Comment by StanislavPetrov | Hacker News Reader

Comment by StanislavPetrov | Hacker News Reader

StanislavPetrov

What the author didn't mention, and I haven't seen mentioned in these comments, are the extremely beneficial health effects of coffee (not caffeine, decaf has shown the same benefits). Most significantly, studies have shown that coffee reduces overall mortality rates significantly, with the reduced chance of dying from any cause increasing with coffee consumption (up to a point).

>Compared with nonconsumers, participants in the highest quartile of coffee consumption had statistically significantly lower all-cause mortality (men: HR, 0.88 [95% CI, 0.82 to 0.95]; P for trend < 0.001; women: HR, 0.93 [CI, 0.87 to 0.98]; P for trend = 0.009). Inverse associations were also observed for digestive disease mortality for men (HR, 0.41 [CI, 0.32 to 0.54]; P for trend < 0.001) and women (HR, 0.60 [CI, 0.46 to 0.78]; P for trend < 0.001). Among women, there was a statistically significant inverse association of coffee drinking with circulatory disease mortality (HR, 0.78 [CI, 0.68 to 0.90]; P for trend < 0.001) and cerebrovascular disease mortality (HR, 0.70 [CI, 0.55 to 0.90]; P for trend = 0.002) and a positive association with ovarian cancer mortality (HR, 1.31 [CI, 1.07 to 1.61]; P for trend = 0.015). In the EPIC Biomarkers subcohort, higher coffee consumption was associated with lower serum alkaline phosphatase; alanine aminotransferase; aspartate aminotransferase; γ-glutamyltransferase; and, in women, C-reactive protein, lipoprotein(a), and glycated hemoglobin levels.

http://annals.org/aim/article/2643435/coffee-drinking-mortal...

In addition, according to other studies, coffee prevents and/or reverses liver damage due to alcohol consumption. One study suggested an extremely significant (44%) reduction in occurrences of cirrhosis among those who drink 2 cups of coffee a day.

http://www.reuters.com/article/us-health-coffee-liver-cirrho...

When considering whether or not to give up your morning coffee, consider the good with the bad.

I have read these studies and often wonder if it is not the coffee itself, but rather what you aren't doing when you are drinking coffee.

For example, coffee suppresses the appetite so maybe you snack less and that is driving the difference in the two study groups. Or people on the non-coffee drinking group have Coke-Cola instead.

I feel very badly for my Grandparents, who were told not to drink coffee because it was "bad" for them. They all stopped drinking coffee in the early 90s and subsequently put on a ton of weight and then suffered all the related health problems (diabetes, heart failure).

I often wonder if they stuck with coffee instead of giving it up would they have been in better health.

I'm the original author. I did mention that there may be health benefits to caffeine. You make a good point that it may be coffee and not caffeine that people find beneficial. Nevertheless, as I mentioned in the post, I'm skeptical of reports of the benefits of consuming something as most such reports come from entities trying to sell you something or people who want to rationalize their own consumption. I'll try to update the post later to clarify.

> I'm skeptical of reports of the benefits of consuming something as most such reports

You should be skeptical. But skepticism shouldn't drive you to claim something like "most reports".

I'm not sure what you mean. I never said "most reports" other than saying "most such reports" have implicit bias. Would you dispute that? Most articles I come across about the health benefits of coffee/caffeine seem to just be reporting the same popular science tropes without any scholarly backing.

I wonder if some of this is due to a subtle intervening variable like conscious or subconscious (i.e. fidgeting) decisions to exercise more accumulated over time because of increased energy, rather than caffeine per se.

If that were true, decaf wouldn't show the same effect because it wouldn't give you increased energy. (I don't drink decaf)

Well decaf does contain caffeine, just less of it.

Typically less than a twentieth of it with most modern caffeine methods.

In epidemiological studies we refer to these variables as confoundimg variables. There's another term as well that I can't seem to remember.

When you try and correlate one specific variable, like coffee, to trends like mortality, you must control for every other variable. Socioeconomic factors like income generally cause confounding of your results.

For example, there was a recent paper that showed that women with gum disease were at higher risk for certain cancers. Is it a wide stretch to believe that people with gum disease may be of lower socioeconomic status, and also probably not take care of their diets and health anyways?

Can someone link the PDF? My login for the acp journal article the parent linked to describing the health correlations won't work for some reason. I want to see how they controlled for some of these factors.

