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View count:1,920
Likes:191
Dislikes:7
Comments:23
Duration:12:24
Uploaded:2019-05-05
Last sync:2019-05-05 17:10
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We've all got bad habits that we might feel a little bad about, but we're here to tell you stop feeling guilty! Kind of.

Hosted by: Hank Green

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Sources:

(Knuckle Cracking)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1004074/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1129752/
https://onlinelibrary.wiley.com/doi/epdf/10.1002/1529-0131%28199805%2941%3A5%3C949%3A%3AAID-ART36%3E3.0.CO%3B2-3
https://link.springer.com/article/10.1007/s11999-016-5215-3
https://press.rsna.org/timssnet/media/pressreleases/14_pr_target.cfm?ID=1851
https://www.loc.gov/rr/scitech/mysteries/joint.html
https://www.aurorahealthcare.org/services/orthopedics/conditions/crepitus#Overview

(Gum Chewing)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4449949/
https://www.tandfonline.com/doi/abs/10.1179/147683010X12611460763526?src=recsys
https://www.ncbi.nlm.nih.gov/pubmed/11145462/
https://www.ncbi.nlm.nih.gov/pubmed/23375117/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4449948/
https://www.ncbi.nlm.nih.gov/pubmed/22747775

(Swearing)
https://www.sciencedirect.com/science/article/pii/S038800011400151X
https://www.emeraldinsight.com/doi/abs/10.1108/JMP-04-2016-0102
https://www.academia.edu/29725191/Frankly_we_do_give_a_damn_The_relationship_between_profanity_and_honesty
https://journals.lww.com/neuroreport/Abstract/2009/08050/Swearing_as_a_response_to_pain.4.aspx
https://www.wired.com/story/the-science-of-why-swearing-physically-reduces-pain/

(Nail biting)
https://pediatrics.aappublications.org/content/138/2/e20160443?sso=1&sso_redirect_count=1&nfstatus=401&nftoken=00000000-0000-0000-0000-000000000000&nfstatusdescription=ERROR%3A%20No%20local%20token
https://www.sciencedirect.com/science/article/pii/S0363502387802174
https://www.researchgate.net/publication/284275097_The_human_microbiome_asthma_and_allergy https://www.elitedaily.com/life/culture/positive-side-nail-biting/749315
https://www.mayoclinic.org/healthy-lifestyle/adult-health/expert-answers/nail-biting/faq-20058548
https://www.baos.org.uk/resources/Temporomandibular(Jaw)JointProblems.pdf
https://danieladental.com/tmj-treatment/

(Complaining)
https://journals.aom.org/doi/abs/10.5465/256708
https://onlinelibrary.wiley.com/doi/abs/10.1002/jclp.10095
https://psycnet.apa.org/record/2002-08580-004
https://www.psychologytoday.com/gb/blog/the-couch/201410/whats-the-best-way-deal-help-rejecting-complainers
https://digest.bps.org.uk/2017/03/23/workplace-venting-makes-it-harder-to-bounce-back-from-bad-experiences/
https://www.cambridge.org/core/journals/child-psychology-and-psychiatry-review/article/cognitive-behaviour-therapy-in-childhood-depression/394443127404D965706CAE582EC9A054

IMAGES

https://www.youtube.com/watch?v=_ZNENkkf5Uw

https://en.wikipedia.org/wiki/Metacarpophalangeal_joint#/media/File:Grant_1962_104_MCP.png

https://commons.wikimedia.org/wiki/File:Staphylococcus_aureus_SEM.jpg#/media/File:Staphylococcus_aureus_SEM.jpg
Thanks to Skillshare for supporting this episode of SciShow. [♪ INTRO].

We’ve all got bad habits. It’s kinda part of the whole ‘being human’ package.

We might even feel kind of bad about not breaking those habits sometimes. Well, I’m here to tell you to stop feeling guilty!... Kind of. it turns out some of the things we rag on ourselves for doing might not be so bad after all.

Scientists have found surprising upsides to things like swearing and biting your nails. So let’s take a closer look at the research behind five so-called “bad” habits. If you’re one of those people that just has to crack their knuckles before you get down to business, you might have been told to stop so you don’t wreck your fingers.

A whole lot of people believe that cracking your knuckles damages your joints, and that can lead to arthritis. But that isnot true! That factoid was based on a study from 1990 that mistakenly concluded that knuckle cracking resulted in ‘functional hand impairment’.

