How much sleep do you really need? | Sleeping with Science, a TED series

You know you need to get enough sleep, but the question remains: How much is enough? Sleep scientist Matt Walker tells us the recommended amount for adults and explains why it's necessary for your long-term health.
Sleeping with Science, a TED series, uncovers the facts and secrets behind our nightly slumber. Check out more episodes on TED.com: go.ted.com/sle...

[@Jerome...]

Damn ... under 7h and over 9h are the only 2 kinds of sleep I get.

[@beowolf4572]

bruh, you gotta listen to what he actually says, it might not be the quantity itself of sleeping 9+ hours but other hidden factors to why you'd be needing to sleep longer than 9 hours....

[@Jerome...]

@@beowolf4572 If it wasn't clear, I sleep over 9 hours during weekend because I sleep like 5-6 hours during the weeks, like many others. People call it catch up sleep. There, I explained it for you.

[@beowolf4572]

@@Jerome... Did you even read what I said? He was saying sleeping longer than 9 hours itself wasn't the cause for increased mortality, and that there were other hidden causes for increased mortality for anyone sleeping over 9 hours, and not the long sleep itself. So you should be okay with your weekend sleep of 9 plus hours, assuming it's just catch up sleep and no other hidden health factors. And you just mentioned one possible cause for your increased mortality risk, lack of sleep during the week. And yes I get it, not everyone can sleep the ideal 7-9 hours, especially if you have kids or a newborn.

[@bernhardtrian7471]

@@Jerome... i dont know so much about the topic but it could be also the relive of stress. Stopping to going to work at the end of the weekend makes you sleep more instead off just getting the right amount of hours.

[@gaurav3794]

Rip in advanced

[@mangogo21]

Me: watching this video instead of sleeping

[@igdagastdwipayana1564]

lol me

[@artema.]

same

[@blueberriechiiizcake]

I knew someone will comment this for sure.

[@debbiecholt]

Me too 😵

[@rachelvoss5519]

LOL Me, too!

[@MechMiko]

Science: You need 7-8 hours of sleep- Mind valley: THATS A LIE

[@MechMiko]

Sorry, I despise that ad

[@dwarfyman4899]

It’s awful

[@anantsharma7955]

Mindvalley is awful.

[@sahilsaksena3199]

Ikr it's so fucking annoying. "Stop ! Don't exercise. Please don't" 💀

[@fazzadon8944]

@@AnkitSingh-ku5je KZbin channel

[@Fassnight]

TED - "You need good quality sleep." Also TED - "You better get the perfect amount of sleep or you will die"

[@xufeisun1397]

They do justify each other don’t they?

[@whatisahandle221]

Unspoken: “BTW, when we say ‘You,’ we mean They statistical average of all You out there, not really any particular person.”

[@Kaledrone]

You will die regardless

[@MarTimator]

Schools: Three, take it or get out

[@julz6077]

wtf what type of school you got to?

[@julz6077]

@@Farmlover453 sounds like you do something wrong when you only get 3 hours of sleep either learn too much or too much free time

[@Asinine_37]

Ya it could be really devastated for u not only in ur life but also to ur academic.

[@miminghadoop]

@@julz6077 tru

[@aggammer3485]

I like how nobody got the reference

[@user-ib4bg9kg5s]

I started sleeping before 11pm everyday, it changed my life. I'm in a better mood always and I'm more productive, sleep is essential, no wonder it takes up to 8 hours of our day

[@ninjapirate123]

I only sleep late when I have homework, maybe I should quickly finish my homework and then sleep early

[@njbrx]

@@ninjapirate123 yeah do that, I start uni again in march of next year and I want to have a consistent sleep schedule by then

[@fardinshuvo]

@@njbrx i,m also aiming to get used to a good routine..now i sleep at like 12 pm and wake up at 7 pm..this is messed up.. I trying hard to change my sleep cycle

[@malikushamayb6389]

And me watching this at 3 a.m.

[@niccolom]

Not a problem if you wake up at 11am.

[@gamil867]

A little bit sooner than you (2:23 am)

[@jaydeepparmar3879]

@@gamil867 bit earlier 😂😂😂1.32

[@abhikshitdas]

@@jaydeepparmar3879 bit more earlier 12:52 am

[@yoshimitsu001]

@@abhikshitdas still earlier : 22:31

[@mahshshsrklingfa7031]

I alternate between 11 hours of sleep and 5 hours of sleep from night to night. I am gonna die guys. Good bye

[@adityabagdi1178]

F

[@0xsunil]

RIP

[@lunareclipse2571]

F

[@deefee701]

Remember it's an average of 7-9 hours. That's the sum total over several nights. So don't worry. Google how averages work.

