© Bill & Melinda Gates Foundation
© Bill & Melinda Gates Foundation

The Recipe for Fake Poop

© Bill & Melinda Gates Foundation
© Bill & Melinda Gates Foundation

Researchers around the world are working to reinvent the toilet, bringing toilets to the 2.5 billion people worldwide who don't have a safe place to relieve themselves. But there's a slightly gross problem—how do you test a toilet in a sanitary and, ahem, repeatable way?

Enter "fake poop," my preferred term for what scientists call "synthetic sludge simulant." Yes, this is a material meant to simulate fecal matter, and it has to have properties very similar to real fecal matter—minus all the pathogens, odors, and grossness. For this year's Reinvent the Toilet Fair, a new recipe was developed by the Pollution Research Group at the University of KwaZulu‐Natal, South Africa. Their recipe was inspired by a research paper on simulated fecal matter used to test space toilets ("Simulated Human Feces for Testing Human Waste Processing Technologies in Space Systems," SAE Technical Paper 2006-01-2180, 2006, doi:10.4271/2006-01-2180). The Pollution Research Group developed a series of recipes, finally settling on the ninth one. Here's the breakdown of what's in "Synthetic Sludge Recipe Number 9":

1. Instant Yeast

Plain old store-bought yeast packets you'd use to make bread.

2. Psyllium Husk

Seed husks that provide mucilage, described by Wikipedia as "a thick, gluey substance produced by nearly all plants and some microorganisms." You can often buy this in the bulk aisle at grocery stores.

3. Peanut Oil

Just what it says on the tin.

4. Miso Paste

The fermented seasoning used in many Japanese recipes. Available in packet form from grocery stores.

5. Polyethylene Glycol (PEG) 400

PEG is used in all sorts of applications (including skin creams and toothpastes), but if you've ever had a colonoscopy, you'll recognize it as that gloopy stuff you have to drink to, ahem, clear out your system. Well, technically, the colonoscopy prep material is PEG 3350, the number referring to the material's molecular weight as measured in daltons.

PEG 400 is actually available on Amazon, and it's an ingredient in many non-fake-poop products, including inkjet printer ink.

6. Inorganic Calcium Phosphate

Often used as a leavening agent in baking, Calcium phosphate is also used in some cheese products. If you're looking to follow the recipe exactly, you'll want to buy this from a chemical supply company.

7. Cellulose

The recipe calls for cotton linters, a byproduct of cotton harvesting and an ingredient in paper manufacturing. The recipe also includes plain old paper tissue, shredded.

8. Water

What's a recipe without a little water? (Actually, a lot of water -- see the mass numbers below.)

What it Looks Like

The resulting product was "very sticky," according to a person close to the matter. It reportedly has a "vinegar-yeasty smell." Let's just look at a photo of the fake poop being bottled and leave it at that:

Photo courtesy of The Bill & Melinda Gates Foundation.

Putting it Together

Here's the breakdown when it's all put together:

Ingredients % Wet Mass Mass for 1kg % Dry Mass
Instant yeast 7.3 72.80 32.49
Water 77.6 776.10 --
Psyllium 2.4 24.30 10.84
Peanut oil 3.9 38.80 17.31
Miso paste 2.4 24.30 10.84
PEG 2.7 27.20 12.14
Inorganic Calcium phosphate 2.4 24.30 10.84
Cellulose (half cotton linters/half shredded tissue) 1.2 12.40 5.53
Total Mass 100.0 100.20 100.00

This year's fake poop was manufactured by Unilever and donated to the Reinvent the Toilet Fair: India. Unilever also makes the toilet cleaner Domex, and is holding a Domex Toilet Academy aiming to build 24,000 toilets by 2015.

Fake urine, on the other hand, can be less complicated. If you're just testing fluid flow in a toilet, plain old water will work. (For applications involving chemistry, well, let's just say that's a whole different story.) Here's an image from the Reinvent the Toilet Fair showing a little fake urine going in the loo:

Photo courtesy of The Bill & Melinda Gates Foundation.

