The Psychology Behind Why Some People Won't Drink Recycled Water

The reasoning behind what grosses us out isn’t always rational. For instance, despite the fact that we can recycle sewage into completely clean, potable drinking water, even people in the most drought-prone regions just can’t get beyond the fact that it used to have poop in it. Why? Let MinuteEarth explain—with the help of animated turds—why disgust is so powerful. 

Still, not everyone finds the same things disgusting, or to the same degree. And what you find truly gross can impact more than just your opinions on drinking recycled water. In fact, a 2014 study found that political affiliation can be linked to how the brain responds to disgust: liberals had very different neural responses to gross images than conservatives did. 

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Scientists Think They Know What Causes Trypophobia

Picture a boat hull covered with barnacles, a dried lotus seed pod, milk bubbles on a latte, or a honeycomb. Images of these objects are harmless—unless you're one of the millions of people suffering from trypophobia. Then they're likely to induce intense disgust, nausea, and fear, and make your skin crawl.

Coined fairly recently, the term trypophobia describes the fear of clusters of holes. The phobia isn’t recognized by the Diagnostic and Statistical Manual of Mental Disorders, but its visibility on the internet suggests that for many, it’s very real. Now, scientists in the UK think they've pinpointed the evolutionary mechanism behind the reaction.

Tom Kupfer of the University of Kent and An T. D. Le of the University of Essex shared their findings in the journal Cognition and Emotion. According to their research, trypophobia evolved as a way to avoid infectious disease. Thousands of years ago, if you saw a person covered in boils or a body covered in flies, a natural aversion to the sight would have helped you avoid catching whatever they had.

But being disgusted by skin riddled with pathogens or parasites alone doesn't mean you're trypophobic; after all, keeping your distance from potential infection is smart. But trypophobia seems to misplace that reaction, as the authors write: "Trypophobia may be an exaggerated and overgeneralized version of this normally adaptive response."

Lotus pod.
Lotus seed pods are a common trigger of trypophobia.

This explanation is not entirely new, but until now little research has been done into whether it's accurate. To test their hypothesis, the scientists recruited 376 self-described trypophobes from online forums, and another 304 college students who didn't claim to have the affliction. Both groups were shown two sets of images: The first depicted clusters of circle-shaped marks on animals and human body parts (the "disease-relevant cluster images"); the second showed clusters of holes on inanimate objects like bricks and flower pods ("disease-irrelevant cluster images"). While both groups reported feeling repulsed by the first collection of photographs, only the trypophobes felt the same about the pictures that had nothing to do with infection.

Another takeaway from the study is that trypophobia is more related to sensations of disgust than fear. This sets it apart from more common phobias like arachnophobia (fear of spiders) or acrophobia (fear of heights). And you don't have to be trypophobic to be disgusted by a video of Suriname toadlets being born through holes in their mother's back. We can all be grossed out by that.

Disposable Sheets Allow College Kids to Avoid Laundry Forever

At college, many young people start to stretch their adult wings for the first time, learning how to be independent and take care of themselves without any hovering parents. Some things, however, are hard to adjust to—like figuring out how often to wash your sheets. Luckily, as Curbed recently highlighted, college students don’t need to worry about how they’re going to get clean sheets anymore. They can just buy one-use, disposable ones from Boston-based company Beantown Bedding, which sells sheet sets that never need to be washed. Just throw them in the compost bin and buy another set.

The company was founded by two women who, after sending their teens off to college, discovered that college kids are really terrible at doing their laundry. “As a result, they become the victims of a sickening accumulation of sweat, body oils, bacteria, germs, and dead skin cells which host millions of dust mites,” they write on the company website, blaming frequent student sickness on unwashed sheets. But laundering your bedding is a lot of work, they argue. “It didn’t take long for Kirsten and Joan to realize that washing and drying sheets just takes too much time.”

Do people typically wash their own sheets on vacation? And does it take an entire day?

The biodegradable one-use sheets—which the company also bills as a resource for hospitals and the hospitality industry—are made from eucalyptus wood pulp, but they still probably don't live up to the company's "eco-friendly" description. While the sheets may not need to go in the landfill, that doesn’t mean that manufacturing a ton of disposable sheets doesn’t require environmental resources.

Twin sheet sets start at $20, and yes, you can get a monthly subscription.

[h/t Curbed]

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