[@apoorvk8634]

F

[@Zecce93]

You should read this guy's book: Why we sleep. Good one.

[@DegreesOfThree]

I thought his book was called The Art of the deal?

[@user-eh5wo8re3d]

it seems to be riddled with errors, miss representation of data and claims not supported by data at all

[@strength4147]

@@user-eh5wo8re3d For example? He always gave references to the studies he had mentioned as well as the data.

[@shad2617]

@@strength4147 He makes pretty bold and baseless claims. Such as "the WHO has declared a sleep loss epidemic", 2/3 of adults don't get the recommended amount of sleep or how lack of sleep will outright kill you or double your chances of getting cancer. None of these claims are based on research or any facts, just massive overstatements. The book is just full of fear mongering, bad and inaccurate scientific knowledge. But hey! Bill Gates recommends it, dude's a billionaire. He must have everything figured out.

[@shad2617]

Everyone who read or was thinking to read "Why we sleep" should have a look at this: guzey.com/books/why-we-sleep/

[@fkmyoutube]

Is it just me, or am I distracted by his hair.

[@adityabagdi1178]

Now I am distracted too ☹️

[@hadeela.8315]

Lol😭😭

[@YuleNevano]

trumpesque

[@antiv]

It’s not only you. I find his hair disturbing.

[@danibot3000]

Same here, might be unfocusdness which comes from poor sleep quality.

[@dailydoseofmedicinee]

Sleep helps control our metabolism and weight, promotes stable moods, helps prevent cardiovascular diseases, boosts our immune system/function, increases knowledge retention, and helps us with long and short-term memory. Sleep is also essential for brain functioning.

[@alexrosario8562]

Wish my bro saw this comment and took it serious 😭

[@yigityigitoglu7451]

Gamers: *Chuckles* I'm in danger.

[@Bankai90]

Underrated statement. As someone who still loves gaming as a grown up. I probably haven't slept well for the last 20 years LOL. Idk if I had more all nighters or more full restful nights in my life xdd (iksde's in fear)

[@fkmyoutube]

TED: The importance of sleep Also TED: Releases 3 videos simultaneously

[@Slam_24]

'The shorter your sleep, the shorter your life.' Now that's a paradox if I've ever heard one.

[@alonzenajee]

And if the spirit is truly immortal, then not sleeping woud mean that you will live forever, right into the next life.

[@Slam_24]

@@alonzenajee Interesting way to view it. Personally, I don't believe in the spirit of the human body, but our image or memory of who we are might as well live on forever if we work at it.

[@AbelPerez-hg5du]

It’s scary 😟

[@spookypeet4763]

Conclusion: I will die anyway

[@gargee29]

🤣😂😅

[@nadirbashir5082]

🤣🤣🤣🤣🤣

[@naveensenapati9032]

He looks Donald Trump on a keto diet

[@kesia21]

Ikr😂

[@avibrarbrar]

Lol

[@vale.a.m.6419]

HAHAHAHAAH

[@MudahnyaFizik]

😂😂😂

[@dimazsaloka9053]

exactly

[@inuka6969]

*Fun fact : If you don't sleep, you feel sleepy*

[@badhil4468]

Fun Fact: If you feel sleepy, you go to sleep.

[@jewel9218]

Fun fact: People die when they are killed

[@badhil4468]

Fun fact: Fun fact isn't fun anymore

[@GammaFZ]

fun fact: being a criminal is illegal in denmark

[@ssrini2002]

@@GammaFZ damn! Why do people still stay there? 🤔

[@kimdavis2433]

I'm aware that children and teenagers need more sleep than adults - when does that increased requirement begin to drop off? I ask because I'm 20 and still sleeping around 9 or 10 hours a night lol

[@acidset]

Yeah 20+ is already on that 8 or 7-8 hours. I used to oversleep when I was depressed and taking medicine, it is just as devastating as under sleeping, so you definitely want to see if there's any underlying cause. I'd start by cutting down screen time some hours before bed and going to sleep and waking up at the same time. Go cold turkey for a day, I know that's always worked for me. Be active or you will not be tired at the end of the day.

