More Consensus on Coffee’s Benefits Than You Might Think | Hacker News Reader

More Consensus on Coffee’s Benefits Than You Might Think

nytimes.com

81 pointsmgav80 comments

Without the information who financed these numerous research results, they are not worth the time to read them or to write about them, imho.

You have to view it at an individual study/paper level (ie: go to the link and pdf via the article). They have to declare sources of funding in the papers, so you can trace funding origins and conflicts of interests from those declarations in each study.

The article itself does a nice job of linking to every necessary study - sometimes they don't bother and then you do start to get worried about how much of the content is accurate.

http://en.wikipedia.org/wiki/Ad_hominem

No, that would be calling out the author by name as a shill. Remarking that the source the author is relying upon could possibly be biased/tainted is not an ad hominem in any way.

It could be considered an ad hominem attack on a study if OP had said "the source was funded by coffee sellers and therefore it's all false and incorrect". But that's not what's happening here anyway.

The OP is "implying" that based on who funded the research, this may be truthful. So while the claim was not made outright, it was insinuated.

If the strength of an argument depends partly on trusting the integrity of a source, why is doubting that integrity a fallacy?

In an ideal world you judge experimental results by their reproducibility, but who on HN has the time to reproduce results?

If all you are doing is casting reasonable doubt, that's fine. The logical fallacy arises when you point to the source of a proposition and declare that mouth that spoke it makes it false by nature. There's a big difference between "This pro-coffee study was funded by Big Coffee, so I'm skeptical and would like further studies and independent verification" and "This pro-coffee study was funded by Big Coffee, therefore the conclusion is false and coffee actually isn't good for you." Even if Big Coffee funded this report and benefited from its conclusions, the conclusions may very well still be valid; it would be a fallacy to reject this possibility outright.

Careful, OP isn't claiming that a lack of funding data makes the article false or inaccurate. The point is simply that (in OP's opinion) some of the most critical information needed to determine whether or not this article's conclusions should be taken seriously is missing. This is not an instance of an ad hominem fallacy.

I agree it wasn't a perfect fit - I'm not fluent enough in debate terminology to know, maybe this? http://en.wikipedia.org/wiki/Association_fallacy

I don't think there was a fallacy involved at all here. If in fact critical data is missing, then OP is right to point that out. This doesn't inherently negate the conclusions of the article (and claiming that it does would in fact be a fallacy), but I don't think OP was claiming that anyway.

The article also relies heavily on a metaanalysis, not just individual studies. Meta analyses are designed to take a large multitude of studies in the same area and ascertain an effect size. By examining everything in aggregate, this should counteract any funding bias -- or reveal it if the results get skewed (i.e. lots of positive results and lots of negative results but no middling results). Additionally, meta analyses usually consist of a "file drawer" search where they get their hands on a bunch of the unpublished papers and analyze those as well to ensure they counteract any publishing bias for printing papers that only show positive results.

I don't know where you got the idea that metanalysis is mostly unpublished work. I've never seen a published meta analysis like that. Most journals wouldn't print it.

It's happened in some notable cases; for example, a major review of reboxetine, a Pfizer antidepressant, obtained unpublished data from German health regulators and demonstrated that there was no benefit over placebo. The published data gave the opposite impression.

Eyding, D., Lelgemann, M., Grouven, U., Härter, M., Kromp, M., Kaiser, T., et al. (2010). Reboxetine for acute treatment of major depression: systematic review and meta-analysis of published and unpublished placebo and selective serotonin reuptake inhibitor controlled trials. BMJ, 341. doi:10.1136/bmj.c4737

But yes, it's not standard practice. Meta-analyses try to check for publication bias but they do not systematically hunt down unpublished results.

I work first hand in a research community and I've never seen a meta analysis published that was based solely on unpublished works. However, most of the good ones consist of a mix of published and unpublished works to ascertain whether there's a real effect or whether there's been a publishing bias that doesn't reflect the total body of research. A good meta analysis will take the time to discuss their methods for selecting published works and any efforts they made to solicit unpublished works such as contacting prominent authors in the field, getting on mailing lists, etc. The good ones also tend to discuss how they analyzed the papers for selection, discuss the paper stats (i.e. we started with 200 published papers and 20 unpublished ones, after winnowing this got reduced to 130 published and 10 unpublished), and how they collapsed results to calculate effect sizes etc.

