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.

[u/mvea]

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

[u/AutoModerator]

Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, personal anecdotes are allowed as responses to this comment. Any anecdotal comments elsewhere in the discussion will be removed and our normal comment rules apply to all other comments.

---

Do you have an academic degree? We can verify your credentials in order to assign user flair indicating your area of expertise. Click here to apply.

---

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

---

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/coco-ai]

I don't even know what boiled coffee in a pot means! It's certainly not common in Australia.

[u/travelnman85 → u/coco-ai]

It's how I make it when camping. In the USA this method is often referred to as cowboy coffee.

[u/mattne421 → u/[deleted]]

No just boiling water in a cup. Add your coffee grounds. Stir and let the grounds settle. Sip cautiously.

[u/scarabic → u/mattne421]

All Turkish coffee is made that way. Must be terrible for cholesterol levels in the Middle East.

[u/SoldnerDoppel → u/scarabic]

Sultan Murad IV was actually just concerned for his subjects' cardiovascular health.

[u/dallyan → u/scarabic]

Tbf Turks don’t drink as much coffee as westerners. Tea tends to be our morning and throughout the day drink. Coffee is more of an after lunch or after dinner treat. Definitely not drunk in the morning.

[u/Baskreiger → u/mattne421]

Like in a french press?

[u/YouAreNotYouYoureMe → u/Baskreiger]

I use a french press and pour water that is either boiling or just boiled into it, am I kaput?

[u/Delphinethecrone → u/YouAreNotYouYoureMe]

Me too. It's worth it.

[u/toosells → u/Delphinethecrone]

That's the whole reason to use a French press. The oil on top.

[u/cosmicmermaid → u/Baskreiger]

I actually learned from the cholesterol subreddit (some very knowledgeable folks there) about unfiltered coffee possibly elevating levels; I drank so much French press! So, I (begrudgingly) gave that up and also followed the recommendation of lowing saturated fats in diet and got my numbers significantly reduced!

[u/Dozzi92 → u/Baskreiger]

That's what's coming to mind for me. I had to quit french press, for some reason it just stopped sitting right. I'm a drip through bamboo filters kinda guy now.

[u/jackiemelon → u/Baskreiger]

This makes sense, I've always been under the impression (pun unintended) that a French press is the worst way to make coffee for cholesterol

[u/DamnitColin → u/jackiemelon]

I wonder if cold brew in a French press is better?

[u/7i4nf4n → u/mattne421]

You actually add after boiling a bit of cold water, so the ground coffee sinks, and after that you can pour it into a cup. If you do it without moving the pot too much, the grounds will stay at the bottom and you have very little loss

[u/k3liutZu → u/7i4nf4n]

Or like my mother calls it: you scare the coffee with cold water!

[u/Xe6s2 → u/k3liutZu]

That sounds wholesome

[u/Triassic_Bark → u/7i4nf4n]

You add what after boiling a bit of cold water? Why does the water have to be cold before you boil it?

[u/7i4nf4n → u/Triassic_Bark]

"You actually add (after boiling) a bit of cold water [to the pot with your boiled coffee] [...]"

Better?

[u/xTRYPTAMINEx → u/7i4nf4n]

Yes. Much legible, such read, wow

[u/jafjaf23 → u/7i4nf4n]

Yes, thank you

[u/Ludwigofthepotatoppl → u/7i4nf4n]

You can also mix the grounds with a whole egg (shell and all) and boil it the same way, cold water as usual to help settle it.

[u/Rickshmitt → u/Ludwigofthepotatoppl]

At first, my stupid brain thought you meant smash the egg up with the shell, and somehow, it'll bond with the grounds and keep them from free floating. Gross brain

[u/Sideyr → u/Rickshmitt]

Your stupid brain was the smarter brain in this instance.

https://www.thespruceeats.com/egg-coffee-2952648

[u/wheatgivesmeshits → u/Sideyr]

Thanks for the link, but the coffee in the before and after from that video is not what was made during the video. It's sad that content creators do things like that.

[u/A_Mouse_In_Da_House → u/wheatgivesmeshits]

Spruce eats does that all the time. It's great

[u/Pleasant-Shallot-707 → u/mattne421]

If your percolator uses a metal basket with some small holes punched in it and you don’t use a paper filter then I presume it’s the same effect and boiling it.

[u/PicoDeBayou → u/Pleasant-Shallot-707]

What are you some kind of boilingtologist?

