Spit: Everything You Never Wanted To Know

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Warning: May contain the “m-word”…
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↓ More info and sources below ↓
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References/further reading:
“Gulp” by Mary Roach: A great read about the odd science of the digestive system
amzn.to/1U4i2N7 (Public library: www.worldcat.org/oclc/811599508)
Carpenter, Guy H. "The secretion, components, and properties of saliva."Annual review of food science and technology 4 (2013): 267-276.
Perry, George H., et al. "Diet and the evolution of human amylase gene copy number variation." Nature genetics 39.10 (2007): 1256-1260.
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It’s Okay To Be Smart is written and hosted by Joe Hanson, Ph.D.
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[@loudrockacdc]

Saliva is protein? So will constantly swallowing my saliva lead to gainz?

[@ilikemetal2910]

Yes

[@i_am_superuser]

and constantly spitting saliva will make you lose weight

[@iamjesus6282]

100 likes :)

[@onixsii7708]

and the biceps shrinks from salat

[@FreaackyFreaky]

when I watched this my mouth produced more saliva

[@gary_t5862]

same

[@durwin114]

Hehe am the 69th like..NICE!

[@sachinfulsunge9977]

There has to be some neuro science behind this related to yawning and other contagious stuff. JOE NOTICE ME SENPAI

[@besmart]

Spit. Saliva. Drool. Whatever you call it, it's weird stuff. But when you consider all the cool stuff it does, from being the first step of our digestive system to keeping our mouths free from dangerous bacteria, it becomes almost mouth-wateringly interesting.

[@flawq3217]

That's true

[@universeman657]

Okaaaay… XD

[@fatmaninparadise]

Lolz, someone got triggered from the word 'moist'. HA!

[@alexf4500]

Ok fine lets move on(moist)

[@xavierxrc]

No Joe, O'Doyle Rules. (Family drives off a cliff and car explodes)

[@Kram1032]

I really don't get what the problem with "moist" is.

[@xXpallinnXx]

It is a joke about how a lot of people absolutely hate hearing the word moist

[@Kram1032]

Bert The Derp I know. I really don't get those people is what I'm saying.

[@tanktheta]

It's because......they can't get moist anymore. They moisted their last moist. But it was worth it. DAMN SON, THAT WAS A HARSH ONE.

[@Nipponing]

The fuck?

[@sciencepower608]

Mmmmmmmmmmooooooooooooiiiiiiiiiiissssssssssstttttttt

[@perspective1409]

Can I just say that I really appreciate the captions here. So many science channels don't bother with the captions which can leave people out of the learning!

[@swillas]

I don't understand why people hate the word moist, I, in fact, love it!

[@sciencepower608]

Mmmmmmmmmmoooooooooiiiiiiiiiissssssssssttttttttt

[@merevel436]

I do not get it either. It is just word... why is it censored?

[@sulffojus1227]

+John McNemar youll know when your older lol

[@Acehan]

"Moisturize". Pretty nice word.

[@sciencepower608]

+John McNemar just wait

[@selvizhisubramanian]

why did I read the title as spit everything you wanted to know? 😂😂😂

[@illdie314]

I actually love the word moist. It's so unique and satisfying to hear.

[@fleecejohnson2895]

"Coagulated Moisture Dripping From a Dank Tilt." - Most satisfying thing anybody has ever said.

[@keri7031]

Copy cat

[@MegaMGstudios]

*MOIST*

[@someguy2135]

I remember a commercial years ago that got a lot of airplay. Duncan Hines cake mix. They bragged about making cakes that were "moist!" kzbin.info/www/bejne/baDUdplrft2nn7M

[@TheMasonX23]

Finally found some real "spit facts" after Michael teased the concept...

[@ShadowElementGod]

A guy walks into a bar and orders a drink. After a few more he needs to go to the can. He doesn't want anyone to steal his drink so he puts a sign on it saying, "I spat in this beer, do not drink!". After a few minutes he returns and there is another sign next to his beer saying, "So did I!"

[@alphis7431]

tenouttaten

[@AldjinnTV]

Dude keep the good ones for your stand up special on hbo

[@meettalaustinsmiley]

lmao, good one

[@sadickess4108]

+USSR In Soviet Russia…

[@meettalaustinsmiley]

TheGamingKip Kipper In Soviet union, You don't make the jokes, the Jokes make you.

[@fezii9043]

Who else felt like there was more saliva in their mouths while watching this video?

[@stockingsstuffer6302]

So, what's that feeling you get when you eat something that has an overbearing flavor note (eating something really sour, or sweet for the first time in a while) and that area in front of your jaw hinge suddenly hurts really bad?