Meta analyses should include as much of the published literature as possible for the research question they're attempting to answer AND they should seek out unpublished works. The meta analysis will consist primarily of published works, the unpublished works are collected to counter the presence of positive result publishing bias. This provides a fuller picture of the research field than simply relying on published works. After they've collected the articles, the researchers analyze the collected works to ascertain which ones actually address the research question(s) they're attempting to answer, they toss everything else.

Coffee itself might not have anything to do with it; rather, coffee follows a certain lifestyle which is healthier than that of non-drinkers. I.e. it is perhaps quite good for you to get up every morning at 9am and go to work. Active lifestyle, continuous stimuli etc. Coffee just so happens to be very ingrained in that culture.

It might not be the actual chemicals and nutrients of coffee that helps you, but the fact that it "forces" you to be active, mentally. It kickstarts your brain. The biggest killers are staying still and loneliness.

That's my thought too. Is it the coffee itself or is it the lifestyle that goes along with drinking five cups of coffee a day? I'm pretty sure that no one is drinking five or six cups of coffee a day and just sitting on the couch and watching TV.

I'd argue that coffee is connected to a rather unhealthy lifestyle of sitting in an office chair the whole day, eating unhealthy fast-/restaurant food instead of cooking for yourself, working long hours instead of a regular 7 to 5 schedule etc.

I'd argue that you're both middle-browing the f* out of an article that actually quotes several actual scientific studies.

I love the term middle-browing. Both comments weren't about the immediate effects of coffee, though, but about their indirect benefits. At least I didn't want to say anything about the immediate facts at all. The position of the article and its beautiful quotes is kept virginly untouched.

Coffee is ingrained into the culture of many professions, far beyond just office jobs.

Nursing, landscaping, utility work, construction, you name it...it's a great way to kickstart the body when having to get up at 5am or, stay awake during an overnight shift serving tables at a restaurant.

> Coffee is ingrained into the culture of many professions, far beyond just office jobs.

Exactly, so it could be very silly to claim that any benefits to coffee are actually because of it being a part of healthy lifestyles.

I too, like the GP, don't exactly equate coffee to healthy lifestyles, because of my interactions with various people where coffee is used to extend the day far past where it is healthy to do so.

> it's a great way to kickstart the body when having to get up at 5am or, stay awake during an overnight shift serving tables at a restaurant.

These are not healthy activities, but I still think that coffee being a part of so many both healthy and unhealthy lifestyles makes trying to equate health benefits of coffee to being just a because it's part of some healthy lifestyles silly.

There is a lot of writing about how coffee fueled the industrial revolution which happened way before people sat in office chairs all day.

> http://www.npr.org/programs/wesat/features/2001/coffee/01090...

> I'd argue that coffee is connected to a rather unhealthy [...] working long hours instead of a regular 7 to 5 schedule etc.

Since when did 7-5 (which is 10 hours) become regular?

Quite some research in rodents supports the statement. That would suggest that coffee works without the typical lifestyle choices, at least unless coffee-high rats are programming till the sun comes up.

(A Scientific American article about a similar research from last year: http://www.scientificamerican.com/article/coffee-and-tea-may...)

My two cents is in keeping my daily coffee - and leave the causation vs. correlation debate for later.

Anecdotally, I would agree with you for some, but for others not so much. I get a short boost followed by a long crash when drinking coffee. It's also like an unfocused focus - like as long as what I want to focus on is nearby, I will do that. But if I have to figure out what I want to focus on, that feels like frustration and hypertension.

I prefer tea. I get up at 4:50 am 5 days a week, and I rarely sleep past 7-8 on weekends. I just make sure I'm asleep by 10:00 pm before work nights, and weeknights I stay up til 11:00 max.

I really like thinking that I think slowly, and that I can control my thinking direction using another level of meta-thinking. It's one of my most favorite and dramatic life shifts as an adult, that I have made. Pretending that my mind is a machine that needs to be turned on is a one way ticket to crazy town, and it's pretty hard to leave crazy town.

But otherwise, I don't understand how loneliness has to do with any of this. I'm lonely regardless of whether I drink tea or coffee.

Agreed, coffee for me is basically a burst of energy/focus followed by a longer period of worse energy/focus than when I began, so really not worth it for me. I like Yerba Mate for this reason - no real crash, but a strong but steady warm buzz, much less peaky than coffee.