[u/WAPWAN → u/mattne421]

That is the standard method of drinking coffee in Indonesia, Kopi Tubruk

[u/cultoftheclave → u/WAPWAN]

same with mexico, café de olla. sometimes spices added in, and lots of raw sugar.

do Indonesians have unusually high cholesterol vs other groups? México has this problem.

[u/HeKnee → u/[deleted]]

Percolator, french press, basically anything not filtered. This has been known for at least a decade.

[u/EnBuenora → u/HeKnee]

Strangely, french press and percolator had much lower levels of the two substances in question than this (for the article) Nordic boiling method.

[u/Dabbling_in_Pacifism → u/EnBuenora]

A proper glass of French Press isn’t made with boiling water, but just under it. Wonder if that matters.

[u/EnBuenora → u/Dabbling_in_Pacifism]

No idea, but even passing the boiled coffee through a fabric filter greatly reduces the two substances linked to higher bad cholesterol levels.

[u/300Savage → u/EnBuenora]

French press at least doesn't have the long boiling period that cowboy coffee does. I'm not sure why perced coffee would be lower but possibly because the water is lower than boiling temperature by the time it rises up the percolator onto the grounds?

[u/Ludwigofthepotatoppl → u/HeKnee]

They make percolator filters, too! Percolator coffee with easier cleanup and no grit.

[u/thelimeisgreen → u/HeKnee]

Yes, been known for a long time. And you can have my French press when you pry it from my cold dead hands.

[u/ihadagoodone → u/thelimeisgreen]

I have thousands of dollars of coffee brewing equipment.

My $20 French press is my go to method.

[u/veringer → u/thelimeisgreen]

My thoughts too: "Welp, I guess I'll have higher cholesterol because definitely not ditching the French press"

[u/Tall_poppee → u/HeKnee]

I heard this about using a paper filter in the 90s.

Even in my espresso machine, I'd add little circles of filter paper cut to the right size, under the metal basket. High cholesterol runs in my family but we also love our coffee. Now I do pour-over, and the paper filters go right in the compost pile with the grounds.

[u/moonscience → u/travelnman85]

Also a french press...used one of those for years.

[u/Androne → u/moonscience]

But you're not suppossed to put boiling water in a french press. It should be around 90-95 degrees celcius.

[u/JUYED-AWK-YACC → u/moonscience]

No, you aren't boiling coffee in the French press. You put hot water into it just like every normal way.

[u/bitemark01 → u/coco-ai]

For what it's worth, I have a regular old drip coffee maker, and I had been using a metal filter basket instead of paper for about 10-15 years, because I thought it was less wasteful. 

I got curious about what was being filtered and not filtered, so I put a paper filter underneath the metal filter. 

It catches a LOT of stuff that the metal filter doesn't, I never realized. It's like a thick particle oil. 

Anyway I switched to a paper filter after that because I did some reading and found out that oil does indeed raise cholesterol. Incidentally some mild psoriasis I've had on/off issues with got better after the switch.

[u/janyk → u/bitemark01]

I used to use those metal filters but then I could see the oil in my coffee. If you swirled the coffee in the cup a bit, you could see a film sticking to the sides of the cup that moves a bit slower than the rest of the coffee. I could also taste it, too, and I didn't like it. More bitter, I think.

Switched back to paper filters and I got a clean cuppa joe now

[u/bitemark01 → u/janyk]

Haha yeah I could see it too, especially once you get to the bottom. I was hoping it was giving me more kick! 

Can't say I've noticed less kick since switching. Does taste better though.

[u/Biosterous → u/bitemark01]

Ok so now I'm interested in if this holds for Moka pots and Neapolitan coffee makers since they only use metal filters.

[u/oneoftheryans → u/bitemark01]

If it makes you feel any better, that seems likely to be only slightly worse than the drip paper-filtered coffee.

French press and percolator brewing options were also tested, and they're like 10x lower in cafestol and kawheol than the coffee grounds + boiled water option.

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

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

There's a lot of "stuff" in unfiltered coffee, but based on the boiled result and the variance with espresso, it kind of seems like the increased cafestol and kawheol levels might be a result of over-extracting the coffee.

[u/radix89 → u/coco-ai]

Do you have percolator coffee there? In the US we made it on the stove or when camping. Europe probably used a stand alone kettle type but I'm not sure those are common for you either. I'm only familiar because my aunts always made it this way for crowds.