[@furallds]

Your body will produce a lot of saliva to protect your mouth from the really sweet, sour, salty, etc stuff. You mentioned "for the first time in a while" which means there isn't much saliva in your mouth when you eat those stuff, so your parotid glands will work EXTRA hard to produce a lot of saliva, hence the sudden short pain around your jaw hinge (which is where the parotid glands are)

[@stockingsstuffer6302]

@@furallds Thanks, dude!

[@crispybacon4240]

0:04 Mr. Hanky? DAMN IT, JOE.

[@finisherofwar]

You didn't talk about how licking wounds helps them heal.

[@pokoirlyase5931]

+Samuel Peak yes it does ... It has coagulant (and antiseptic in some people) effect

[@CarootCarrot]

before humans invented soap they peed on the wounds

[@moxiousch]

Interesting! Is that really true? I was under the impression that our mouths carry too many bacteria for that to be effective. For example, if another human bit you, you'd be in pretty bad trouble precisely because of that. Even though spit might have a coagulant effect, wouldn't the bacteria problem override the usefulness?

[@nicolejosan6364]

+moxiousch Your OWN spit is good for you, other's may poison you. HarHarHar...

[@uncharted_soul]

future emperor of the galaxy I could have lived my whole life without knowing that. Thanks!

[@Aeturnalis]

2:55 When I was younger and used to party a lot, I made the mistake of going to bed without brushing my teeth (more specifically, I blacked out in my friend's back yard). The next day, I had the worst breath imaginable, and a cavity. After a few days of pain, I finally went to the dentist to get it filled. I can't say specifically that it was from that one day of not brushing, but that's the only cavity I've ever had, so that's the connection I make. If you only brush your teeth once a day, do it before sleeping!

[@jrrtt25]

the editing, jokes, and audio was great in this video. really important when the topic is so unpalatable to most viewers lol great video as always, and insightful. thanks Joe!

[@mandah0520]

I can't believe no one is talking about the Idiocracy reference. "Glucose, it's what cells crave"🤣🤣🤣

[@Adyot.R]

This channel just keeps getting better and better!

[@sadickess4108]

Can you make a video about corals' territorial wars? The subject really interests me and I'd love it if you made a video about it!

[@yashdeshpande2733]

I thought it was mostly influenced by sea levels and temperatures?

[@sadickess4108]

Yash Deshpande I don't think it was, because in 6th grade, I was in a Marine Science program, and I remember something about corals' territory growing and them having wars.

[@tmhchacham]

Great video, as usual. Keep up the GREAT work!

[@najee_eee]

Then why do we drool in our sleep if we make less spite in our sleep

[@besmart]

Because you're not actively concentrating on keeping your mouth hole closed!

[@Nipponing]

I think you meant spit.

[@najee_eee]

+It's Okay To Be Smart ok thanks

[@Nipponing]

I have a condition I think that makes me over produce saliva when sleeping. =(

[@GamesFromSpace]

Less doesn't mean none.

[@adgames3537]

Since I am out of school you are my teacher :) Thanks so much

[@BarisUnver]

What's with the sound? Did you change editors or something? (The musics and sound effects are too high, compared to older videos.)

[@KnowledgeCrew]

Great video! Apparently what I never wanted to know about saliva was that it is moist... oops, sorry, I said the "m-word".

[@Aarontlondon]

I don't know why, but I've fallen for you Joe

[@josemartoquinojgtc]

In the name of science, I'll watch this video.

[@samwolfenstein5239]

For science!

[@2ndPerk]

So, the correct thing to do with saliva is to spit it out. Collect it in a cup, spend a couple of days gathering it. And when it's filled, you add some ice and have a nice refreshing cold drink.

[@madisonhess7479]

Joe can you make a video about why braces and other orthopedic pieces make you drool more

[@secularmonk5176]

3:02 When my head has been unprotected in cold weather, or when I'm especially dehydrated (generally after going to the gym), if I try to eat too soon after, my parotid glands hurt like a mofo.

[@莓滴滴]

H-Hey you want some spit facts?? - Vsauce 2k16 Actual spit facts - It's okay to be smart 2k16

[@MultiLussebulleN]

I love the aet style of this channel

[@MECKENICALROBOT]

It helps in healing too!!!

[@arifkirmizitas]

Your videos are so amazing. I'd like to watch all your videos and meet you.

[@abdobedo9428]

This is an excellent video

[@BillygotTalent]

Love the sneaky moist at 0:33

[@Msfr1sby]

One of the interesting things is that you will make different saliva if you're choking or have food stuck in your esophagus than if you're just regularly eating. The saliva you pump out in that situation, beyond being copious, has way more mucin than normal in order to get that bolus of food to slide.