Coffee also creates an energy sine wave for me, the amplitude of which is too intense. I go for matcha green tea powder in my morning shake - the effects last longer since your body is digesting a powder (it's extended-release caffeine), with little drop-off. I tolerate it much better than coffee.

Wow guys, I also have rather bad times on coffee! Its really hard for me to find any information on the subject as well.

Sometimes I have really bad times of it, particularly on low sleep(ironic?). It can cause me to become a bit more anxious, have trouble conversing with people as if I'm hungover, and cause context swiching issues.

The OP was saying that being lonely is worse for your health than drinking coffee.

I am very curious. How would a typical day look like when you wake up at 4:50? Do you need to commute very early, or do you use that time for yourself? I personally wake up, get ready and leave, while I do all my things late evening / during the night.

I leave my house around 5:10, I get to work at 6:50ish. I leave work from 3-5, and depending on traffic, I get home anywhere from 4:30 to 6:30. Then I shower, blow dry my hair (~45-60 min), then I eat (~30-60 min), then I code/study, then social email / doctor who, then sleep.

I don't have a ton of free time, but I make it work.

Tea contains l-theanine, which, when combined with caffeine, has been shown to improve concentration. You can get the same effect by drinking coffee and taking l-theanine pills.

The amount of l-theanine in green tea is quite small compared to what you get from pills. From my own personal experience and from what I've read on nootropic discussion boards, to really feel significant effects you need more l-theanine than what is provided in tea.

"Coffee itself might not have anything to do with it; rather, coffee follows a certain lifestyle which is healthier than that of non-drinkers."

I think it's much simpler than even that.

Health fads and science results come and go, but over thousands of years humans develop (just a few) heuristics based on subtle observations along the way. One of the best of those heuristics is "an apple a day keeps the doctor away".

Bear with me here...

Is it flavonoids ? Special anti-oxidants ? Some weird apple chemical that we can isolate and realize all of our dashed resveratrol hopes with ? No. An apple a day keeps the doctor away because it keeps your bowels moving, all else being equal. That's it. Just a big, boring macro effect on your body and your bodies primary consumption/waste pathway.

I suspect the same is true with coffee. Special secret antioxidants ? Natures hidden chemical compounds we can distill into a pill ? No ... coffee is just a good laxative[1] and if you're having 2-3 cups of coffee a day you're (all else being equal) moving waste along (relatively) more efficiently.

Which is great. Nothing to be sneezed at - just like the apples - but also nothing exotic or confounding.

[1] http://www.onemedical.com/blog/live-well/why-coffee-makes-me...

I also wonder if it's something intrinsic to coffee, or just a result of the caffeine. Stimulants like caffeine can improve blood flow and potentially stave off arterial plaque build-up.

You are assuming the scientists who did these studies and the scientists attempting to merge them with meta-analysis are asleep at the wheel and have failed to correct for obvious confounding factors that a random member of the public could brainstorm in the seconds it took you to post.

This doesn't seem like a sensible assumption, absent evidence.

Hey Julian,

I really wasn't trying to discredit any of the studies done. Whenever I participate in discussion my main motivation is always to try and create nuances. I know before hand that an actual truth is impossible to attain, so I feel it's better to just try and add some color to the discussion.

Causation and correlation is of course always low-hanging fruit, I just felt it was curious that the article did not touch upon it and wanted to fuel a different angle of discussion.

As a general rule, devils-advocacy (being the process of advocating a position you don't agree with because you think it isn't getting enough air time) is unhelpful verging on concern trolling.

If it's a strong argument, why hasn't it convinced you?

When you do that, you emit weak arguments that are easy to knock down but send the discussion off on a tangent.

I never considered nuancing a discussion could be unhelpful, but I think I understand your point. There's some kind of underlying truth we're attempting to uncover, and in your opinion, I'm derailing by "nuancing" through devils advocacy; submitting arguments I do not actually believe to be worthwhile.

I'm wondering though, does it have to be so black and white? Can't I believe partially that what i'm positing is worthwhile, or at least have a feeling there's something to uncover down that avenue, without being entirely convinced? I would assume bouncing half-baked ideas off each other could be valuable (though I do recall a bunch of studies debunking Brainstorming, which I guess this is similar to).

