Urumiit 

"The droppings are collected when they have dried out during the winter months (fresh droppings in the summer are thought to be unpleasant to eat), a time in which food sources are scarce, especially on land, so the pre-digested willow and birch plant matter in ptarmigan scat provides a much needed source of nutrition in a harsh environment. One ptarmigan may defecate as many as 50 times in one spot, so urumiit is very plentiful and easy to gather. The pellet-shaped droppings are generally cooked in rancidified seal fat before eating; sometimes mixed with seal or ptarmigan meat or blood.  Historically in some areas, the meat cooked with urumiit is prepared by being pre-chewed by the women of a household. The smell of cooked urumiit in rancid fat has been compared to that of Gorgonzola cheese. It has been cited as a dish which non-Inuit are particularly likely to find disgusting, and as an example of how much taste in food can vary between cultural contexts.

• There are also teas and coffees that are considered delicacies that are first "processed" by being fed to an animal first before using. Some of these include Black Ivory Coffee from Thailand where coffee beans are fed to elephants before being collected from their feces. Kopi luwak or civet coffee uses the same process but with Civets not elephants. There are also tea plants that are only fertilized using Panda dung which is supposed to influence the flavor of the tea leaves.

• There's also a mortifying cheese called casu martzu from Sardinia where a cheese is "fermented" with the maggots of the cheese fly, which lives in the cheese and defecates which influences the cheese's flavor. This cheese is super dangerous to consume if the larvae are ingested because they can take up residence in your intestines.

• Some traditional medicines call for animal feces and urine to be used as treatments. The Beadouin use camel poop as a way to treat dysentery but there is only anecdotal evidence that this works.

• Western medicine used to use tasting urine or feces as a way to diagnose patients. Sweet urine is a hallmark of diabetes. In modern Western medicine, there is also a way to transplant fecal matter from a healthy individual to one that is not healthy, sometimes by ingesting a caspule with poop in it. THIS IS NOT A CURE ALL AND SHOULD NOT JUST BE DONE BECAUSE YOU SEE IT ONLINE. PLEASE FOR THE LOVE OF GOD. There is evidence to show that these fecal transplants can be helpful for several different chronic illnesses such as Fecal Transplant: What It Is, What It Treats, Procedure & Risks (clevelandclinic.org)

• A cult in Thailand ate the feces, urine, skin flakes, cigarette butts and saliva. The cult, in Chaiyaphum province would eat these … items from their holy man Tawee Nanla, as they believed it would be healing for them. The cult had generally unsafe food practices and had highly unsafe amount of mold and there were dead bodies….

• People also engage in autocorpophagy or eating of poop from humans. While "night soil" has long been a source of fertilizer for plants, some humans skip the veg and go straight for the poop. There are two reasons why people eat poop. One is kink. The other is mental illness, as it's generally a sign of schizophrenia, pica etc. It's not safe to eat your own poop. Please don't do it.

Why do we say, "eat shit" and what is a "shit eating grin"? 

Complete Source List

https://en.wikipedia.org/wiki/Coprophagia

https://en.wikipedia.org/wiki/Urumiit

https://en.wikipedia.org/wiki/Kopi_luwak 

https://en.wikipedia.org/wiki/Black_Ivory_Coffee 

https://en.wikipedia.org/wiki/Casu_martzu   

https://my.clevelandclinic.org/health/treatments/25202-fecal-transplant 

https://www.vice.com/en/article/n7n8ed/religious-cult-eats-poop

https://crossidiomas.com/eat-shit/

https://digitalcultures.net/slang/shit-eating-grin/