That research was criticized for not being controlled well, meaning the conclusions couldn’t be trusted. But, it did manage to kick off a whole lot of follow up studies that showed us that, actually, it doesn’t hurt your joints at all. For example, studies have found older people with a history of knuckle cracking don’t have any more knuckle degeneration than those that don’t.

One doctor even cracked just one hand for five decades —which, can I just say, is some serious commitment to science and also will power, once I star, I have to do them all— and there ended up being no differences between his hands in terms of pain or function. The only effect cracking seems to have is that it opens up the joint’s range of motion a little. The sound might make you think something is being forced back into place, so it’s kind of understandable that people might think a tendon or bone or something is physically snapping.

But, that’s not what’s happening. Ultrasounds of the base joint of fingers—known as the metacarpophalangeal joint, or MPJ— have showed that when a joint cracks, a bubble rapidly forms and then collapses in the synovial fluid, the stuff between the bones that keeps them lubricated. That bubble popping — or, maybe the creation of the bubble, we’re not 100% sure — is what makes the sound.

So crack away! Unless it’s causing you phsyical pain. In which case, don’t do that.

Even if cracking itself doesn’t cause damage, damaged joints can start to pop and hurt. So if something’s painful, go get that checked out. Gum chewing can also get a bad rap.

People say it’s bad for your teeth, and well, frankly, it’s just annoying if a person does it loudly. No one wants to hear **chewing noises** from the next cubicle over. And you’re just like I have to be here for 8 more hours!

But it turns out chewing is kind of awesome for you— especially if you’re trying to be productive. Studies have found that the act of chewing gum is associated with enhanced attention and work performance. Which is maybe why we do it, because otherwise, why do we do this?

And weirdly enough, that research didn’t just find that chewing gum gives you an attentional boost. The speed and force with which you chew affects just how much benefit you get. Chewing too fast seems to slow your reaction speed a little —slow but steady is the key.

And chewing relatively hard is associated with faster information processing. Studies have also found that things like cortisol levels and heart rate increase when you’re chewing, and that in turn supports the idea that the act of chewing gum makes people more alert. Some researchers think these effects could be attributed to minty flavors.

It’s possible they’re just super refreshing and wake people up, kind of like a mini cold shower for your mouth. But that’s definitely not the whole story. Some studies have found that things like quicker reaction times in gum chewers, even if the gum they’re chewing is flavorless.

And in one study with flavorless gum, brain scans showed increased activation in the anterior cingulate cortex and left frontal gyrus of the chewers — areas that are related to attention and motor control. This suggests that chewing really does alter your brain’s ability to focus. As for why chewing has this effect, well.

We don’t know. There are theories — like, that it’s causing increased blood flow to the brain, or that the action itself is just super soothing and stress relieving. But however it works, make sure to chew sugar-free gum.

Because those naysayers are right that chewing gum can harm your teeth if it’s loaded with bacteria food. Sugar-free gum doesn’t cause the same damage, and has even been shown to reduce plaque— as long as long as you are brushing regularly, as well. You should not think that chewing is a replacement for brushing your teeth and flossing.

If the words that escape your lips when you stub your toe would make your mom clutch her pearls,. I’ve got some good news for you! Swearing a lot might indicate some nice things about you, and it will probably help with that owie.

You might think people who swear just don’t have better words to use, but research has shown that potty mouths actually have larger vocabularies. That is, except when those swears consist mostly of sexist slurs. Turns out female-sex-related slurs have transitioned into our everyday lexicon in recent decades.

That means people that reach for those particular curses don’t have to dig as deep into their vocabulary, so saying them doesn’t signal verbal ability. Shocker, I know. Actually surprisingly, though, researchers have found that dropping a couple of choice phrases at the right moment might provide all sorts of benefits from stress relief to improved social relations.

A 2017 study published in the Journal of Managerial Psychology reported wide use of swears in the workplace by lawyers, medical professionals and business executives. When interviewed, their 52 participants stated that cursing was useful in a wide range of settings, like to indicate you’re close with your colleagues, and to show that you’re passionate. And this idea that swearing helps cement bonds between people is especially intriguing since psychologists have also found that swearing correlates with measures of honesty.

Think about it — if you’re being honest about the sheer intensity of your feelings, like when you think something is super freaking remarkable, you may be more ready to reach for an f-bomb than someone who’s not being genuine. So it’s possible that part of the reason swearing promotes bonding is because it signals that you’re being real with the person. That same 2017 study also found swearing provided some stress relief to tense working conditions — introducing a fun, less intense atmosphere.

