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Scientists Test the 5-Second Rule

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Can we really protect ourselves from germs by snapping up our fallen snacks within five seconds? Two scientists at Rutgers have tested the rule and say the answer is a resounding “…sort of.” They published their findings in the journal Applied and Environmental Microbiology.

The five-second rule, for those of you not familiar (what, did you skip elementary school?), states that food dropped on the floor is still safe to eat as long as you pick it up within five seconds. The origins of the rule are murky, but study co-author Donald W. Schaffner attributes it to Genghis Khan. Speaking to the New York Times, Schaffner said the legendary warlord once claimed that food was safe to eat for a full five hours after it had fallen to the ground. As centuries passed and we learned about germs, that five-hour estimate became a lot more conservative.

Five hours, five seconds—does timing really matter? Schaffner and his co-author Robyn C. Miranda decided to find out. They dropped four foods (watermelon, bread, bread with butter, and strawberry gummies) on four different surfaces (stainless steel, ceramic tile, wood, and indoor/outdoor carpet) for four different periods of time (less than one, five, 30, and 300 seconds) and measured the amount of bacteria each sample collected. They were looking specifically at the bacterium Enterobacter aerogenes, which causes all kinds of nasty infections.

They found that there might be something to that five-second rule after all, or at least the idea of retrieving downed morsels as soon as possible. The longer the food samples sat on the ground, the more bacteria they attracted. But bacteria did manage to find them all, even the one- and five-second samples. Even the speediest hand couldn’t snatch a gummy from the jaws of instantaneous bacterial invasion.

Interestingly, the authors say, time may be the least important part of the equation. Two other components had a huge impact on a sample’s vulnerability.

The first variable is the type of food, specifically its moisture content. It’s biology 101: Bacteria love water. It’s why your dish sponge starts to reek if you don’t regularly squeeze it out. It’s also why bacteria swarmed the wet watermelon while paying little attention to the gummy strawberries.

The other thing that made a difference was the surface onto which the food had fallen. Tile and stainless steel were the grossest, while carpet was relatively clean, but each sample’s bacterial content was ultimately determined by interactions between all three factors (time, food, and surface).

Now, for the five-second question: Does any of this matter? Should we give up on every Dorito we ever drop again? That’s really up to you. Honestly, there’s already bacteria all over everything you will ever touch (not to mention the teeming bacterial ecosystem that lives in your mouth), and most of it is completely harmless.

“I’ve eaten food off the floor,” Schaffner told the Times. Still, he recommends considering the water content of your lost bite. “If I were to drop a piece of watermelon on my relatively clean kitchen floor, I’m telling you, man, it’s going in the compost."

[h/t The New York Times]

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

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Why You Get Diarrhea When You're Hungover
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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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