>The biggest killers are staying still and loneliness.

My alone time, recreation time, time dedicated to meditation are some of the best/heathiest times for me. Being amped up all the time is messed up, imo, and leads to chronic stress and such.

>coffee follows a certain lifestyle which is healthier than that of non-drinkers. I

The fattest slobs drink coffee just like everyone else. It seems you've never watched the clientele in your average breakfast or donut place.

I find people addicted to caffeine and stimulants seem very busy, but often deliver sub-par work as soaking your neurons in excitors feels good to you, but actually doesn't make you better at anything. If anything, it makes you worse than you normally would be.

I think there's a great argument here about how slow and steady wins the race and is healthier overall. Look at US over-working conditions, lack of maternity leave, lack of vacation days, etc compared to our more genteel European peers. I can't imagine anyone thinking our amped up culture is better from a health perspective.

>Coffee itself might not have anything to do with it; rather, coffee follows a certain lifestyle which is healthier than that of non-drinkers.

Which is what most competent research controls for in the first place.

Besides, coffee is something so prevalent that even junkies and never exercizing couch potatos do it, so it kind of controls itself.

Anyone else surprised that 3 to 5 cups a day is considered "moderate"? I thought it would be 1 to 3 or so.

In the US, at least, there's a strange convention that a "cup" of coffee is 6 ounces[1]. 2 mugs is typically about 4 of these "cups". I'm not sure what convention the NY Times is using, but the quantities are quite muddled.

1. http://cooking.stackexchange.com/questions/25041/is-a-cup-on...

I always hated that "cup" measure in the US... Anywho, I don't think the volume of coffee one drinks in a day is relevant without stating how concentrated it is. I'm assuming 6 oz of americano coffee doesn't have quite the same effect as a 6 oz cup of esspresso (oh Lord.)

I know that, technically, a glass of beer should contain the same amount of alcohol as a shot of vodka or a glass of wine in a bar. Of course in practice it's probably not exactly the case, but when someone tells me "drinking 2 glasses before driving isn't such a good idea," I'm supposed to be able to tell how much 2 glasses is regadless of the alcohol consumed.

Isn't it the same in the article ? Shouldn't a cup of esspresso contain the same amount of coffee as a (medium ?) americano ? If not, how do these 2 coffee dilutions compare ?

Google says 6 oz. of coffee has 71mg of caffeine. https://www.google.com/search?q=caffeine+in+a+cup+of+coffee

Starbucks 'tall' has 260mg of caffeine. http://www.cspinet.org/new/cafchart.htm

This article is completely worthless because it is all about looking at studies about drinking coffee. If you really want to get educated about health, you need to learn the details of taking care of your entire person, how all your body parts are interdependent and affect each other, and what different habits actually do. Instead of looking at whether or not long term it lowers or raises your risk of certain problems, it would be better task these questions: What is coffee? What are the immediate affects of drinking it on different body organs and functions? What is the purpose of those organs and is that purpose disrupted? How does it affect digestion? It is well known among those that actually know stuff about health, that taking care of your digestive process and things that affect your bowel movements is where the root of most disease and healing begins. So how does coffee affect this? According to the book "Tissue Cleansing Through Bowel Management", coffee will kill the good bacteria necessary for this faster than anything else. If that is true, it makes a strong case toward coffee being bad for you. Of course not all coffee is created equal. Some coffee is naturally less acidic than others. A lot of coffee is polluted with high levels of heavy metals. But if coffee is generally bad for digestion, and digestion is one of the main keys to healthy living, why do so many studies show long term benefits from drinking it? Here is where I don't like studies for this kind of thing. Most people come nowhere near living in harmony with what is now known about healthy living, myself included. So these studies are mostly about the affects of coffee on people who otherwise do not live a healthy lifestyle. Also, who funded, setup, monitored, and published the results? Who gamed the system by deciding who be included in the study and what type of coffee they would use? Who was paid off to change the numbers? There is no way to know. And yes, I drink coffee, at least for now. But I am on a constant journey of always improving my health in some way. Some day, I may stop drinking coffee altogether.

For some people with GERD, coffee is very bad for them. My wife switched from coffee to tea for this reason. Tea is pretty fabulous for her, and I gather there's at least some documented health benefits on that front as well.

