The great medieval water myth (2013)
34 comments
·August 24, 2025raffael_de
legitster
Also, beer production started with boiling the water. So in a sense you sterilize the water and the beer helped preserve it for storage.
Watering down wine was also common in the era though, and the mechanism there implies the alcohol and acidity of the wine acted as a minor sterilizer.
legitster
This isn't really a slam dunk debunking. I get that medieval people knew about good and bad water, and that they had other reasons to prefer small drinks. But it doesn't change the facts that:
- Medieval people DID drink constantly (mostly in the form of small drinks)
- SOME medieval didn't have access to consistently good water.
- Even good water supplies can be tainted
There are cases were it was noted that a disease would outbreak from the local water supply, but no one from the brewery next door would get sick. This was not lost on most people, so water was drunk but with some risks assumed.
And most notably, we still see this exact dichotomy today in the third world where dysentery and diarrea are still common causes of death. And people with the means or preference towards prepared drinks often fare better.
kodt
The myth often states that water was unsafe to drink, so they drank beer. Suggesting water was never drank. Showing that water was regularly consumed does debunk the myth even if the truth is perhaps in the middle.
DonHopkins
“It's unpleasantly like being drunk."
"What's so unpleasant about being drunk?"
"You ask a glass of water.”
― Douglas Adams, The Hitchhiker’s Guide to the Galaxy
like_any_other
> Suggesting water was never drank.
Sounds like a straw man, or at least a weak man [1], debunked, and then the debunking is falsely applied to the whole category.
[1] https://slatestarcodex.com/2014/05/12/weak-men-are-superweap...
kodt
Perhaps, but you often see the myth written as a quick sentence or two before some beer related article. Academics may not be writing that, but lazy writers will repeat it often.
legitster
Also known as the "no true Scotsman" fallacy.
quietbritishjim
Yeah, the article text seems to suggest that beer and wine are almost never drank in preference to water (though it never quite comes out and says that explicitly). But all the quotations put water, at best, as just a reasonable competitor, not a clear winner.
niemandhier
I always assumed that it was more a case of behavior selection:
Yes, people did drink water frequently, but those societies and groups that regularly consumed fermented drinks like wine or beer, had on average a lower chance of consuming polluted water.
As a result behavior that favored drinking slightly alcoholic drinks became more widespread by selection.
This doesn’t require that people actually knew their water sources were polluted.
wat10000
This is basically the argument for respecting and following traditions even if nobody can explain why they're done.
clickety_clack
I’ve become a lot more circumspect about pushing through Chesterton fences as I’ve gained more experience in life.
I used to believe that we could determine a basis for most decisions from first principles. However, that requires a level of complete a priori knowledge that’s simply unattainable except for extremely niche situations.
mattlondon
I always thought it quite weird that somehow by virtue of being in beer, that the water somehow becomes sterilised.
If you've ever tried home brewing, you'll know that non-sterile conditions lead to foul rancid filth due to all the bacteria etc.
I'd find it odd if the people then knew to sterlise the water and equipment to make beer, but then not do the same to drink it.
eadmund
> I always thought it quite weird that somehow by virtue of being in beer, that the water somehow becomes sterilised.
The reason that water in beer is sterilised is that beer is brewed — i.e. boiled.
> If you've ever tried home brewing, you'll know that non-sterile conditions lead to foul rancid filth due to all the bacteria etc.
I believe that pre–germ-theory brewing practices tended to discourage unwanted microbial activity, in part through inoculation with large amounts of fresh barm. Did they put two and two together and connect those practices in the context of brewing to the broader context of water or food safety? Maybe.
> I'd find it odd if the people then knew to sterilise the water and equipment to make beer, but then not do the same to drink it.
Indeed, the article quotes Paulus: ‘But waters which contain impurities, have a fetid smell, or any bad quality, may be so improved by boiling as to be fit to be drunk.’
neuroticnews25
You don't really need sterile conditions, yeast just need a head start to outcompete other microbes. Then, as alcohol and CO₂ build up, the brew becomes bacteriostatic. Which is still different from being bactericidal.
raincole
The idea is by making it beer you keep safe water safe for longer. It doesn't sound particularly weird to me (I don't know if it was really a common practice in medieval Europe.)
qwytw
Before hopping and such (didn't become widespread until the 1200-1400s) beer didn't really last that long. Without refrigeration, modern bottling and almost sterile conditions in modern factories beer will go bad very fast.
sdsd
As someone who until recently had believed this myth and had never tried home brewing, the theory was that the alcohol kills the bacteria
atoav
I always understood the myth as: "When you traveled somewhere and didn't know about the water-quality, you drank beer instead".