And on top of all of that, studies have shown cursing can actually dull pain and make you more resistant. Like, people can keep their hands in icy water for longer, or squeeze a joystick harder when they’re swearing than when they’re saying other, non-taboo words. There’s no complete consensus on why this effect happens, but some evidence suggests that saying bad words activates your fight or flight response, and therefore, triggers a flood of chemicals that help act tougher up in scary situations.

So, it seems swearing has its benefits, even at work. But still, maybe don’t risk it while the boss is around, unless you know they’re cool with it. Also it’s probably best if it’s an occasional thing, rather than every other word.

A lot of people don’t even realize when they’re biting their nails. It becomes so ingrained because they started doing it as a kid. And it turns out developing that habit in childhood actually has health advantages.

Research has shown that people who chewed their nails and/or sucked their thumb as kids are less likely to develop allergies in their teens, and even in their 30s! That’s because there’s a lot of... Well, grossness, on your hands.

Especially under your fingernails. In addition to flecks of whatever you’ve touched, your grubby fingers can sport mold, yeast, Staphylococcus epidermidis... things you probably wouldn’t choose to eat if it was on a menu. But that’s kind of a good thing, at least from an immunology perspective.

Scientists have found that exposure to such things in small amounts can help keep your immune system from developing an allergic response to them. Basically, if your body has seen it all before and knows these common things won’t kill you, it doesn’t freak out when it sees them later on. And since a little childhood finger sucking or nail nibbling means you ingest more of this stuff in your younger years, you don’t end up with as many allergies when you grow up.

If you’re older, though, sorry to break it to you, but you’re probably not getting all that much in the way of benefits from your bad habit. In fact, doctors recommend you don’t chew your nails at all as an adult. All that nibbling can cause cracks in the skin, which could then let harmful bacteria in, putting you at a greater risk for infection.

Studies have also found that the positions you have to wrangle your jaw into to gnaw on your nails can even lead to lasting dysfunction in the temporomandibular joint, or TMJ. And that comes with a whole host of not-so-fun symptoms, like jaw pain, popping while chewing, headaches and difficulty opening wide. So adults, by all means keep your nails trimmed, but just, maybe, not with your teeth.

Listening to someone complain all day is no fun, and more often than not, no good for your mood. But it can be the opposite if you’re the one complaining. Having a good rant can lead to catharsis — basically, the letting out of frustrations and stress, lifting your mood.

It can even make others like you more, in certain circumstances. A study from 2002 suggests that airing grievances with a person can make your bond seem closer and cause them to re-evaluate how close you are. In a good way, that is.

The study found that both the complainer and the person they complained about reported liking each other more after complaints were brought up up face to face when compared with instances where complaints had been shared with a third party. The thing is, while complaining does have some benefits, it’s more of an art than a science. People aren’t always going to respond to griping with positivity.

It may even push people away, especially if you become a help-rejecting complainer. I mean, I get it. Sometimes you just want to gripe and have people tell you it sucks.

And that’s totally understandable. But, many people find it hard to sympathize with someone who refuses help for their troubles, so after a while it might mean that your complaints start to fall on deaf ears. Complaining can also sometimes function as rumination.

That’s when you focus on negative thoughts and just can’t seem to stop turning over the same sucky ideas over and over. It’s a real downer, to say the least. And some research has found that giving voice to our frustrations by complaining can give them a second wind, dragging us back down into negative emotions, whereas just taking it in your stride and moving on means you never have to think of it again.

That said, don’t let that convince you to bottle it all up. Letting out our negative emotions is healthy, and often recommended by therapists. There you have it—five bad habits that aren’t always bad.

I mean, sure, maybe not all your habits are great for you all the time. And yeah, some habits are kinda gross. Or irritating.

Or put mold inside your mouth. But does that stop us from doing those things? No, not really.

Of course, if you want to change your habits anyway, more power to ya! Just know that I’m agoing to keep cracking my knuckles. Maybe you want to establish habits with a little more weight to them.

Maybe you want to try your hand at being more productive, and managing your time more efficiently. Skillshare has lots of courses on productivity and project management that might be able to help you out. Skillshare is an online learning community for creative folks, with more than 25,000 classes in everything from photography and illustration to business.

For example, in his course on “Productivity Habits that Stick,” Mike Varney teaches you some tips for how to divide up your time by different themes, to help you choose when to do certain tasks and get everything done more efficiently. More than 7 million creators are learning with Skillshare. And the first 500 SciShow subscribers to use the link in the description will get a 2 month free trial, so you can take it for a test drive and see if it’s right for you. [ OUTRO ].