[u/coco-ai → u/radix89]

It's very rare, I am mostly familiar with that style of coffee from American television tbh. It's probably in this order of most common to least: espresso, pod machines, french press, stove top Italian percolator (can't remember the name of those, they bubble up on the inside). Instant is probably as popular as espresso but with a very different crowd!

[u/Plebs-_-Placebo → u/coco-ai]

Moka pot, although my partner's family all call it espresso and they're Italians

[u/rawarawr → u/coco-ai]

It's european (mostly balkan) way of making coffee. We have small little pots just for coffee. You can google "džezva" and you'll get it. Preparation is very easy: You boil water, put 2 spoons (or how much you want) of ground coffee and boil again for a few seconds so the coffee raises and you're done.

[u/paulerxx → u/coco-ai]

"Cowboy coffee" is what I heard it described as many times throughout the years.

[u/rustyphish → u/coco-ai]

Yeah I’m confused. Who’s making a pot of coffee without a filter?

Edit: folks I know what a French press is, if you’ll notice the title refers explicitly to “workplace coffee machines”. I wasn’t aware in other countries that these machines don’t use paper filters like they do in the us

[u/hyldemarv → u/rustyphish]

Sweden, "Kokkaffe", 1 person:

One puts about 10 g of coarsely ground coffee in a pot, add 1.5 dl water*, mix it up and and heat the mixture until it almost boils, take it off the fire and mix it up again, then let the pot stand for about 7 minutes. The coffee grounds should now have settled at the bottom and one can pour most of the coffee into a cup without getting any.

Used to be "the way" before the 1960's. Today, it's more a traditional way to prepare coffee when one is staying in the forest, f.ex..

There is some controversy about whether one should put the coffee into the water when the water is cold, or one should heat the water first. I prefer to add the coffee to the cold water.

*) One brings a measuring spoon that gives 10-12 gram per measure. Camping pots often have dl lines inside.

[u/erevos33 → u/hyldemarv]

Irrelevant question, when did f.ex. become the norm instead of e.g.? I have seen it popping up here and there.

[u/Eragaurd → u/erevos33]

I don't know about norm, but I'm assuming the person above is Swedish, and here we shorten "till exempel" to "t.ex.", which directy translated would be "f.ex". So I'm guessing it's simply a case of direct translation from Swedish to English.

[u/RunningNumbers → u/hyldemarv]

I just remember the uncivilized coffee machine that everyone used at work when I lived in Denmark. Terrible acrid sludge. And they were like “this is fine.”

Barbarians should have stuck to raiding monasteries.

[u/Parafault → u/rustyphish]

Isnt that the whole point of a French press? The steel filters in those are probably too big to remove any of this stuff.

[u/rustyphish → u/Parafault]

But they’re saying “most workplace machines”, I’d think that wouldn’t account for things like a French press

[u/zxern → u/rustyphish]

Probably talking about the giant percolator pots that make 40 cups at a time and store it in the pot.

[u/KingAdamXVII → u/zxern]

Those ones have filters, I thought?

Ah, from the article: “Considering how much coffee is consumed in Swedish workplaces, we wanted to get a picture of the content of cholesterol-elevating substances in coffee from these types of machines.”

[u/greiton → u/KingAdamXVII]

not the big drum ones, they just have a metal sieve between the boil chamber and the reservoir.

[u/KingAdamXVII → u/rustyphish]

Ah, from the article: “Considering how much coffee is consumed in Swedish workplaces, we wanted to get a picture of the content of cholesterol-elevating substances in coffee from these types of machines.”

And elsewhere in this thread someone mentions this is how coffee is often made in Sweden.

[u/impossiblefork → u/KingAdamXVII]

Usually Swedes make coffee with a coffee machine with a filter.

The pot method is as far as I understand completely historical. No one uses it other than on like a hike or something.

[u/badsp0rk → u/rustyphish]

Turkish coffee. Greek coffee. I think Cypriot, too? Ethiopia? Many places just boil the ground beans and consume that - it's common in the middle east and around. It leaves a thick residue at the bottom.

[u/pax27 → u/badsp0rk]

The study is Swedish and it's common to boil your coffee in a pot here. Or it used to be, especially in the northern parts of Sweden. It's probably falling out of fashion now that everything needs to be fancy as hell.