Not that beer is immune against making you ill, but chances are random beer in some random village is better than random water in some random village, since the village people would use the good water for the beer.
ajuc
I think it's a traveling tip like "always ask for halal option - they have better ingredients" or sth.
People know beer needs specific conditions or it doesn't sell. So they are careful about that.
If you ask for water you might get the water they use for cooking soup or cleaning the mugs and they might not boil it beforehand.
wredcoll
Was there ever a serious belief that nobody drank water? That seems a bit much.
I can think of a fiction book that rather heavily pushed the idea, but it seems like a few minutes of thought would show that there's no way to produce/transport/store enough beer-type liquid for people working on a farm.
Conversely, an aristocrat/noble who travelled to a different continent might conceivably attempt to only drink beers/etc.
GolfPopper
The more common version of this, which I do remember hearing in history courses in college, was that people in the Middle Ages frequently mixed beer or wine with water. Whether that was done purely for taste, or in the belief that it would make potentially unsafe water safe, and what the details of making water safe to drink by mixing beer or wine with it actually are, I don't know. The author himself makes this point repeatedly, that water was frequently mixed with wine (at which point people are drinking watered wine).
It's like there are two parallel arguments:
"Medieval Europeans exclusively drank alcoholic beverages, because the water was so bad." And,
"We currently over-estimate the degree to which people in the Medieval-era consumed alcohol, and under-estimate the degree to which they drank pure water."
The author seems to conflate the two willy-nilly, claims the first to be widely held, and that he has disproved it (while, among others, citing Classical rather than Medieval sources).
Ekaros
Part of it I think was also that wine, but also likely beer was somewhat expensive. So adding water meant there was more liquid.
Mass production and transportation of everything at scales we have is very recent. So adding water to wine made it last longer.
swasheck
also, recalling from memory, standedge argues that the early perspective on wine was that it was simply a higher order of beer. it makes sense because there earliest beers were not hopped and would probably profile similarly to wine.
however, grape cultivation was more difficult/technical than grain cultivation which elevated the class of wine. it was also prized for its relative stability when diluted, with some maintaining the same (or better) flavor profile when diluted 1:2 water:wine. it was a true show of wealth to serve wine that was less than 1:1. (a history of the world in 6 glasses)
i’ve tried this with a few wine varietals and i can see what he’s saying in some regard, but it definitely alters the profile in ways.
sentinelsignal
Interestingly enough this is my first time hearing about this whole drinking alcohol theory and its whimsical
nritchie
This seems like an example of black and white thinking. Did they never drink water? beer? wine? Of course not. A better question - under what circumstances did they prefer beer? wine? cider? water? And later on tea? coffee? Etc?
firesteelrain
Something to ponder
Beer and wine, watered down, are medieval forms of soft drinks. People simply got tired of just drinking boring water. On top of that, you got a little buzz or it made you feel good like a soft drink might
__MatrixMan__
I heard it was a bit more... pre-medieval. More like the cause of the agricultural revolution.
https://www.scientificamerican.com/blog/guest-blog/a-sip-for...
chiffre01
I always though it was after the middle ages that alcohol was consumed for safety reasons. I also remember hearing it wasn't really the general population, but sailors on ships because water on long voyages wouldn't stay fresh very long?
rbanffy
My favorite joke derived from this misconception is that the introduction of coffee and it displacing beer as a preferred drink caused the end of the Dark Ages.
I’ll die on this hill, just because I love it so much.
aaron695
[dead]
The relevance of beer with regard to water conservation and safe consumption is _not_ because the alcohol sterilizes the fluid. It's because successfully brewed and unfiltered beer forms a relatively stable ecosystem of unproblematic yeasts and lactic acid bacteria which prevent other unsafe micro organisms to take over and multiply. The hop is actually contributing to chemical conservation, though.