[@albertomangia755]

So many sound effects in this video! Made me moist XD

[@luciferbroke7875]

I love this vid so much idk why

[@homeXstone]

0:32 i see what you did there!

[@eliesch]

Me too, it was actually at 0:33-0:34... Lol

[@homeXstone]

yea, but people clicking the time stamp need to be taken to a convenient spot in the video :P

[@dubya13207]

Whenever someone says "moist", I remember "Dead Like Me". Great show, cancelled too soon

[@Elhuggante]

The cephalic phase of digestion begins when we see, smell or think about food and triggers a parasympathetic response that stimulates the secretion of saliva among other elements necessary for priming the gastro-intestinal system for proper deglutition, digestion and absorption.

[@ShahidKhan-eq1gx]

I was just watching your video on the Placebo effect and somehow that video has become my source of reference. I argue with people who support alternative medicine using your video lol. I confirmed each and everything in that video. Thanks

[@shermanstepney2182]

I love the thumbnail without context😂😂

[@flaggkatten]

lol, the sound that the t-rex figure makes at 2:13 is the same noise as the tall deer in Far cry Primal makes when it's angry?

[@musclehank6067]

whenever i wake up my mouth tastes really good and all of the saliva that is produced for a few minutes after i wake tastes really good too.

[@AdmiralBiach]

Cool video

[@tylerkrug8126]

Yes hit us up with the Tommy Boy reference!

[@SamuelBoshier]

At school, we were told in biology that if you keep a piece of bread in your mouth, it will go sweet. It doesn't.

[@hiimjorj6896]

Maybe with honey.

[@SamuelBoshier]

#ffd700Give #ffd700Attention Or Jam (Jelly if you're American)

[@hiimjorj6896]

We have two different names, jam and jelly, they are different, jam being more squishy and has less chunks than jelly, and jelly is slightly harder and has chunks in it, just use Google to see what I mean.

[@dutchik5107]

+Neko Thief we have one name for it, only it sometimes says "with fruit pieces' or "no lumps" but both called jam. yeah, I'm Dutch.

[@hiimjorj6896]

Dutchik Yeah, for me the label usually says fruit preserves on it.

[@tuanhnguyen7734]

Nice hair style!

[@tinahan1244]

"thats where most of the cool spit happens" i see what you did there

[@anilchadha2429]

Nice shirt .

[@tuanhnguyen7734]

Like your hair! 😊

[@Altorin]

hahaha.. that tommy boy reference was perfect absolutely perfect

[@WHiT3_SHAD0W]

Shoutout to Mr.Hanky at the beginning 🤘

[@Squigdude13]

Saliva is so important, yet we need it so much. It's like an old shoe, you think it's gross, but you will never get rid of it.

[@Bersekro]

Excelent video. Im teacher in Brazil and I learn very much with you. Thanks for share

[@gojimoji9085]

I pray for your students spelling capabilities.

[@Daft4LifeRevolution]

Don't make fun of foreign people who make grammatical or spelling mistakes when writing in English. It means they know more than one language, which is impressive when compared to the average American.

[@gojimoji9085]

Safari Ari There are two kinds of people in this world, those who understand sarcasm, and you.

[@Daft4LifeRevolution]

You do realize that when you type something as opposed to speaking, it is hard to detect sarcasm. And this definitely applies to someone who clearly isn't fluent in English. Think about it.

[@NoName-bf4gk]

+Safari Ari

[@paullobontiu6715]

gimme some of them spit facts boi

[@largestmeat]

Vsauce should have made a spit facts video

[@annyjadi3054]

xXx came here looking for this comment

[@RafaelRipollGallardo]

One of the funiest videos of this channel. LOL

[@tanktheta]

I am making a hell of a lot of Moist jokes. Because I was moist before this video.

[@huntersihelp]

To bad they're all terrible and hold no humor in them at all...

[@tanktheta]

Net_Chix_AnKill? Cool, or it's just your interpretation given that alot of others have enjoyed my moistness on this video's comment section.

[@estebanlaguna4580]

i just love how he slips in moist xD

[@haai45]

Maltose, it gets converted to maltose. Later in the duodenum, it's broken down by maltase, an enzyme which is secreted by the pancreas.

[@mohamadzalzala7805]

Wait! So you said that less saliva is produced when a person sleeps, right? Does that mean that after brushing your teeth and not going to bed immediately after brushing the bacteria will start to destroy your teeth even though you brushed them, right? Which probably the reason as to why my teeth are decaying even after I started to brush them before (I take HOURS to fall asleep) sleep.