[u/Long-Challenge4927 → u/rustyphish]

I think that's how coffee was originally made before technical improvements. Still made like this in a lot of places, check middle eastern coffee, turkish coffee etc. Been to Balkans, they boil it in a small pot

[u/PoorlyAttired → u/rustyphish]

This applies to coffee made without a paper filter, like the metal grill in a French press. The paper (like in an aeropress or drip filter device) absorbs the cholesterol raising oils that the metal mesh lets through.

[u/JoeSabo → u/coco-ai]

Cowboy style!

[u/LibranJamess]

I work with the author of this paper. I just showed him this. He doesn’t have reddit but he’s going to create an account to answer some of the questions! Awesome job dr Erik & co

[u/raunchyfartbomb → u/LibranJamess]

Here’s a question for him: would a paper filter in a percolator reduce the levels?

Something like this (which I use every time, because it reduces the grounds in the coffee)

https://a.co/d/09IEGF8

[u/FamousAmos00 → u/raunchyfartbomb]

According to the study, yes

[u/Therinicus → u/raunchyfartbomb]

Great question

[u/Reddit_from_9_to_5 → u/LibranJamess]

Can you ask him if French Press qualify for this (due to pouring boiling water with the beans), or just Mokka pots?

Wondering if it's the act of water reaching its boiling point, the heat of the boiled water, or the general mechanism to filter the beans in these devices (often a metal mesh or metal percolator) that contributes to the cholesterol-elevating substances

Edit: nevermind, saw this graph in the paper itself showing French press is *relatively* fine https://ars.els-cdn.com/content/image/1-s2.0-S0939475325000870-ga1_lrg.jpg

[u/ipiercemycow → u/[deleted]]

Commenting for a follow up too, but I had the same question as you!

I’m also curious about different brands of machines and whether that can be ‘exposed’ or not.

[u/DataVonTease → u/LibranJamess]

Question: where do reusable metal filters fall in this?

[u/MoneybagsMalone → u/LibranJamess]

Espresso? I'm presuming high temp and pressure having the same issues as boiling?

[u/Lvl100Magikarp → u/LibranJamess]

What about instant coffee?

[u/octopusboots → u/LibranJamess]

He should do an ama.

[u/pineapplecatlady24 → u/LibranJamess]

What about nespresso pods?

[u/apoletta → u/LibranJamess]

Cool! If we can get more information regarding instants that would be lovely.

[u/IronicAlgorithm]

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

[u/Caspica → u/IronicAlgorithm]

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.

[u/darekta → u/Caspica]

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

[u/Consistent_Bee3478 → u/darekta]

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. 

[u/flummyheartslinger → u/Consistent_Bee3478]

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.

[u/TastyTaco217 → u/flummyheartslinger]

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.

[u/S_A_N_D_ → u/Consistent_Bee3478]

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.

[u/GoldenFox7 → u/S_A_N_D_]

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.

[u/RunningNumbers → u/[deleted]]

It’s cheese and cured meats

[u/house343 → u/RunningNumbers]

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

[u/tenebrigakdo → u/darekta]

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.

[u/stupidshinji → u/tenebrigakdo]

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.

[u/EuphoricLettuce → u/Caspica]

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

[u/Butterflyelle → u/EuphoricLettuce]

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?

[u/The_Revisioner → u/Butterflyelle]

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.

[u/SophiaofPrussia → u/Butterflyelle]

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.

[u/DominusValum → u/Caspica]

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

[u/forams__galorams → u/DominusValum]

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

[u/DominusValum → u/forams__galorams]

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.

[u/apostasyisecstasy → u/IronicAlgorithm]

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.

[u/CuriousCursor → u/apostasyisecstasy]

Give us an update after your next test!!

[u/Kryhavok → u/apostasyisecstasy]

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.

[u/Anxious-Tadpole-2745 → u/apostasyisecstasy]

Some people are more sensitve than others!

[u/HistoryNerd → u/IronicAlgorithm]

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.

[u/TripleSecretSquirrel → u/HistoryNerd]

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.

[u/baldycoot → u/HistoryNerd]

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.)

[u/wagonspraggs → u/IronicAlgorithm]

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).

[u/RunningNumbers → u/IronicAlgorithm]

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.

[u/tenebrigakdo → u/IronicAlgorithm]

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).

[u/SeyiDALegend]

I wonder how French press coffee factors into this

[u/heteromer → u/SeyiDALegend]

The French press and percolators had around 3 times the amount of diterpenes than filtered coffee, although it was still much lower than unfiltered coffee.

