Cannibalism in Brazil engraving by Theodor de Bry to illustrate Hans Staden's account of his captivity in 1557. Wellcome Collection. CC BY 4.0

Cannibalism is seen as one of the darkest taboos in many cultures. But beyond the social stigma of eating fellow humans, there's a strange (and fascinating) danger that comes with cannibalism.

In 1961, a young Australian medical researcher called Michael Alpers headed to the Eastern Highlands of Papua New Guinea, inspired to merge his two passions of medicine and adventure. Here, he began to investigate a mysterious condition suffered by the Fore people, a scarcely touched tribe that lived deep in the mountains and practiced cannibalism.

“The body was eaten out of love as well as for gastronomic appreciation,” Alpers wrote in one of his academic texts about the Fore people.

They called this condition "kuru". Every year, kuru would kill up to 200 people of the tribe, sometimes in startling circumstances. Starting with tremors and an impaired ability to work, sufferers go on to develop a total loss of bodily function, depression, and often emotional instability, sometimes exhibiting itself as hysterical laughter. When word of the disease spread to the west, the media sensationally dubbed it “laughing death”.

The Fore people believed it was a terrible curse, but Alpers wanted to find a more scientific explanation to this mystery. Curiously, the condition did not appear to be caused by a virus, bacteria, fungus, or parasite. Equally as strange, it was only women and children who fell sick.

This made the researchers begin to wonder: Perhaps it had something to do with the Fore’s funerary ritual of cannibalism. The practice involved only the women and children eating the brains, while the men would just eat the flesh.

During an interview for Cosmos Magazine in April 2016, Alpers explained: “The argument for cannibalism – and I don’t use that term anymore, but it was used then – was compelling. Everything fitted.”