Sleep duration, chronotype, health and lifestyle factors affect cognition [pdf]

Those who abstain entirely are disproportionately likely to be former alcoholics - which explains eg the apparent protective effect of moderate drinking

This is a situation of correlation ≠ causation, because — as all Rick & Morty fans know — some geniuses are drinking copiously just to slow down their turbo-charged intellects. :-)

Hypothesis: The better you understand the world, the more likely you are to need an occasional drink.

Every study I have ever read emphasized importance of sleep. Many show grey matter reduction long term the less you sleep. Sleep studies literally use a little alcohol to disrupt sleep. All the research out there indicates alcohol also directly shrinks your grey matter. These findings are hard to believe for sure.

The study appears to say alcohol consumption has protective effect on cognition. Those who drank had less cognitive decline compared to those who abstained completely. If this is correct, this directly contradicts the other studies that says alcohol has zero benefits?

So the Ballmer Peak is real!

https://xkcd.com/323/

Some might just be avoiding falling asleep or being even less capable.

In the EU it's quite normal for the average person to get the 8 hours of sleep. Of course, it depends on the work sector you are in, but for most jobs you don't have to wake up at 6 AM. Also, most people live close to their work, within 30 minutes of biking/driving/public transport.

I work a full time tech job, I am out with friends or on a “date night” with my partner three or four times a week every week, and I have a few hobbies like music production and combat robotics.

I get at least 8 hours every night. My “must be home and in bed” time on a weeknight is by 12:30AM, and I sleep in until 8:45AM. I am normally woken by my alarm.

Weekends I simply set an alarm for 9 hours after I get in bed, which sometimes means sleeping until 2PM.

I don’t eat breakfast, and I basically never commute in the morning, but if I do, my office is about 15 minutes away.

I go to sleep at 9:30 and wake up at 5:30 every day. Sometimes I go crazy and stay up till 10, but that's rare. My bus leaves at 7 AM (40 minute commute), so that's plenty of time for coffee & breakfast & a shower before I have to head out the door. I get home from work at about 4:30 PM, plenty of time to cook dinner or do home stuff or go see friends or whatever before going to bed at 9.

idk it's normal for me but then again i live in Denmark and i dont have any children

I do sleep 8+ hours each night (Netherlands): Up at 7.30, leave at 8.15, 30m commute. Leave work at 5.15, get to sleep around 10.45.

Interestingly everybody replying to this is saying they spend ~8 hours in bed, which most certainly means they aren't getting 8 hours of sleep :)

Most days I'm in bed (and asleep withing 5 minutes) at 22:00 and awake at 05:30. I'm over 60, 7.5 hours sleep is just right for me. I have a one-hour commute each way and usually leave home at 06:45 and arrive back around 18:00.

It doesn't matter what time I go to bed, my eyes pop open at 05:30 and I have to get up (a) to micturate (did I mention I'm over 60?) and (2) feed the cats. The latter have trained me using medieval methods. When I was younger I would sleep as late as I could: my record was sleeping in until 16:00, and boys oh boys did that cause me to feel wretched.

"Normal" in the context of the body's actual sleep needs, not "normal" in the sense that everyone has the time or life management skills to achieve those needs.

("Normal" also depends on age: babies sleep a lot more than 8 hours a day, teenagers also typically need more sleep than they actually get.)

I ran a consulting business for a long time. Sleeping that much is no problem if you prioritize it. Kids, wife, etc. You just have to organize your life around your priorities. It does mean little time for extraneous entertainment during the week, but that’s ok.

My breakfast is a cup of coffee and toast usually but since I live a 25 min bike ride from my work (in New England USA) I can usually leave around 800, which means I can sleep at 2300 for 8 hours easily.

Now, does my body do that?... no, usually it wakes me up after 6-7, but whatever.

Long sleep duration often presents with poor sleep quality, which negatively impacts cognition.

"Long total sleep time may suggest prior sleep deprivation, medical conditions, or effects of medications."[1]

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4246141/

I’m about to hit 40, and I’ve had this exact same experience. Even a single beer, shot of whiskey or glass of wine will leave me feeling depressed for at least a day afterwards.