[u/itwentok → u/heteromer]

Yep, here's the relevant table from the research paper: Table 1 Concentrations of diterpenes cafestol and kahweol in different coffee brews (mg/L).

[u/Dhun101 → u/itwentok]

Oh no. Is espresso the worst?

[u/thegooddoktorjones → u/heteromer]

Does cold brew press have the same levels?

[u/DessertTwink → u/thegooddoktorjones]

I've only made cold brew in a commercial setting for coffee shops, but those coffee grounds are contained within a sealed paper bag or a cheese cloth. Those same cholesterol raising compounds shouldn't be produced since they're steeped in cold water for an extended period of time (20hrs minimum is pretty standard) but even if they did, the bag would be acting the same as a paper filter for drip coffee and prevent those chemicals from making it into the final product.

[u/thegooddoktorjones → u/DessertTwink]

My wife does it at home in a French press, I believe the water is hot when initially added, then pressed down then it rests in fridge for a day. No cloth or filter, just the press. Not an expert on it though.

[u/DessertTwink → u/thegooddoktorjones]

That would no longer be cold brew, then. That's just iced coffee. A strong iced coffee since she's letting it sit, but still iced coffee. The cold water extracts the caffeine and flavor from the coffee beans differently than if you hit it with hot water first. Cold water-only produces a less acidic brew with a smoother flavor.

It's like using softened butter vs melted butter when making cookies. The latter results in a thinner chewy cookie, while the former will be pillowy and lighter in texture. Same ingredients, but the result is different.

[u/Safe-Particular6512 → u/thegooddoktorjones]

Cold brew coffee is started with cold water - Not hot.

[u/Sethjustseth → u/SeyiDALegend]

I already posted this, but it's relevant to your question: All I know is I had high cholesterol and one of the many steps I took was going from French press to paper filtered pour over coffee and I saw a 40% cholesterol reduction in 7 months. I'm sticking with filtered coffee.

[u/vadan → u/Sethjustseth]

I saw similar cholesterol reduction within 3 months and all I did was pour the French pressed coffee through a paper filter after the steep.

[u/mattcraft → u/[deleted]]

I'm not the commenter who you were asking, but there was previous information that unfiltered coffee was potentially more carcinogenic than paper-filtered coffee. There are flavor/aroma pros and cons as well, but I'm too casual to speak to that. Point being is that I heard this information from at least two co-workers years before coming upon this post now. It pushed me toward using the aeropress instead of french press (although one of the co-workers mentioned adding a paper filter to the french press).

[u/Aquaintestines → u/[deleted]]

Bought and paid for by Big Filter

[u/quackerzdb → u/Sethjustseth]

That's a huge change. Did you also start taking statins at the same time? 40% is about what you get from standard cholesterol medication.

[u/Sethjustseth → u/quackerzdb]

Nope, I'm already vegetarian and exercise daily, but I cut way down on cheese, butter, and chocolate, switched to fat free yogurt, cut out palm oil from peanut butter etc., filtered my coffee, and just trying to keep the saturated fat under 10 grams a day if possible. LDL went from 156 to 96 which my doctor called extremely impressive. Glad I don't need medication yet!

[u/randylush → u/Sethjustseth]

I cut way down on cheese, butter, and chocolate, switched to fat free yogurt, cut out palm oil from peanut butter etc., filtered my coffee,

Given those other massive changes I’m not sure how much you can realistically attribute your lowered cholesterol to filtered coffee

I’m curious though, did you start filtering coffee with the intention of lowering LDL? Was that something a doctor told you to do? Was this link widely known?

[u/quackerzdb → u/Sethjustseth]

That is really impressive. The studies I've seen only see about 10% reductions from diet alone, but you seem very committed and disciplined. Good on you.

[u/p4rk_life → u/quackerzdb]

You are correct, dietary sourced cholesterol is only a small factor, nick norowitz has several studies and videos explaining the mechanism recently discovered. His 720 eggs or oreos lower ldl are the most popular, but the science behind the process illustrate dietary cholesterol is moderated by a chemical feedback mechanism

[u/squad1alum → u/SeyiDALegend]

Among the poorest at filtering out the mentioned cholesterol raising substances.

[u/BrownByYou → u/squad1alum]

What if you made it in a French press but then poured it through the white filter paper we use in machines?