Edit: I found the full PDF through my institution. They note that their study may contain confounds, and note possible ones that they tried to control for. The paper isn't perfect, but I applaud the authors for being as thorough as they could. That being said, this sort of article is bound to go viral as soon as possible, with many misleading headlines.

> epidemiological studies

Tough field... How do you survive with the overwhelming stigma of doubt connected to it?

I'm not involved in any epidemiological studies, simply a medical student :).

But that being said, I think a lot of the stigma comes from researchers using biased data, or acting unethically with their data. Good epidemiological studies exist that have improved the health of the general public.

As a guide for new readers of public health research, here are my suggestions:

1. Read the abstract. Think about the claims that are being made. For example, if someone tells me that drinking 2 cups of coffee a day leads to a lower risk of cancer, my first thought is: what kinds of things do people drinking 2 cups of coffee a day do that would lower their risk of cancer? Could they have a different diet? Do they make more money, leading to them being able to afford preventative health? Do coffee drinkers just have more awareness about their health? Do their regular schedules and sleep cycles give them a health advantage? Keep these questions in mind when reading the rest of the paper. See if the researchers tried to control for these easy alternative explanations.

2. Get a fundamental understanding of some of the statistical terms and calculations used, and make sure you are not misinterpreting them. Thinks like odds ratio, attributable risk, relative risk, etc. Each of them means something specific, and should not be used for extrapolation. Google is your friend!

3. Read the paper as completely as you can!

4. Especially look at the discussion section for maybe reasons that their data isn't great, or also discussing alternative explanations. Also look at their appendix for their exclusion criteria. This can be a clue towards whether or not a researcher is being genuine about their dataset or data collection. In the ACP article about coffee drinkers, there were quite a few exclusions made, and the population they pulled data from seemed biased (women who went to mammogram screenings might care a bit more about their health than the average person)

That's all I have for now. I'd welcome any actual researcher to provide feedback and suggestions!

For a more complete list of all the health benefits of coffee, and separately of caffeine:

http://nutritionstrategy.com/coffee-good-or-bad/

Coffee is full of antioxidants

That is one of my pet peeves. There is no proof that antioxidants are good for humans. Years ago I read an article by a researcher that traced the origin of the idea to... nowhere. There was never any research that indicated they are good for us. It's one of those things that was injected into a news cycle and was picked up and repeated over and over again.

I can't speak to antioxidants specifically, but this is a pet peeve of mine as well.

My girlfriend can attest to my going on tirades when a miscellaneous holistic "health expert" shows up on morning talk shows to inform daytime tv viewers that if they put an onion under their bed and only eat foods that don't contain the colour white that they'll reduce the "toxins" in their house and their body. (fictional example) Those mysterious boogeyman toxins... gotta reduce those toxins. Oh and you're selling a supplement that will take care of all of that for me so that I don't have to walk my pocketful of okra around the block three times before soaking it in a bath of cold milk I must change every day if I want to stay healthy.

I'll stop now, but I could go on...

Not so fast, if you're under 55 years old and drink more than 4 cups a day then this study found that it is pretty bad for you.

>A study of more than 40,000 individuals found a statistically significant 21% increased mortality in those drinking more than 28 cups of coffee a week and death from all causes, with a greater than 50% increased mortality risk in both men and women younger than 55 years of age.

https://www.elsevier.com/connect/how-much-coffee-is-healthy-...

Coffee industry is huge, so it's not hard to imagine that at least some of the research is fake. Also, I'm not aware of any research that explains WHY coffee has the supposed health benefits.

I like it and it doesn't seem to cause cancer, so it has those two things going for it.

Where there're sponsors there're studies. Don't trust those. Not saying that they're scientifcly wrong, but similar studies have been made for red wine and dark chocolate. Also, there was / is the green tea trend. You need to take all effects of a substance into account when judging the health benefits.

If you want to do something good for your health, drink herbal tea. But why do most of the people prefer coffee or green / black tea? Or drink red wine or eat lots of dark chocolate. Because those are stimulants.

And they are physically addicting

Woah woah woah. Did I miss the bandwagon for hating green / black tea? How are those bad? Is it just the caffiene?

45mg for black tea and 25mg for green tea

Regardless. My morning coffee may not make my life longer but it makes it more enjoyable.

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