[@huaiscrblol5077]

I think the answer can vary for everyone -- granted, I'm no expert on sleep and this is just my opinion -- but there are many factors to consider, such as if you're still growing. 20 is still close to the teens, and there's no reason to cut your sleep short if it doesn't negatively impact you. If you have time to get tons of sleep, and if 9-10 hours is the perfect amount of sleep you need to function, then there isn't much reason to force yourself to wake up earlier. However, be careful of oversleeping too.

[@Plan-ETs]

Lol I’m 15 and I get 6-7 hours

[@huaiscrblol5077]

I'm 16 and I get around 8. I'm just saying, there's no cutoff line or any specific schedule you have to follow for your age, just sleep enough, what works for you. Everyone requires a different amount, what Matt Walker is talking about in the video just says the recommended amount.

[@acidset]

Going cold turkey and walking 2 hours in the morning fixed my sleep instantly. Something I had been struggling for more than a decade, gone. Now that I couldn't walk for a few days, my sleep is all over the place again. So don't make it hard for no reason, the truth is that for most of us all we need is to replace a few bad habits. Wake up and go to sleep at the same times, be active during the day (even just walking 8000+ steps), use flux and Twilight and cut down screen time hours before going to bed. Cool down and relax before going to bed (read a bit and journal), have a cool room. I use Vapidbobcat's 8D playlist most of the times, or some other rainy café ambience videos. If there's not much noise around me, then nothing at all.

[@fikaimu]

The higher mortality rate in people who sleep too long is correlated, but not causal. It's just that seriously ill people who are hospitalized are inevitably going to sleep longer.

[@ramonbs6075]

The first sentence is correct, but not the second one. The correlation on something that everybody does, for that long, is not as negligible as you might present. Sleep deprivation is a real deal. You can death if you don’t sleep for (I think I got it right) 11 days.

[@shaheedmohammed280]

Epidemiological studies has many ways to overcome the bias you mentioned. They may be tracking apparently normal healthy individuals rather than those having serious diseases.

[@FPA33]

thats an interesting fact!

[@fikaimu]

@@ramonbs6075 What I mentioned here is about people who sleep too long. I don't understand why you are talking about sleep deprivation.

[@ProtoMarcus]

I am pretty confident that specific group in the second half of your comment has *_negligible_* impact on the statistics and data *EDIT* - That is accurate - hospitalized individuals were not part of the data _(across at least 16 studies)_ - so they do not impact the data

[@Olibelus]

This is the reason we have sleep anxiety nowadays. Because everyone’s throwing numbers and words like “decreased mortality” etc. at us, making us more anxious about sleeping enough.

[@Oblivion1407]

Kynario true, a single night of bad sleep doesn’t kill you

[@erikaamot72]

I sleep very soundly, go right to sleep and when I wake, get right up feeling fine .. 6 hours typical .. my whole adult life 67 years old with same BMI as at 20 .. 19.1 .. no aches and pains .. still flexible .. no known health issues

[@bwilks3056]

Thank you for sharing this. I, too, sleep for a short amount of time, but when I’m up, I can do cartwheels. Tons of energy. Hoping to have a low BMI like that at your age. Congrats!

[@makodefensegroup4767]

Lemme just tell the military i need 7-8 hours of sleep because a ted video told me to

[@cornsbread]

Or just go to bed earlier.

[@nikos7250]

@@cornsbread 🤦🤦🤦

[@straightdoinit]

Oh wow thanks for your service you hard working man

[@Natalia-cm8ez]

Salute to you man

[@utkarshagrawal3640]

My brother is a sleep master, he can sleep whenever he wants to!

[@Neys_Nest]

hahaha

[@nadirbashir5082]

Hey , mine too

[@harukeyn5580]

What's your opinion about sleeping twice a day? For example I sleep 5.½-6 hours in the night and always take a 30-40 min nap at noon. Personally I feel like I have more energy for the entire day than when I sleep for 7-9 hours

[@lazerzz2514]

As far as i know that's not very helathy as your short nap doesn't provide the rest that deep rem sleep does

[@ProtoMarcus]

There is increased evidence and data that suggests and supports the idea that *_many_* people are biphasic like most humans used to be! Biphasic sleep was the "norm" for most of humanity, especially before electricity and artificial lighting

[@5MinutePsychology]

From my professional experience I can say it’s not only about the amount of sleep but rather about the quality of sleep

[@saswotlamichhane5862]

*Man, I am feeling Sleepy!!!*

[@ninjapirate123]

yawn

[@00Resev]

I'm finding age to be a factor as well. I am now 41, and i'm sleeping a lot less hours than i did only 10 years ago. On week days, i tend to sleep on average 5 hours, and waking up naturally, and refreshed. On the weekend, when/if i have days off work, i seem to go for a bit longer, up to 8 hours. Perhaps its merely my internal clock working on a steady rhythm, but age does seems to be a factor.

