He believed that since the coconut grew high up in the tree, closest to God and closest to the sun, it was godlike," says Kracht. "And since it had hair and looked like a human head, he thought it came closest to being a man. According to his rather crackpot theory, to be a  cocovore was to be a theophage — or eater of God."

 So he goes to an island in New Guinea with a coconut plantation, 15 young Germans join him, they die or catch malaria (which Engelhart claimed wouldn't happen because of the power of the coconut) and his cult ends.   Engelhardt himself dies at 44 as a skinny and very unhealthy man.

Now if only it had been parsnips, on the other hand....