For a bit more fake poop fun, check out this TEDx Talk by Professor A.J. Johannes, who didn't use this recipe for his fake poop. He said, "Mashed potatoes, curiously enough, are very, very similar [to human feces]. I know, I know."

Can You Really Lose Weight by Pooping? It Depends on What You Eat

If you’re obsessed with either your scale or your bowel movements, you’ve probably wondered: How much of my weight is just poop? A teenage cousin of mine once spent an entire restaurant dinner arguing that he could lose up to 3 pounds if you just gave him a few minutes to sit on the toilet. As you might imagine, he was wrong. But not by that much, according to Thrillist, a site that’s been truly dominating the poop science beat lately.

You can indeed see the effects of a truly satisfying bowel movement reflected on your bathroom scale. (Wash your hands first, please.) But how much your feces weigh depends heavily on your diet. The more fiber you eat, the heavier your poop. Unfortunately, even the most impressive fecal achievement won't tip the scales much.

In 1992, researchers studying the effect of fiber intake on colon cancer risk wrote that the daily movements of poopers across the world could vary anywhere from 2.5 ounces to 1 pound. In their sample of 220 Brits, the median daily poop weighed around 3.7 ounces. A dietary intake of around 18 grams of dietary fiber a day typically resulted in a 5.3-ounce turd, which the researchers say is enough to lower the risk of bowel cancer.

A Western diet probably isn’t going to help you achieve your poop potential, mass-wise. According to one estimate, industrialized populations only eat about 15 grams of fiber per day thanks to processed foods. (Aside from ruining your bragging rights for biggest poop, this also wreaks havoc on your microbiome.) That's why those British poops observed in the study didn't even come close to 1 pound.

Poop isn’t the only thing passing through your digestive tract that has some volume to it. Surprisingly, your fabulous flatulence can be quantified, too, and it doesn’t even take a crazy-sensitive machine to do so. In a 1991 study, volunteers plied with baked beans were hooked up to plastic fart-capturing bags using rectal catheters. The researchers found that the average person farts around 24 ounces of gas a day. The average fart involved around 3 ounces of gas.

This doesn’t mean that either pooping or farting is a solid weight-loss strategy. If you’re hoping to slim down, losing a pound of poop won’t improve the way your jeans fit. Certainly your 24 ounces of gas won't. But to satisfy pure scientific curiosity, sure, break out that scale before and after you do your business. At least you'll be able to see if your fiber intake is up to snuff.

[h/t Thrillist]

Why You Get Diarrhea When You're Hungover

If your hangover mornings involve a lot of time sitting on the toilet, you're not alone. In addition to making you puke your guts out, drinking too much can also give you massive diarrhea the next day. Why? Thrillist talked to a gastroenterologist about the hangover poops, and found that it's a pretty common phenomenon, one caused by a combination of unusually fast-moving digestion.

When you drink, Urvish Shah told the site, alcohol increases what's called gut motility, the contractions that move food along your gastrointestinal tract. Combine this with the fact that booze inhibits vasopressin—the hormone that regulates water retention and prevents your kidneys from immediately dumping whatever liquid you drink into your bladder—and suddenly your guts have become a full-blown water slide.

All those cocktails take a fast-paced thrill ride down to your colon, where your gut bacteria throw a feast. The result is a bunch of gas and diarrhea you don't usually get when food and water are passing through your system a little more slowly. And because it's all rushing through you so fast, the colon isn't absorbing as much liquid as usual, giving you even more watery poops. If you haven't eaten, the extra acidity in your stomach from the booze can also irritate your stomach lining, causing—you guessed it—more diarrhea.

The more concentrated form of alcohol you drink, the worse it's going to be. If you really want to stay out of the bathroom the morning after that party, go ahead and take it easy on the shots. Because beer is so high in carbohydrates, though, Thrillist warns that that will cause gas and poop problems too as the bacteria in your gut start going to town on the undigested carbs that make it to your colon.

All in all, the only way to avoid a post-alcohol poop is to just stop drinking quite as much. Sorry, folks. If you want to rule Saturday night, you'll have to deal with the Sunday morning runs.

[h/t Thrillist]


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