For me it seems to correlate with having had COVID back in 2021, where prior to that I could still have 2-3 drinks and feel okay the next day. My suspicion/intuition is that it has something to do with a shift in my gut microbiome - from what I understand, alcohol can very easily disrupt one’s microbiome, and the state of my microbiome seems to have a significant influence on my mood.

I haven’t missed the alcohol though. It’s actually been a blessing for my general health and wellbeing.

How much of that is your ability to metabolize dropped, versus the strength of common drinks has sky rocketed? Especially mentioning IPAs. It is not uncommon to find them in the 9% range. I remember drinking a ton of Guinness back in the day. Highly amused to find that that would be considered a light beer today.

There is some new evidence that changes occur at various stages in our lives, specifically one in the early-to-mid forties, that can affect things like alcohol metabolism[0][1]. I find this type of thing and the "epigenetic clock" research to be pretty fascinating to read about now that I'm approaching mid-life myself.

[0] https://www.scientificamerican.com/article/drastic-molecular...

[1] https://www.nature.com/articles/s43587-024-00692-2

I had a similar thing until I stopped eating a certain brand of muesli. A different brand with seemingly the same ingredients was fine. I think it's something to do with processing of dried fruit. I believe there was some reaction between that and the alcohol I consumed later in the day. I only realised it was breakfast related on holiday and my breakfast habits changed. I found drinking to be consequence free as opposed to 1/2 a pint causing a certain headache the next afternoon. I experimented when I got home and completely solved my problem.

I was also in my early 40s when this happened for what that's worth.

Same here. Quit alcohol when I turned 40, the side-effects the next day of even 1-2 beers were not making it worth the buzz during drinking. Sleep issues, less focus and concentration, weaker performance in the gym, anxiety the next day etc. etc. It became a no brainer to simply stop drinking. To those with better ability to metabolize alcohol, cheers to you.

My experience is similar. I can tolerate at most one cocktail, glass of wine, or beer (although I'll go malty over hoppy every time). One positive is that because of this limitation, I think I enjoy the drinks I do have a lot more.

A change that came along with this is some kind of sensitivity to sugar. I love candy and baked goods. A short stack of pancakes with maple syrup and berries is the best, but that kind of carb bomb can leave me feeling almost hungover.

For me, the type of drink makes a huge difference the older I get.

I used to like wine, but the older I got, the more I started noticing having a terrible hangover the next day, even if it wasn't enough to get actually drunk or even buzzed. Type/brand of wine didn't seem to matter. But whiskey or vodka mixed with soda, no problem.

Post-30 I found any amount of alcohol I really noticed the next day and concluded it just wasn't worth it anymore.

I'm a similar age and also a heavy drinker (15-25 drinks per week) but also run 40-50 miles per week + 5000-7000 feet of vert per week. My friends/family are astonished that I can crush 10 beers in an evening and run 15 miles the next morning w/o food. I suspect metabolism has alot to do with it.

So, I could get behind a lot of the idea you are pushing here. But, I question whether you have evidence to back it up?

For one, to claim that most developed countries have purged ritual feels more like you are referring to some specific rituals. Or have amusing cuts on what you consider developed countries.

You also sort of undercut yourself by noting that alcohol hits people in different, if repeatable ways; but you seem to think that will not be true for other drugs? From my experience, I would expect the same for pot. Tobacco, I confess I never really saw it impact anyone. Outside of getting them addicted.

Simply stated, why do you think you would not see such variability of how other items impact people?

Alcohol is...the safest [psychoactive drug]

Yeah, no. According to CDC data, more than 150,000 people die from excessive alcohol consumption per year [1], which is about how many people died of heroin overdoses in the past 20 years [2].

By and large, the labels "safe" or "dangerous" are subjective and highly cultural, at least when it comes to substances.

[1] https://www.cdc.gov/alcohol/facts-stats/index.html

[2] https://www.cdc.gov/overdose-prevention/about/heroin.html

Alcohol is one of the most STANDARDIZED substances on the planet. 5% at 500 mil is always going to be the same amount of alcohol. Of course it's going to be predictable and socially acceptable. Try doing any other drug and you have no clue what you're getting, even if you get it from the the same source time and time again.

