Sorry, 'The Last of Us' fans — cannibalism just isn't that nutritious, according to a human evolution researcher

• Humans aren't a very good food source, according to a human evolution researcher.
• Cannibalism as shown in 'The Last of Us' wouldn't be a smart survival strategy, he said.

Fans of the post-apocalyptic drama "The Last of Us" came face-to-face with the moral quandary of eating flesh in episode eight, which depicts a group of survivors secretly killing and consuming unwary travelers to keep themselves alive.

But beyond the ethical problems cannibalism may pose, dining on other people, especially after covertly murdering and butchering them, just isn't a very viable diet strategy, said James Cole, principal lecturer in archaeology at the University of Brighton and the author of a detailed rundown on the caloric value of cannibalism.

"There's nothing particularly nutritious about us," he told Insider. "Compared to other animals, we're not an efficient food source because we're not a very big animal. You'd get much more protein and fat from wild game."

Preying on your peers also has significantly higher risks than stalking animals, since you typically don't have to worry about deer or boar packing a firearm, for instance, and they're less likely to outwit you.

"A person isn't going to be a passive victim. They'll likely fight back," Cole said.

The archaeological record does show some examples of early humans (and human relatives like Neanderthals) cannibalizing outsiders, although we don't know if motives were social, opportunistic, or something else.

As a proactive tactic for sustaining a community, cannibalism doesn't make much sense, according to Cole.

"For a long-term food strategy, you're much better off raising pigs or cows. They just give you a bigger return from a calorie perspective," he said.

A human body provides about 32,000 to 125,000 calories, depending on which parts you eat

Cole's initial interest in nutritional cannibalism was to help him demonstrate that Paleolithic cannibals may have had cultural, not dietary, reasons for eating each other. To this end, he wanted to show that humans were relatively unattractive food choices in the face of other hunting options like bison or deer. He calculated roughly how many calories a human body could provide using body composition data on four male adults from previous research from the 1950s, since obtaining new data would be ethically and logistically difficult.

The average muscle mass of an adult man would provide 32,375 calories worth of protein, Cole calculated. That's enough to feed a group of 25 adults for half a day. In comparison, a cow would feed the same group for 3 days, and a bison for 10 days.

At that rate, you'd need to consistently hunt more than a dozen people a week to keep everyone fed.

"It might be the occasional short-term opportunity if someone in your group died and you didn't need to go out hunting that day, but not a regular sustenance vehicle, particularly in a post-apocalyptic world where conditions are presumably very tough and harsh," Cole said.

But your dining options aren't limited to muscle, and historically, cannibals have also taken advantage of organs like the heart, liver, and kidneys, fat tissue, and even bones. You could consume as many as 125,000 calories per human body this way, and slightly more if you wanted to wring every last bit of nutrients out of the human body, including skin and teeth, according to Cole's calculations.

Eating nose-to-tail on a human does come with some additional safety concerns, though — neurodegenerative conditions like Creutzfeldt-Jakob (otherwise known as Mad Cow) disease, can be contracted by consuming diseased brains, for example.

The post-apocalyptic wasteland environment would also reduce the potential nutritional benefits of human prey even more, according to Cole.

"In a scenario where your ability to feed yourself is sporadic, and the quality of that food is sporadic, that will impact your fat reserves and muscle density," he said.

If circumstances are dire enough that cannibalism becomes a matter of life or death, his calculations did reveal a clear winner in the body part you should dig into first. The thighs have the most promising reserves of fat and muscle tissue, about 13,350 calories worth, combined.

But Cole doesn't recommend it, overall.

'Probably only engage in that activity if it's a question of survival, otherwise just leave each other alone," he said.