[u/JksG_5 → u/BrownByYou]

It will likely reduce the amount of substances.

[u/Mechasteel → u/SeyiDALegend]

The French press has a roughly 10x reduction, and paper-filtered coffee a 78x reduction, vs boiled unfiltered coffee.

...estimated LDL cholesterol to increase 0.0104 mmol/L per mg cafestol, and 0.0016 mmol/L per mg kahweol daily ingested. [...] The median (range) cafestol and kahweol concentrations were 176 (24–444) mg/L and 142 (18–434) mg/L for brewing machines (n = 11), 8 (2–343) mg/L and 7 (2–288) mg/L for liquid-model machines (n = 3), and 12 (4–24) mg/L and 8 (3–19) mg/l for home-brewed, paper-filtered coffees (n = 5). Boiled coffee had high concentrations of cafestol and kahweol, 939 mg/L and 678 mg/L, but having it poured through a fabric filter reduced the concentrations to 28 and 21 mg/L. Other coffee brews (percolator, French press) contained intermediate levels of cafestol (∼90 mg/L) and kahweol (∼70 mg/L), with the exception of some espresso samples with high levels (up to 2447 mg/L cafestol).

Per these numbers, 270 ml (9.5 Oz) boiled unfiltered coffee would raise your LDL by 102 mg/dL, enough to go from zero to too much. Espresso and its variants are comparable to boiled unfiltered coffee, in terms of diterpenes to caffeine ratio.

[edit:] there's a 100x variance in the sample ranges, probably relating to whether there is a filter.

[edit:] this is one of the most understated headlines I've seen, with a single cup having enormous health implications, and the trivial solution of passing it through a 1 cent paper filter.

[u/RAPEBERT_CUNTINGTON → u/Mechasteel]

this is one of the most understated headlines I've seen, with a single cup having enormous health implications,

What? A single cup isn't adding 500mg of LDL to your body. It literally says "daily", as in someone who drinks this every single day of their life. Also, the source they quote about 0.014mmol/L per 1mg cafestol says those figures come from a study where the cafestol was suspended in oily solutions and swallowed, not consumed as coffee: https://journals.sagepub.com/doi/epdf/10.1177/014107689608901107

The actual studies where 20+ people had on average EIGHT cups (56g of beans) of either boiled or filtered coffee per day "only" showed a 30mg/dL increase in cholesterol with the boiled coffee. Yeah it's significant and bad, but it's nowhere close to the theoretical 102mg/dL from a single cup you propose.

I really doubt how accurately they sampled everything considering the insane variation between samples, and how closely their "boiled coffee" match how it's actually made and consumed. They boiled it with grounds for 3 minutes and then steeped it. Literally everyone I know boils the water, takes it off the heat to add grounds, and just let it steep until the grounds sink. They also stored it in a freezer for up to 4 weeks before analysis. Most of the compounds in unfiltered coffee likely come from suspended bean particles. How does the freezing affect the particles and the oils in the particles?

Extrapolating that a cup has "enormous health implications" from a short study with a microscopic sample size and unconfirmed assumptions is crazy.

[u/TheYamManInAPram]

What about instant coffee?

[u/super_akwen → u/TheYamManInAPram]

I'm in a bus, so not the best place to carefully read articles, but from what I skim-read, they didn't analyze it. However, they cited this study. It's old, but apparently, instant coffee tested in that study had negligible amounts of diterpenes, at least compated to boiled coffee.

[u/metalhead82 → u/super_akwen]

Have a nice rest of your bus ride!

[u/farteagle → u/metalhead82]

Still waiting for an update on how the rest of the bus ride went.

[u/metalhead82 → u/farteagle]

Me too. Was this a cross country bus trip?

[u/chrisuu__ → u/farteagle]

I sure hope the bus driver didn't suffer a heart attack caused by drinking too much boiled coffee that raised their cholesterol to dangerous levels.

[u/wasteabuse → u/super_akwen]

Phew, I drink metal mesh filtered coffee in the morning and instant coffee at work, thought I was doing max damage.

[u/windowpuncher → u/wasteabuse]

It may really depend on the brand.

Boil down the factors, though. If you have cholesterol issues, maybe filter with paper or cloth. Or even double filter. Or cut down on the coffee (rip).

If you don't have issues, though, don't worry about it.