[@ifeelembarrassedaboutthisa9792]

Me: *needs 7-9 hours of sleep* School at 6am: WAKE UP WE'RE GOING WOOHOO

[@davisnicholas9123]

Sleep early

[@ninjapirate123]

And whats worst is when u have homework

[@Shazistic]

You can’t pour from an empty cup. Take care of yourself first. -The Shades 🖤🤍🖤

[@QuestionEverythingButWHY]

“The best bridge between despair and hope is a good night’s sleep.” ― Matthew Walker, Why We Sleep

[@FallenAngelHiroko]

Everyone is different. There's no one size fits all. I let my body decide. Because no matter how hard I try, it'll sleep when it wants to. The only exception of this is depression because it's not sleep, but an escape from your internal and external problems. Something I learned the hard way. I think the big problem we have is that we FORCE ourselves to sleep which gives us poorer quality.

[@benaziirfatima6998]

😢😢

[@arnabpaul4117]

Just weak up. Now motivated enough to sleep again. Thank u.

[@user-wy1py1zs1o]

TED: you should sleep 7-9 hours ME:sleep all the day *_*

[@2.5dworkshop36]

Ted: "the longer you sleep the faster you die" Me who sleep more than 10 hours a day: 😐

[@redache467]

He didn’t say that, he explained that therr are confounders affecting the results, so he really give us no conclusion....

[@micodeleon8164]

I can't take him seriously with this beiber hair lol

[@Natalia-cm8ez]

Hahahah ikr

[@Justinjoise]

Dont judge a book by its cover

[@akidnamedkush]

Dont cover a book by its judge

[@ssrini2002]

Please continue the Think Like A Coder series, I absolutely LOVED it

[@Junkyu-hm5dk]

Before watch this:sleeping is the simplest thing out of my life After watched this:sleeping became as difficult as my homework

[@rajarampatel601]

Yea dude, i also noticed that, before i was ok and i was not sleep deprived also, but when i started to watching videos after sleep, buah now i feel m constant need of sleep. KZbin has ruined my life

[@lochiewildey3851]

Watching this at 3am

[@vidhac5430]

1:22 for the little piece of fact

[@xlben10]

Love this series! Keep up the good work

[@sowmyapasumarthi1430]

I didnt want to come here but quarantine has bought me

[@justinekim4102]

Whoever animated these series, let me buy you a coffee. This is so brilliant and creative - I love it 💕

[@user-kh4wn5lt2j]

Buy me a coffee

[@csmlegend3704]

This is the type of video that my school watches when deciding how much homework to give me

[@MGTOWPsyche]

I have found that sleeping 2-4 hrs at a time is enough to get a 15 minutes of deep healing REM sleep 2 times a day. I usually sleep 5-7hrs a night and take a 1-3 hr nap in afternoon if I have the time!

[@Larry21924]

This piece is a landmark; much like a book that was a landmark in its exploration of similar themes. "Better Sleep Better Life" by Author Name

[@homosapien5156]

Some top level professional athletes sleep for 10-12 hours. Does that help in recovery ?

[@marcosmimenza]

The hours you need to sleep depend on who you want to sleep with.

[@IamRanJos]

Perfect

[@vaishnavrajput8669]

Amen

[@yunusaydin5177]

Thank you for good working Nihal and Miraç ❤

[@connerpowersyoutube]

Thanks Mr. Walker

[@Asinine_37]

Matt walker!!! Really appreciable thank u

[@JESUS-666]

I love me sleeping,it gets me closer to death.the feeling of feeling nothing is awesome

[@logannelson6473]

Why is Dr Matt Walker actually Best Jeanist from My Hero IRL

[@sokkongharry]

Watching this at 3 am. Nice

[@nicknameprivato]

I'm watching It at half past five am

[@dannyth5413]

I am a person that wake up at about 6 in the morning and gets ready for bed at 9-10 of the night. I get mocked at by some for keeping this up during summer, with some cheat days. Others congratulate me and ask me how I do that. I personally find much comfort in my sleeping schedule and would recommend it to most people that have the ability to be at bed at thay time.