[@SlyPearTree]

Drool rules? That's the furthest thing from my mind when I wake up in the middle of the night with my face resting in my spit. Thanks for the video

[@nabusvco]

Hey, Vsauce, Michael here with some spit facts

[@ArtezzGaming]

How can anyone think this is disgusting? this is most fascinating.

[@charlywow4460]

Anyone else watching this while eating?

[@musclehank6067]

me i was eating a brownie :)

[@FSM_Reviews]

I'm eating cereal.

[@amberjade0123]

I can’t believe I’m eating while watching this

[@s1gm42]

That spit looks rather suggestive!

[@nmheath03]

Not to mention it lowers chance of infection if put over cuts.

[@maxhill9254]

thx

[@thatdude2k9]

have some of my starch breaking liquid girlfriend XD

[@tanktheta]

HENTAI!!!!!! Hahahaha

[@dogeasaurusrex7421]

You have a liquid girlfriend? That's pretty weird

[@tanktheta]

Dogeasaurus Rex It's called a slime girl.

[@Nipponing]

You have a starch breaking liquid girlfriend!? The fuck?

[@dogeasaurusrex7421]

Samuel Peak Without commas, you can interpret it however you wish,

[@kitr.1930]

... looks like I have to start brushing my teeth before bed.

[@philanderson7992]

spit facts

[@JacobCorumWilliams]

Eating cereal and suddenly becoming aware of my saliva is not a nice feeling

[@cloudricklloyd1]

I actually love the idea of saliva in the right context

[@faithallen7993]

I’m sure he said “ok then, let’s move on moist” at 0:33

[@saudiprince6532]

You've almost got a million

[@veganchaatparty]

Super Superb!! Super Superb!! Super Superb!! Thanks.

[@cassidyleonards2411]

Why do I drool onto my pillow then?

[@icedragonaftermath]

You know, when I was growing up my mom always told me and my little that she loved us more than spit when I was growing up. Usually in out little group we'd have a couple grumblings about that being gross or about that not being a lot. At that she'd almost always follow it up with something like "Really" and "I think you'd be pretty sad if you didn't have any" a what not. As goofy as it may have been, I don't really think we got really appreciated it until we move from Seattle to Phoenix (long story) and actually had a chance to get a little parched and cotton-mouthed every once in a while. I know it's probably not all that relevant to this particular video, but my point is to not take stuff for granted even if it's not the stuff about you or the people around you that you like thinking about as being or necessary. That's just not how things work, you included. That said, I should actually get around to watching the video at this point. PS: If you for this far, thanks for listening or in this case reading. I really appreciate it and hope you have a good day.

[@nicolejosan6364]

Could you make a video about Xylitol? My friend is a dentist and said that those sugar eating bacteria go *POP* when they eat Xylitol. No more free Acid.

[@natelewis4470]

I've been avoiding this episode for so long but I've watched every other episode and I really wanted to watch a new one. god damn first world problems

[@austinmhepner]

0:30, let's move on moist

[@70jcarbon]

I learned this last year

[@bencesarosi7718]

Love the reference to Idiocracy

[@GregoryRichardstheman]

If I produce less when I sleep how am I still producing enough to wake up to a *moist* pillow sometimes? Or are my cheeks actually that flat against my pillow?

[@mowu8459]

i want to see more youtubers doing the saltine challenge

[@Lucifer-li3nj]

speaking of mouth watering i was eating a sandwich made with rye, ham, american cheese, and pepper jack

[@gnomee9447]

So many word puns. I'm drowning!

[@kevinmillard1323]

**gritty, deep voice** _moist_

[@connorconnor2421]

3:22 did you get that from My Talking Tom??

[@jackkruse9088]

These little jokes that have recently been put into the videos. 8/8 m8

[@fartzinwind]

Chew, Chew, Chew, good food is good for you. Chew, chew, chew: that is the thing to do

[@leFoodeater]

I couldn't stop thinking of the saliva in my mouth...

[@VoidHalo]

The trick to the saltine challenge is to crumble them up before you put them in your mouth.

[@espoppelaars]

Mouth water is an even grosser word than moist.

[@demfeels7349]

Can your next video be about animals' sleep?

[@matthewfennell7886]

Just before the intro plays as he says "let's move on" listen carefully... Did you hear it? The sound... Of me wasting your time

[@tanktheta]

Did you hear it? The sound... Of me being moist

[@zeromailss]

close but no cigar

[@flubs2298]

But he actually did say moist...

[@tanktheta]

Pie Empire Yes I did.

[@tanktheta]

Samuel Peak I will

[@stormday1063]

I see why when I place some over spit in my mouth on to my shirt and then accidentally re-wrap my tung around the same spot where I previously placed my tung at it tastes like awesome-nees lewl! ^-^