The predictability is a FEATURE. And btw, it's not boring at all.

You are conflating boring with predictable.

Safe compared to meth maybe but not compared to caffeine.

Setting aside alcohol addiction, the costs of alcohol abuse to your health (e.g., brain damage, liver disease, etc.), and the risk of killing yourself by drinking too much in a sitting, there's also the way it drastically increases the risk of drunk driving and domestic violence.

I'm not saying we should ban it or anything, but we should not be underplaying the very real risks and costs associated with it.

"all with their different nuances in how they alter mood and thinking patterns"

This is honestly not true unless you are including absinthe. Ethanol is the only active ingredient and it has one of the most well understood dose-response curves and one of the most heavily studied effects. The rest is all in your head.

There just isn't that much to the alcohol, it's very one note, moreso than any psychedelic, moreso than even smoking (where dose control significantly varies the effects) or even cannabis which is also relatively one note.

In the US it’s far more acceptable. I don’t drink and while I’ve been offered, no one ever pushes back. And I’ve never had problems being the only one at parties who didn’t.

You mean why abstinence isn't causing better cognitive performance, right, RIGHT?

Obviously the study result is BS. Because if the the same people, drinkers with higher than their abstinent peers cognitive scores, didn't drink, their performance would be THE SAME.

But it's impossible to find out. They should totally continue to study all that, tho. Maybe at some point in the future we can cut people open alive and look properly inside, fuck around & find out, and then close them up and send them back to work again.

Nah. As a night owl myself it’s simply that I have trouble falling asleep due to an overactive mind. Add two hours or more of rolling around and instead of getting up at 7 I’m getting up at 9.

And before someone chimes in with sleep advice, please don’t. I’ve tried it all. Some rings help a bit but at the end of the day nothing makes enough of a difference. I just need those two hours my feet to the point when I can sleep.

Also no, going to bed before everyone else is not an option. I’m not giving up having a social life.

Even when controlling for what’s noted, I’ve always been more productive of an evening and have been since a child. It’s not limited to me and there seems to be some genetic component. My mother, grandmother, aunts etc. All night owls, and all of us averaging 6-7 hours of sleep at best.

Regardless of what’s occurred before hand, my brain seems to kick into some higher gear at around 9-10pm. Like there is a noticeable change in my energy/cognitive capabilities.

Ironically, the only time this has ever deviated was two months I spent in Russia where for the first time in my life, I adapted almost instantly to what one might call a “normal” sleep schedule. As soon as I returned to my own time zone, it reverted back to me being a night owl again.

I’ve given up attempting to work around it and simply moved to a role that can accomodate it. It’s been huge for my physical and mental health to end the 30 odd years I’ve spent fighting what seems to be a natural schedule for me.

I personally find daylight itself to be "distracting" -- like that basic sensory input alone consumes some non-trivial amount of cognitive energy. I much prefer to think in a dark space. I've never met anyone IRL who relates to this though.

Owls could have the same amount of productive focus time in the early morning before everyone else starts to distract them - the reason they chose not to do that is mostly due to chronobiology, which is determined by genes, not social constructs like "lunch time".

I found that a basement is a good substitute during the day. Reduced noise, distraction and no sunlight which often changes intensity every time a cloud rolls by.

That’s me! But instead of going to bed late, I also try to get up very early to have the silent environment you describe.

So seeing the other comments disagreeing maybe what you’re describing is a different kind of night owl…

Disagree. I'm a night owl, and I work best with bustle around. Silence is eerie and distracting. I would keep the tv on when studying late into the night and I worked best in groups.

I would argue no because, while you’re doing stuff that matters to you, everyone else is done with their day and partying. You’d just be asleep while everyone else is pretending to do their work.

Aren’t we all just offset normies?

Before we rush to conclusions and make up just-so stories, note this passage from the research:

"The relationship between cognitive function and lifestyle factors such as alcohol consumption and smoking proved complex. Individuals who abstained from alcohol showed lower cognitive scores than those who consumed alcohol, conflicting with previous research[1] that has connected moderate drinking with cognitive impairment"

[0] https://en.wikipedia.org/wiki/Just-so_story

[1] Topiwala A, Allan CL, Valkanova V, et al. Moderate alcohol consumption as risk factor for adverse brain outcomes and cognitive decline: longitudinal cohort study. BMJ 2017;357:j2353.

