The year is 2018. Assume a species that looks near-exactly like humans. The only difference is diet. Instead of meat or vegetation, people consume feces; mainly from animals raised for the task (mammals). However, I feel that I am coming up short on the list of major and minor differences to society.

  1. Double-standard of clean (food is food, but dust and old food need to be cleaned up).
  2. Obviously hardened immune system.
  3. Never learned how to hunt, just gather and herd animals.
  4. Famine may no longer be a possibility (abundance).
  5. Dieting by only re-eating own stool (lack of nutritional value).
  6. Just out of principal, eating other people's stool is only in emergency situations.
  7. Factory farms MAY be worse (kept in racks, no need to move about).
  8. Food would "spoil" faster unless completely frozen.

What else am I missing? Any visible misconceptions?

  • 1
    $\begingroup$ getting enough calories from feces to power something as energetically expensive as a brain is highly unlikely. human eat some of the most calorie rich foods in existence while feces is among the most poor. $\endgroup$
    – John
    Commented Feb 15, 2018 at 22:04
  • $\begingroup$ Too broad and very unlikely. Herbivores didn't develop intelligence because: how hard is it to sneak up on a blade of grass? Your food source brings a similar problem. $\endgroup$
    – ShadoCat
    Commented Feb 16, 2018 at 0:17

1 Answer 1


Feces is just another product of domestic animals.

There are people who live almost entirely on animals and animal products. The Masai live on milk, meat and blood. Feces is an animal product like any other. Unless you want to spend extra time wriggling in gleeful disgust that it is feces you can think of these animals like dairy animals.

1. Providing for animals. The animals which produced suitable human food would themselves need to be provided for. You can herd the animals from pasture to pasture, as pastoralists like the Masai do. You can have agriculture for the purpose of feeding your domestic food animals, as developed countries do.

2. You would need special feces to feed humans. Feces has had much of the original food energy stripped by the animal producing it. There may be vitamins in feces provided by intestinal flora, but you will have to make up some scheme by which enough nutrients pass through these food animals to sustain humans. Or possibly via which things indigestible by humans and rendered digestible by the passage through the animal. I was thinking about a world where yeast would be the main protein - very yeasty beer was my idea, but yeasty feces might be an option. A feces full of yeast and micro-organisms might be energy dense enough to sustain humans. Or perhaps the animal eats mostly cellulose because that is what is available, and the feces has undergone processing in several stages by the animal and then its commensal flora such that the sugars are available for our own digestion.

Listed issues

  1. Hardened immune system - our current one is fine for this. Stomach acid is awesome. Our mucosal barriers are awesome. Much more than we need for McDonalds.

  2. Gather and herd animals is fine if that gets the job done. Think dairy.

  3. There is only abundance feces food if your food animals have abundant fodder.

  4. Re-eating own stool - that is silly. Human feces is not adequate food.

  5. Other peoples stool - also silly and I think betrays the real motiviations of this post!\

  6. Factory farms - again the analogy is dairy farms.

  7. "Spoil faster" I am not sure why. The endogenous microbes would probably fend off intruders for some time.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .