r/science • u/mvea Professor | Medicine • 17d ago

Health Boiled coffee in a pot contains high levels of the worst of cholesterol-elevating substances. Coffee from most coffee machines in workplaces also contains high levels of cholesterol-elevating substances. However, regular paper filter coffee makers filter out most of these substances, finds study.

https://www.uu.se/en/press/press-releases/2025/2025-03-21-cholesterol-elevating-substances-in-coffee-from-machines-at-work
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617

u/IronicAlgorithm 17d ago

Would be interesting to know whether this holds true for Moka/steam brewing methods?

398

u/Caspica 17d ago

I don't see why it shouldn't. According to the study the paper filter filters out the substances. Moka brewers only "filters" like espresso makers, which is basically pressing the water through a metal mesh. Espresso makers were found to have high levels of these chemicals.

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u/darekta 17d ago

So why doesn't everyone in Italy have insanely elevated cholesterol? There is a Moka pot in every household.

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u/Consistent_Bee3478 17d ago

Because nutrition isn’t only ever one thing.

Also drinking litres of moka/espresso isn’t a thing. So those 2 cups espresso a day is kinda not the same as drinking a cup of coffee an hour.

And then you got the whole other nutrition around: if you don’t eat excess calories, as well as eat not highly processed foods, your cholesterol is not being elevated from food intake in the first place, compared to a diet rich in easily absorbed fats and high calories.

So any impact of cholesterol Increasing compounds in espresso will only have a minor effect.

Basically if you eat an actual well rounded and otherwise healthy diet, one ‘sin’ won’t do significant harm. 

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u/flummyheartslinger 17d ago

This post should be printed and posted in every fitness and nutrition sub. So many people focus on a single macro or even micro nutrient and miss the big picture of how things all work together.

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u/TastyTaco217 17d ago

Agreed, most people tend to look at nutrition as black and white, good or bad, when actually it’s about taking into account the 100s of different elements and weighing it out on balance.

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u/S_A_N_D_ 17d ago

Basically if you eat an actual well rounded and otherwise healthy diet, one ‘sin’ won’t do significant harm.

And one health food, "superfood", or fad that was promoted to you on Instagram can't make up for years of poor diet and chronic lack of exercise.

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u/GoldenFox7 17d ago

And that you can’t outrun your diet. People are getting a little better about this but I still hear “I just need to start running again” from people that want to lose weight, and I’ve given up explaining that eating 500 less calories of junk food is a lot easier than 500 more calories burned running.

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u/S_A_N_D_ 17d ago

I’ve given up explaining that eating 500 less calories of junk food is a lot easier than 500 more calories burned running

While that's true, being skinny but sedentary is also unhealthy.

So while it might not help you lose weight, the exercise will contribute to overall cardiovascular health, and you can be mildly overweight but in better cardiovascular health than someone who is skinny but never exercises and has a poor diet.

Though it would be better to just do both. The reality is that being healthy requires working on all the above.

1

u/Arrakis_Surfer 17d ago

So basically the headline is click bait and this substance is only concerning for people that already take risks with ultra processed food and bad habits.

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u/[deleted] 17d ago

[deleted]

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u/RunningNumbers 17d ago

It’s cheese and cured meats

21

u/house343 17d ago

Yeah but they walk everywhere instead of driving between parking lots.

1

u/Jubenheim 17d ago

Shots fired.

1

u/binkleyz 17d ago

Please tell me that nobody drinks coffee from Arby's.

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u/Iceonthewater 17d ago

It's pasta and bread with hazelnut spread

30

u/tenebrigakdo 17d ago

Notice also that they measured concentration, not whole amount consumed. Espresso and mokka coffees are drunk in very small amounts at a time, about 30-50ml. Boiled coffee in a pot is often drunk at 2dl or even more (at least in my locality). So even if both preparations contained the same concentration of harmful substances, people would have to drink 4 espressos to get to the same end amount as a single cup of boiled coffee.

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u/stupidshinji 17d ago edited 17d ago

They report that espresso has approximately 5x the concentration of the compounds than boiled coffee. The graphical abstract is accounting for serving size by using "cup' even though for espresso the serving size is much smaller. When it comes to serving size espresso is comparable to boiled coffee, i.e., even if you're drinking less you're getting similar exposure because espresso has a higher concentration.

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u/tenebrigakdo 17d ago

They note a large range for espresso. I think this is something that warrants more research.

1

u/TotallyDissedHomie 16d ago

Was that 4 data points? I didn’t read it but the graph is odd with solid bars and some data points

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u/Emberwake 17d ago

And 5x a miniscule amount is still an insignificant amount.

Coffee is simply not a high source of cholesterol no matter how you brew it or how much you consume.

3

u/stupidshinji 17d ago

1) I never claimed that it is a lot. My point was that the comment above mine erroneously claimed that espresso and boiled coffee have the same concentration of these compounds, which is not remotely true based on the reported findings. They have a similar amount based on serving size. Espresso shots are smaller in volume, but higher in concentration resulting in approximately similar levels per serving.

2) The paper isn't discussing cholesterol in the coffee. Studies have shown that dietary cholesterol does not heavily influence a person's cholesterol levels. What this paper is reporting is compounds that are known to impact a person's cholesterol levels.

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u/Emberwake 17d ago edited 17d ago

The paper isn't discussing cholesterol in the coffee.

No, it is discussing the relative concentration of "cholesterol increasing compounds."

But the issue remains that the volume of "cholesterol increasing compounds" found in even an extreme amount of coffee is dwarfed by a single serving of butter.

This whole topic is blown out of proportion.

EDIT:

I would like to apologize. I clearly did not communicate well and may have given offense as a result.

I understand that you were not discussing the significance of these amounts of cholesterol increasing compounds. It was never my intention to dispute the accuracy of your comment, but rather to question the relevance of the entire issue. This probably could have been its own parent comment, and I understand if you felt unfairly targeted.

If you would like me to remove my comments, please let me know and I would be happy to do so. Either way, I hope you have a good day!

3

u/Ranessin 17d ago

Hides the 500 ml "10 servings" Mokka pot used for making two cups in the morning.

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u/friendlyfredditor 17d ago

Yea I'm super weirded out they didn't convert it to a "per serve" value. All their brewing methods utilised different doses of coffee (7-21g) and they had no knowledge of the espresso coffee dose and I'm assuming they didn't dilute it at all.

Among the coffee community espresso is known for a pretty medium level of extraction compared to brewing methods that take a longer time like drip.

An espresso shot starts with 2-3x the amount of coffee they used in their filter method and is diluted 6 to 10x more for a standard long black/americano or milk drink. Their espresso concentrations are inflated anywhere from 12x to 30x.

Just as a further anecdote the coffee grounds themselves act as a high resistance filter for espresso otherwise you wouldn't be able to generate 9bar of pressure.

1

u/thongs_are_footwear 17d ago

The use of deciliter (dl) is quite uncommon.
Was there a reason you decided on this unit of measure?

1

u/Rambus_Jarbus 17d ago

Lots of walking.

1

u/YetAnotherDaveAgain 17d ago

Very fine coffee actually makes a surprisingly good filter. But espresso and moka pots (and especially French press!) both do contain more of those compounds than filter coffee.

Perhaps part of it also dose. I'd be curious to know the actual amount of coffee beans (in grams) that Italians consume versus Americans. A lot of their commercial shots are single shots, if I recall correctly (ie 8-10 grams versus Americans more typical 16-20 gram doubles). But that definitely could be wrong....

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u/Mrqueue 17d ago

Because it’s click bait 

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u/DearLeader420 17d ago

Because Italians have a far better diet than many other Western nations, and they walk a lot more.

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u/iamjacksragingupvote 17d ago

countered by olive oil, prob

26

u/EuphoricLettuce 17d ago

According to the study percolator and french press coffee had low levels of the substances so one could extrapolate that moka pots aren't much worse than those methods.

https://ars.els-cdn.com/content/image/1-s2.0-S0939475325000870-ga1_lrg.jpg

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u/Butterflyelle 17d ago

Thank you for linking to the graph. I was curious about cafetiere coffee as that's what I drink but seems that's low too. It must be a large molecule they filter out because compared to paper the metal mesh is pretty coarse that's used in a cafetiere. The fabric filter looks like a Christmas stocking- anyone know what it's supposed to be?

10

u/The_Revisioner 17d ago

The fabric filter looks like a Christmas stocking- anyone know what it's supposed to be?

Literally a "coffee sock". Cotton or linen in the shape of a tube that holds the grounds while you pour the mix or hot water through it. Reusable.

7

u/SophiaofPrussia 17d ago

If you search “Thai tea strainer” or “Thai coffee filter” you can find them. It’s just a cotton tube, usually with a rim & handle, that you use similar to the way you’d use a paper filter for pour-over coffee except, unlike a paper filter, it’s reusable.

3

u/3DBeerGoggles 17d ago

Interesting that percolators and french press units were no where near as bad. I wonder if that's because boiling (and espresso) are more vigorous and freeing up more of the oil into solution.

1

u/TheGreatRandolph 17d ago

I would have gone with temperature since french pressure and other coffee is better a little below boiling, except a perc relies on keeping the water at a boiling temp. Hmmm…

1

u/3DBeerGoggles 17d ago

Yeah, it's an interesting question - espresso involves high pressure water, perhaps that's why it's similarly effective at "cracking" the oil out of the ground coffee as boiling.

1

u/Dokterrock 17d ago

I notice that coffee from the moka pot irritates my bladder more, so I started making it there and then pouring it through a paper filter. I think it tastes better than just drop coffee, but I could be fooling myself.

1

u/Reddit_from_9_to_5 17d ago

ty for the link!!

18

u/DominusValum 17d ago

I use these paper filters for my moka pot that apparently are supposed to filter that stuff out a bit. I notice a difference when I use it or dont

9

u/forams__galorams 17d ago

What kinda difference are you noticing? Taste? Texture? The way you feel afterwards?

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u/DominusValum 17d ago

Should have been more specific. There is definitely a less filmy quality, like some oils in the drink were absorbed. It's a smoother cup of coffee too, less of the 'sludge' kind of feeling from it.

2

u/passenger_now 17d ago

Mostly to me just the obvious - with filter it's clearer, without it's more murky, in look, feel and taste. How much I'd notice it if I tasted it blind is another question, but I detected a more subtle version of the same when blind-comparing Aeropress with pour-over (forced through the filter vs gravity drip).

Personally I prefer the clarity, so combined with probable health benefits I'm all about the filter.

1

u/Spiritual_Calendar81 17d ago

What if you use those circular paper filters in your espresso portafilter?

1

u/gbcfgh 17d ago

Mesh basket only, I can see that. I wonder if the paper wrappers used for E.S.E. (Easy Serving Espresso) pods are sufficient for filtration, or if the 15bar pressure used counteracts the filtration through sheer power of will.

1

u/oneoftheryans 17d ago

They had other non-paper filtered options that weren't anywhere near as high as the boiled option in the relevant compounds, so you might be surprised.

https://www.sciencedirect.com/science/article/pii/S0939475325000870?via%3Dihub

https://ars.els-cdn.com/content/image/1-s2.0-S0939475325000870-ga1_lrg.jpg

1

u/ClamClone 17d ago edited 17d ago

I started making paper filters out of Chemex filters with a 2.25 Friskars paper punch that fit perfectly into a standard E61 portafiltre. Each Chemex sheet makes 16. I think I might need to start using two instead of one to catch the the problem components better. One box of 100 filters is about $10 so less than a penny each. That is so much cheaper than the ready made ones.

1

u/faximusy 17d ago

There is a built-in filter in the moka to keep the coffee out. Also, the water has to reach the top of the funnel and may be losing even more material in this way. I would not be so conclusive without actually testing it.

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u/apostasyisecstasy 17d ago

I have some health issues that means my doctor monitors my cholesterol pretty closely. I had my annual lipid panel done and my cholesterol was sky high after having perfect numbers previously, my doctor and I have been desperately trying to figure out how this happened. I've even been referred to a nutritionist. No changes to diet or exercise, if anything I've been more active and eating better. I did, however, get a moka pot six months ago.... I think I just solved the mystery.

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u/CuriousCursor 17d ago

Give us an update after your next test!!

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u/Kryhavok 17d ago

Curious to see where mine goes too. I've always had low cholesterol but after getting a little fat I'm trying to cut soda and sugar. I switched to coffee to help with this, and I've been french pressing about 16oz a day. I'll find out in about a year if my choesterol gets worse.

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u/no_arguing_ 17d ago edited 17d ago

Husband and I have been French pressing twice a day for 8 years now and both our cholesterol levels are consistently low. Maybe some people are more sensitive, but you'll probably be fine. It's probably a drop in the bucket relative to other dietary factors. Also the method in this particular study was said to be way worse than French press (likely due to over extraction).

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u/Kryhavok 17d ago

Cool glad to hear that.

4

u/Anxious-Tadpole-2745 17d ago

Some people are more sensitve than others!

2

u/Ordinary-Steak-6515 17d ago

My cholesterol went sky high when I started using a French press. It took me about a year to figure out this was the cause. Now it’s fine again after switching back to filtered coffee.

1

u/peoplearecool 17d ago

My bufdy drinks from moka every day sometimes 2x for years. His cholesterol is optimal. Maybe there is a genetic componebt to being susceptible to these chemicals?

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u/apostasyisecstasy 17d ago

I just covered this in another comment, summary: I'm super duper genetically predisposed and I have other contributing health issues. My husband drinks the same coffee as me, is not predisposed, and has only had a slight elevation in cholesterol.

0

u/Cicer 17d ago

The coffee filter cholesterol link has been known for years. If your Dr and nutritionist didn’t suggest it as a possibility it might be time to seek new healthcare. 

6

u/apostasyisecstasy 17d ago

Bless you for it not occurring to you that I was the idiot in this situation, but no my doctor really did her due diligence. The fault was mine for it not occurring to me that my moka pot counted as what she was talking about.

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u/HistoryNerd 17d ago

There are paper filters used with moka pots. Not everyone uses them but it does improve the texture of the coffee. I highly recommend using them if you do not.

French press on the other hand maybe more of a concern since it's just a wire mesh.

22

u/TripleSecretSquirrel 17d ago

Ya, goddammit, I love my French press and part of the reason was specifically to avoid the paper waste of using a filter every time.

1

u/sprunkymdunk 17d ago

Have you tried just using instant? Ducks

8

u/baldycoot 17d ago

Espro French presses have two baskets, designed in a way to take regular paper filters between them.

Easily my favorite French presses (and I’ve thrown a lot away.)

2

u/Eragaurd 17d ago

You can also simply wet a round coffee filter and stick it to the metal mesh of a normal french press.

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u/Ludwigofthepotatoppl 17d ago

They make paper percolator filters too.

1

u/Butterflyelle 17d ago

The graph suggests French press is low confusingly

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u/fuchsgesicht 17d ago edited 17d ago

wasn't there a study that these paper filters add a lot of microplastic to the brew? (i think the example was tea bags)

Edit: https://pmc.ncbi.nlm.nih.gov/articles/PMC10389239/

1

u/IronicAlgorithm 17d ago

Will try them, thank you!

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u/HistoryNerd 17d ago

My recommendation for using them is that you put the paper filter on the bottom of the upper reservoir-- use a little bit of warm water to get it wet so that it sticks to the metal filter side rather than trying to fit it on top of your grounds. It just seems to work so much better. Good luck!

2

u/AbareSaruMk2 17d ago

Ooo. Thanks for the tip. I have some filters from my aeropress. Shall give them a go in my Moka pot in the morning.

4

u/Slamyul 17d ago

That's what I use, worked perfectly for me. Just make sure your grounds aren't too fine or packed, as the filter adds some resistance, increasing the pressure.

1

u/IronicAlgorithm 17d ago

When I purchased some filters, this was the issue I had. On top, the coffee would not brew properly, I thought the pot was going to explode! Will try this method.

1

u/patcriss 17d ago

As a recent moka pot owner, thanks. This saved my purchase. There were insane levels of sediments (even with coarser grind) and paper filters completely fixed my only issue with my moka pot.

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u/wagonspraggs 17d ago

Yes, most of the studies looking at blood pressure increase from boiled vs filtered included moka pots in the boiled coffee category. Note that boiled coffee increases blood pressure while filtered coffee dies not, according to the three studies (I think there's more now though).

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u/passenger_now 17d ago

Weird way to put it, as the coffee is not boiled in anything but a percolator or turkish or cowboy coffee. I've seen studies of filtered vs not filtered, but haven't heard people talk about boiled coffee before and I'd never have assumed it applied to Moka. In that case it would apply to espresso too.