A hunch would be that alcohol abstinence is strongly correlated with religious fundamentalism which is correlated with lower income and cognition.

It seems you are pointing to second largest religion in the world - islam. It covers over 2 billions of people. They largely don't drink not because they are fundamentalists, they just follow basic premises of their religion. And my various travels to various countries with them being either majority or minority its extremely common, even when they resettle ie to Europe. There are also completely dry countries in North africa for example, they are not full of religious fundamentalists.

Please educate yourself about the world a bit before making such harsh and discriminating statements, they have no place on this forum.

its an interesting idea, but its very complex because of varying attitudes to alcohol within and between religions.

It is interesting that fundamentalists tend to be anti-alcohol across religions with different attitudes in mainstream believers (say Christianity that commonly uses alcohol in religious rites and hose founder's first miracle was to give people alcohol, Buddhism, and Islam which is clearly anti-alcohol).

I think that means you are onto something in that there is an important correlation there. Not sure it is as simple as lower income (there are lots of rich fundamentalists of all religions) or cognition. Personality traits or associated cultural factors more likely?

Furthermore, drinking weekly seems better than monthly.

Would seem to potentially imply more routine social activity / community.

"BMI seems to have almost zero effect."

Seeing how chubby Jon von Neumann was, this should be trivial. ;)

I knew that smoking crack meant I was smart

This is funny. I started mixing ~3g of creatine into my morning coffee a couple of weeks ago. I never thought of it being stimulating or activating, but it's certainly possible: I usually don't stick long enough to things like this to form a habit, but my brain seems to nudge me into keeping up with it...

I dont really have ADHD, but one time on nat geo channel i saw this video where they test two people , they were supposed to not sleep. after 12 hours they both were given coffee, one was allowed to sleep 30 mins, other was not . the one who had a nap recovered really well but the others conditioned worsened and he went to sleep even tho he didnt wanted to, his body gave up.

I do, nicotine works this way for me.

Have you had a sleep study done? You may have low oxygen saturation when you sleep. I had literally no symptoms of sleep apnea, no major risk factors, but my body was struggling to breathe when I slept due to my anatomy. I have started CPAP treatment and am excited to see if my cognition improves despite not really feeling bad.

Deviated septum as well, but it's not the only reason for drying mucous membranes, which I never got around to getting checked. In part, it results from nutritional habits, sometimes (still), a bit too much coffee but the amount that causes it varies so it must be something else in one of the underlying metabolisms.

A few weeks ago, I tried Nasal Strips again, and for some reason, they are helping now and the difference is like day and night. I can only assume that it's because I got older and my life style changed, including nutrition, which was really bad when I was young. So dry mucous had too much effect for me to notice the benefits of the nasal strips or it's really just the bigger size of my nose :P

But the biggest change, compared to my young years, is that I am much more resilient to unhealthy stress and not continuously stressed as I was back then, when I was also regularly exposed to stress amplifications without time to recover.

And being able to breathe properly through my nose now amplifies everything for the much much better: mood, psychological resilience, performance --both cognitive and athletic-- time to fall asleep, sleep, with the latter two coming with their own boosts for the next day.

Most notable was the effect on my facial muscles. With the loss of those specific tensions came a direct effect on focus and concentration and self-control, which is all, to a great extent, mediated by the prefrontal cortex.

I sleep with Breathe Right strips. It's changed my life. Whoop band and 8Sleep confirm.

Just read Breath by James Nestor. You can thank me later. Fellow ran experiments on himself (and monkeys too) on exactly that, mousebreathing vs. nosebreathing. The difference is drastic. Catasthropically drastic.

To the contrary. It's possible that the correlation is caused solely by a culture that raises owls as larks, "dumbing down" the latter with individuals maladapted to the lark life style. The effect could be increased by smarter owls being able to resist the conversion therapy a little better than less smarter owls – resulting in a selection bias.