[u/BHPhreak → u/TheYamManInAPram]

instant is best.

also, boiling water in a kettle supposedly removes some of the micro plastics - causes them to get calcified along the glass wall of the kettle.

so instant drinkers get less cholesterol and less micro plastics. on top of being much easier and less time consuming.

[u/chrisuu__ → u/BHPhreak]

Yay, I always had the impression instant was the junk-food equivalent of coffee. But it sounds like it's more like the brown rice equivalent.

[u/ay-foo → u/BHPhreak]

I drink instant but mostly because I'm lazy and it tastes fine. You're saying there's plastic in tap water and you should boil it before mixing with instant coffee?

[u/munderbunny → u/TheYamManInAPram]

Instant coffee reportedly has less, a lot less actually, similar to paper filters. Nutritionfacts covered multiple papers related to this very topic.

[u/pianobench007 → u/TheYamManInAPram]

Instant coffee is brewed coffee that is filtered to remove the grounds. Then the liquid is now either vaporized or freeze dried into the crystal powder that is now instant coffee.

The vaporization process super heats the liquid to 1000F instantly removing the water vapor from the coffee liquid until it settles back as a crystal. Your instant coffee.

The freeze dried method similarly removes the water except it is freeze dried and then placed in a low pressure chamber. That removes the water and now you have instant coffee. Freeze dried.

Both methods filter to remove the coffee grounds. 

[u/SommeThing]

Does espresso have the same concerns?

[u/Left-Preparation6997 → u/SommeThing]

https://www.nmcd-journal.com/cms/10.1016/j.numecd.2025.103933/asset/ec1fb8b1-5d63-43d2-9881-df8c19f6e365/main.assets/ga1.jpg

yes, couldn't tell you what their espresso method was

[u/Potato1223]

In contrast, I read that tea bags, and what coffee filters also use, contains insane amounts of microplastics

[u/roamingandy → u/Potato1223]

Some do. Most decent brands don't, or are in the process of moving away from it

[u/Potato1223 → u/roamingandy]

I don’t think the majority of people use decent brands.

[u/DiceMaster → u/Potato1223]

Lipton is on the list u/roamingandy shared, and that's about as basic as it gets. Cheap, too, though you can certainly get cheaper

[u/MJOLNIRdragoon → u/DiceMaster]

Yeah: Lipton, Bigelow, Celestial, Twinings. That's like 90% of the tea someplace like Target stocks.

[u/st8odk → u/Potato1223]

and maybe dioxin if it's white?

[u/Potato1223 → u/st8odk]

Oh god, is that another chemical I should watch out for

[u/st8odk → u/Potato1223]

maybe, i've given up

[u/caspissinclair]

By "workplace" coffee machines do they mean k-cup style, because that's pretty much every one I've seen in break rooms?

[u/dftba-ftw → u/caspissinclair]

From the paper

Brewing machines produce coffee from whole or ground beans in approximately 10–30 s, as the hot water mixes with the coffee and passes a metal filter.

It isn't entirely accurate for them to say this as blanket statement, I was recently doing some research related to my own high LDL and came across the connection to unfiltered coffee - yes a lot of these machines use a metal filter, but a lot of them also use a paper filter in the form of a continuous paper roll.

[u/AbareSaruMk2 → u/dftba-ftw]

In your investigations would you say there was enough evidence point to probably cause on the coffee to high LDLs? I exercise and eat well. My vice is the Mola Pot which I drink daily. Coffee was mentioned as a possible source but I dismissed it at the time. Maybe I should throw in a paper filter as mentioned here or switch brewing method.

[u/o793523 → u/AbareSaruMk2]

My personal experience is yes, unfiltered coffee raises LDL even in an otherwise healthy individual. I get my blood tested at least annually (sometimes more) and I eat well and exercise, mountain climb, play sports, and run. Drinking several cups daily from a metal mesh filter french press raise my LDL to the 'bad' range. Now I use a Keurig with a reusable metal k cup with paper filters. Diet and exercise remained the same, and my numbers moved back into the 'good' range within a month or two.

[u/dftba-ftw → u/AbareSaruMk2]

From what I could tell from the literature, if it is unfiltered, yes it can have a significant impact on LDL even at low doses around 2-3 cups. Which can be anywhere from 8oz to 24oz depending on if the research was using 8oz to a cup or the historical 4-6oz in a "cup of coffee"

[u/TheSecretAstronaut → u/caspissinclair]

Standard k-cups (non-refillable) all have internal paper filters. This is more in reference to reusable filter solutions like mesh baskets or other refillable alternatives, as these will have similar brewed properties to other methods such as French press, Turkish coffee, etc., where the grounds are added directly to the water with no medium to truly filter through. The mesh layer serves only to separate the larger grounds from the water, but smaller dregs, oils, and other compounds found in coffee beans are not filtered out and will be present in the final brew.