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u/RunningNumbers 17d ago

Harvard Medical School has a whole literature review on the coffee oils and cholesterol stuff, It is one of the good causal food studies out there (easy to RCT.)

Paper filters catch the oil but let the caffeine brown through.

-1

u/DervishSkater 17d ago

No it doesn’t say what you think it says

https://www.health.harvard.edu/staying-healthy/whats-the-healthiest-way-to-brew-coffee#:~:text=The%20study%20is%20observational%20and,a%20cup%20of%20filtered%20coffee.

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u/marxr87 17d ago

that link appears to say exactly what they said it says...

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u/Objective_Kick2930 16d ago

Why would you think a Harvard Health news brief on a study in the European Journal of Preventive Cardiology  has anything to do with a Harvard Medical School literature review of existing literature on the topic?

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u/tenebrigakdo 17d ago edited 17d ago

I've seen other studies that touched this topic (although not to this level of detail) and they showed that coffee where water doesn't stand on the beans for prolonged time (so espresso, mokka, etc) is has no effect on cholesterol level. Also anecdotally, my husband's cholesterol levels dropped after we switched to mokka. I don't know about cold brew though, I haven't seen any study mention it.

Edit: I've looked at the study more closely and I think a 'percolator' and mokka pot are the same thing, or very close. They got intermediate results for both the researched substances (boiled coffee about 900 mg/l and 700 mg/l, percolator 90 mg/l and 70 mg/l, paper-filter coffee about 12 mg/l and 14 mg/l).

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u/st8odk 17d ago

cold brew is less acidic

2

u/Mabon_Bran 17d ago

When I bought a mokka pot, out of curiosity, I watched some coffee enthusiasts YT video. And a lot of them advised on using a one use coffee filter that you place on top of metal mesh. So I bought them on bulk, as they are pretty cheap. I still have them. They are not a hassle to put on.

2

u/Shot-Werewolf-5886 17d ago

I'd like to know if it holds true for instant coffee as well. I switched to instant coffee years ago when my regular coffee pot broke during a move and I just never went back because instant tasted fine and I enjoyed not having the extra cleanup and having to buy filters.

2

u/awarmlight 17d ago

We have used a moka pot for years. The first year after we got it my cholesterol spiked. Hubbie did some research and found a small study from ages ago that had the same results as this one. Got some little paper filters for my moka pot and cholesterol went right back to normal. Did not change anything else. Anecdotal completely. No clue where he found the citation unfortunately.

2

u/IronicAlgorithm 17d ago

Those paper filters seem to be the way to go. Will try them out!

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u/Rob_Zander 17d ago

I read the article and it seems like anything where the coffee is metal filtered has higher concentrations of those chemicals but it seems that higher temperature methods correlate to higher concentrations. So a French press at 200F is likely to have a lower concentration than something brewed at 212 and metal filtered.

Apparently boiled coffee is just a common way of making coffee in Sweden and is literally just coarse ground coffee, cold water and brought to a boil. Which unsurprisingly has the highest concentrations but if strained through a paper filter has less.

1

u/Shimaru33 17d ago

I would be more interested in knowing if brewing the coffee as normal, then filtering through a paper would help to remove those substances? I suppose the answer would be yes, and not many people wanting to add an extra step in their favourite method, but for those with heart conditions...

1

u/Narwahl_Whisperer 17d ago

I've been doing french press lately, I'm wondering the same thing.

1

u/EuphoricLettuce 17d ago

From the study percolator coffee was relatively low in levels of diterpenes (the cholesterol-elevating substances) so i would assume it would be similar to percolator and or espresso.

Here is a link to the chart they use to show the different levels of diterpenes: https://ars.els-cdn.com/content/image/1-s2.0-S0939475325000870-ga1_lrg.jpg

1

u/delicious_fanta 17d ago

I guess my coffee ice cream is doing terrible things to me.

1

u/Mr_Mayamar 17d ago

The study refers to them as “percolators” which showed lower levels of cholesterol substance’s

1

u/hfsh 17d ago

Percolators are a different thing than mokka pots, though people conflate them a lot. And the graphic in the paper strongly suggests they tested an actual percolator, rather than a mokka pot.