[@colltonrighem]

Three videos about sleep at once?? Please don’t do this to me I don’t wanna think about sleep I just woke up :(

[@RNorthex]

Or the mortality rate's increase might also be because a large number of people who spend more time sleeping/resting often tend to also have less physical activity in their schedule.

[@lukes2219]

This is by far the best ted talk they’ve had in a while

[@lukes2219]

Or red talk series

[@SybalJanssen]

Ran across a work on butenkyo breathing where a comment was made that only four hours of truly deep sleep was required. The extra hours were the result of restlessness caused by poor breathing. Speaking only for myself there feels like there is validity. When my mouth is taped closed I sleep very deeply

[@watermylon6495]

do you have a link to the source? im intrigued

[@dontjelletme6855]

Me: watching ths video waiting for my netflix dowload and getting ready starting to watch another 2hrs of netflix to start my tuesday with 4 hrs of sleep

[@healing-waves]

"Calm mind brings inner strength and self-confidence, so that's very important for good health." -- Dalai Lama Infinite Love Beautiful Soul! ✨❤

[@Skulltroxx]

he definitely doesn't look like someone who's sleep deprived... ok, I'll listen to him

[@zubby3846]

Ahhh yes

[@omowako]

Me at 2 AM: I need to sleep--wait ted ed posted I can spare 2 minutes

[@dolphinexpert2748]

Great series. Always wanted to learn about sleep more.

[@itouchtheskyslowlifeitaly]

I sleep 5 hours a day here on the top of the mountain. Thank you so much for talking about this topic.

[@Mittyboyds]

Thanks for your clear explanation

[@cirusMEDIA]

This did not answer the question in the title ... it just asked more questions.

[@linyuan123]

7-9 hours, no?

[@flavioptferreira]

@@linyuan123 Not necessarily: Up until recently studies have implied that sleeping more than 9 hours may reduce longevity in humans. But these studies seem to have left out elements that show correlation, not causality. Science is now starting to lean towards the conclusion that the more you sleep the longer you live, regardless.

[@strength4147]

@@flavioptferreira For me personally, my sleep time is always different and i don't know why. Sometimes my body wakes up after 8 or 9 hours of sleep and sometimes after 6 hours of sleep.

[@acidset]

@@strength4147 cause sleeping has its cycles, you want to wake up at the end of a cycle or another, but never during one. Anyway, there's so many factors to that, usually it's disturbance from either outside or something you drank/ate or have done during the day that will affect your sleep.

[@acidset]

Are you an adult? 7-8 hours. Sleeping more now and then is fine but regularity is key anyway, and you don't want to waste daytime either.

[@TerriblePerfection]

I don't care how much other people sleep. Why would I? It's not a competition. I sleep when I'm tired and get up when I'm rested. It's not really confusing or controversial.

[@olegtvorecz6591]

Mortality likelihood is 100% so mortality risk doesn’t concern me at all

[@adamsc1181]

Im so grateful i know this. Thank u

[@taraquinch1256]

As a child an teenager I slept 7-9 hrs. As a working adult I can't stay asleep longer than 5- 6 hours..

[@kinjjalkhare3367]

2:07 okay so that's me😶. I wonder why can't I sleep when I am sleeping 🙄

[@shankarrai5467]

Me watching this at 1 am

[@vijiyanttanaji9800]

6-7 is the ideal sleep for me at night , if I snooze for more than 10mins I wake up lazy. Afternoon nap for more than 30mins is waste of time.

[@MrBebopChamploo]

Is there any research on the impact of *when* you get your 7-8 hours of sleep? Like, is there a health impact from sleeping from 4 am - 12 pm vs 10 pm - 6 am? I feel the most well rested if I go to sleep around 11:30 pm and wake up around 8:30 pm. However, my regular sleep schedule recently has been more like 4/5 am - 2/3 pm...

[@ElatedElate]

the only thing i know is that the peak performance of someone who wakes up earlier is always higher than the peak performance of someone who wakes up later, even if both people get enough sleep

[@GareebNavas]

@@ElatedElate I think that would depend on the individual. Although to be able to wake up early has an advantage because the schedule of jobs, school etc favours early risers.