Edit: GERD = http://en.wikipedia.org/wiki/Gastroesophageal_reflux_disease

Second Edit: To be clear: I agree with the parent article, I think coffee is close to harmless for MOST people, and very well might have some positives.

Tea is awesome. It has the caffeine, but has another drug which is more calming. For people who get a bit manic with coffee, tea is often the thing that works for them.

L-Theanine one of those other drugs found in green/black/white tea, and it produces a calming effect. The Japanese even put it in bubble gum.

This is very true. I have LPR (not GERD, but often mistaken for it) and reducing coffee consumption to reduce stomach acid production is the driver here. Tea can, I'm sure have benefits... but what kind of tea? You can make "Tea" out of anything. Coffee is very specific, Tea is way to general. You would have to study so many specific types of tea to see where and how much benefits exists.

GERD?

commonly known as acid reflux

A thought.

Coffee is a (relatively mild) stimulant. I wonder how much of coffee's benefits can be attributed directly to that, as opposed to whatever else caffeine may do?

Given that these studies tend to be done in first-world countries, where obesity and people being underactive are a problem... Overgeneralizing of course.

If nothing else, sitting still for long periods of time is known to be bad for you, and caffeine helps people avoid that.

This article brought to you by Starbucks. The great tasting and dependable coffee you love.

It's fun to watch the health pendulum swing to and fro, and occasionally given a gentle shove from a marketing article.

Replace coffee with cigarettes, and it reads as a tobacco ad from the 1920s.

This is all well and good. I drink my locally roasted, manual ground, aeropress brewed coffee for pleasure and taste. Everything else.. meh.. Actually most/all coffee lovers I know drink coffee because they like it, not because they expect a lot of health benefits from it. But... good to know..

I use it as a caffeine delivery system primarily.

Tablet form is probably more effective :`)

Remember when moderate consumption of alcohol also reduced cardiovascular risk?

Yes. Doesn't it still?

No, it was debunked.

I remember that doubts were raised about some of the studies, but not that it was definitively debunked. Do you have a reference by any chance? I'm not doubting you and realize that I can Google, but if you have a good paper I'll start there.

According to Wikipedia references it doesn't seem to be debunked at all.

http://en.wikipedia.org/wiki/Alcohol_and_cardiovascular_dise...

It's a drug. It's full of harmful chemicals because of the way it's processed. It affects mind and body, often negatively. But it's great money maker so we will be hearing more about its "benefits" in a near future.

Also tobacco and alcohol are big moneymakers, but there is a large consensus about their negative effects, and that's why their use (or abuse) is discouraged, by doctors and governments alike.

So either:

- The coffee "lobby" is more effective than the tobacco and alcohol lobbies.

- Maybe all drugs cannot be dumped in the same bin, and we should treat them case by case, critically.

The consensus wasn't always focussed on tobaccos/alcohols disadvantages though. If you watch movies about the US's 60s you'll see doctors advising their patients to smoke more.

Hmmm... seems like I see a new story about the purported health benefits of red wine every few months or so.

Fun fact smokers process/eliminate caffeine from their bodies quicker than non-smokers.

This is true. Blood serum caffeine is processed twice as quickly by smokers.

LPT: If you quit smoking, cut your caffeine consumption in at least half for at least the first week. Otherwise you will explode with non-nicotine-related episodes of anxiety or nervousness.

you're treating "chemical" as a four letter word

To quote RZA watching Bill Murray drink straight from the pot- "Coffee causes serious delirium."

What harmful chemicals are those, exactly?

Surprisingly few. I would have expected anything arriving in US stores at an industrial level would have suffered from industrial levels of processing and storage-related chemicals, but a quick skim of wikipedia reveals essentially none. Huh.

https://en.wikipedia.org/wiki/Coffee_production

Ethyl acetate is sometimes used in decaffeination.

https://en.wikipedia.org/wiki/Decaffeination#Solvents_used_i...

Trichloroethylene, acrylamide, and many more including pesticides like Aldrin, Dieldrin, Chlordane and Heptachlor.

> It's full of harmful chemicals because of the way it's processed.

Like which chemicals?

Dihydrogen monoxide, for one. :-)

That looked serious, but the smile at the end of your comment made me curious enough to look it up and learn it's H2O. Nice one - you got me!

Do you have any evidence for your claims?

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