[@awesomedavid2012]

It depends on your chronotype

[@carloorelli3538]

6 hours are fine for me. Also: the reson for the longer you sleep the less you live is because, ofc, the more you lie in bed the less you move, exercise and use your heart properly. 10 hours in bed it's no different than staying 10 hours on the couch watching Netflix.

[@brandin14]

Tip: blink longer

[@topgurl9313]

Great video, thank you.

[@JimWilbourne]

This might sound stupid, but I've always had a hard time finding an answer to the opposite of this: "How long should you stay awake?" I've always wondered this because knowing this could help me fine-tune my sleep schedule. I don't have a traditional job, so I have the ability to do that, and I'd love some research on this. I want to know how long I should stay awake before I recharge so that I make the best out of my hours awake.

[@chadanderson9872]

The correct answer is… it varies. Your body needs rest and recovery more than specifically sleep. A Hindu monk who meditates all day exerting little energy may only need 3 or 4 hours of sleep a night. An athlete or body builder is going to need that 8-9 hours of sleep.

[@Eric-gk2yw]

Great. I'm just shy of 40. I can only sleep about 5 hours a night. Bed at 1:30am. Rise at 6am. Bed at 9:30pm. Rise at 2:30am.

[@allezvenga7617]

Thanks for your sharing 👍

[@bentrider]

Correlation does not equal causation. There are so many factors that determine how long each person lives. To just pick one, like hours of sleep per night, is absolutely ridiculous!

[@morphyne187]

I couldn’t sleep more than 6 hours if my life depended on it, but apparently it does.

[@WatchingPup]

I think one should find out how much they need by experimenting. I found out that if I sleep less than 7, it's not enough, not fully rested. I need 8 if I'm really tired. But more than 8 makes me feel groggy or I get like a headache. And when I'm sick I sleep from 8 to 12 hrs.

[@h3w45]

For me when I sleep 8 to 11h I only get 1:30 deep sleep but when I sleep 5h almost half of it is deep sleep.

[@anandreuz]

Please answer this question. Before 1980-1990, there were barely any television in rural India, most people used to go to bed by 8 pm and wake up early by 4 or 5 am. But they used to sleep in daytime as well for 1 or 2 hours. Now time has changed. My grandparents are old, above 80, and my mother is 50 years old. My question is does sleeping in daytime has any effect on mortality.? I don't think I will be able to convince my grandparents to change their routine that they have been following for their entire life but I will try to convince my mother given any research has been done in this field.

[@user-zd1pg5pw1j]

I d like that you include teenagers and kids ,because they are different

[@sharinaross1865]

I typically get 6 to 7 hours of sleep. Naps are for babies and old people. One time I went on a sleep date.

[@invox9490]

I think they should see WHEN thye get sleep. You might sleep longer or shorter, but if you do that in the daytime, the result can be very bad for your health. That's why people who work shifts should have some form of "regulation" to regulate their sleep habits, thus making them healthier workers.

[@saaketh83]

Im a simple man, I see a new Matthew Walker vid, I click

[@jaimanohar]

Need to sleep but watching this.

[@heidinolen873]

As long as I get 2 hours, I'm good. More than 6 and I'm funky all day. ...is that your real hair? The presidential?

[@cliffmode2000]

Thank you for this. 😂

[@pomidorboic6964]

So this is the first time im being told straightforward that ill die sooner with both of ver. 1 and ver. 2 explanations. And im kinda shocked, even crying. God i just wish to be normal and i hate my disease so much

[@chrislow1236]

holy crap. I sleep 6 hours on weekdays and 11 hours on weekends. I am dead.

[@calvinoleary]

I was literally like damn I sleep so much I’m safe. Then right after he says “the more you sleep your mortality risk actually goes up.” God damnit…

[@andi-ox5jb]

I am not kidding,you definitely remind me of Richie Rich

[@graysonpipher3991]

Why did he go wild at the end with the productivity comment?

[@Sancsentity]

Cool hair, and thanks for these 3 helpful episodes!

[@AdamEspinosa]

It seems that he's just highlighting the problems with observational studies. This is why we do experimental studies. It's definitely hard though with long time spans and large samples.

[@thresagraham8181]

Are we just ignoring that this gentleman looks like he has a giant shredded wheat on his head? 😮🌸🌺✌️