[u/StupidRedditUsername → u/caspissinclair]

I would think it’s crap like this: https://www.selecta.com/se/sv/coffee-and-hot-beverages/evoca-maestro

[u/feanaro_finwion]

I wonder where cold coffee stands?

[u/lordnigz]

What about the pod machines

[u/Twiggyhiggle → u/lordnigz]

Should be fine- as most pods have a paper filter like the Kcups. If you are using a reusable with a metal mesh it will be in between higher.

[u/wardial → u/Twiggyhiggle]

What about microplastics?

[u/Twiggyhiggle → u/wardial]

What about them? I am collecting them in my balls.

[u/wardial → u/Twiggyhiggle]

do plastic Keurig pods contribute to our consumption of microplastics? sorry about your balls.

[u/doinkeroni-jones → u/wardial]

Yes of course they do

[u/throwaway3113151]

Don’t most workplaces use a filter to make drip coffee? I’m so confused.

[u/cinnamon-toast-life → u/throwaway3113151]

Yeah, all offices I have worked at just have regular Mr. coffee type machines with a paper filter and big glass carafe. One person just brews a new pot if they empty the last one. But maybe they mean those big coffee machines like they have in hospitals?

[u/Healthy-Bluebird9357]

What about espresso machines???

[u/Cynchronization → u/Healthy-Bluebird9357]

From the chart provided in another comment, espresso is just as bad or worse than boiled. And here I finally bought a superautomatic.

[u/mvea]

I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:

https://www.nmcd-journal.com/article/S0939-4753(25)00087-0/fulltext

From the linked article:

Cholesterol-elevating substances in coffee from machines at work

The coffee from most of the coffee machines in workplaces contains relatively high levels of cholesterol-elevating substances. There is a big difference in comparison to coffee made in regular paper filter coffee makers, which filter out most of these substances.

The fact that boiled coffee in a pot contains high levels of the worst of the cholesterol-elevating substances, the diterpenes cafestol and kahweol, is already known. It’s even mentioned in the latest Nordic nutritional recommendations, where the advice is to reduce or refrain from drinking boiled coffee. However, a regular drip-filter coffee maker, which uses a paper filter, manages to almost completely filter out these cholesterol-elevating substances.

How well conventional coffee machines, which are found in public environments such as workplaces, filter out these substances had not been investigated up until now. In the study, the researchers studied fourteen coffee machines in break rooms at different workplaces. The coffee used was five regular brands of ground coffee. They took samples from the coffee made by the machines on a number of separate occasions and analysed the contents. There was a big difference between the machines in terms of the levels of cafestol and kahweol in the coffee they made, but the levels could also differ at different times.

The most common type of coffee machine, in the study called a brewing machine, is the one that produced coffee with the highest concentrations of diterpenes. In comparative analyses, the researchers investigated peculator coffee, espresso, French press coffee, boiled coffee, and boiled coffee poured through a fabric filter. The boiled coffee contained the highest levels of diterpenes per cup. Some espresso samples also contained high levels, but there was great variation.

[u/BobbleBobble → u/mvea]

It's important to note that there's strong evidence that this compound (cafestol) can elevate LDL, but there's also (albeit more preliminary) evidence that it also has anti inflammatory, anti tumor, and positive blood glucose control effects. So it's not clear to say the net effect is negative (especially in people with normal range cholesterol)

[u/darkenedzone]

I looked at the original published paper, and frankly the science isn't very good. They compared office samples to lab samples, prepared in entirely different methods, didn't include confidence intervals on their data, and used a sample size of 4 for espresso machines. Not 4 machines, 4 measurements. In total, they only had 28 samples from 14 machines in 4 offices, and the majority of them were paper filtered. Even within their espresso samples, they had 1/4 at or around the same cafestol concentration as paper filter, another in the range of a brewing machine (like a Keurig), and then two that were about 10x higher. Frankly, I'm surprised this got published with the amount of confounding variables...

It sounds more like there's something with the specific machines they looked at, rather than the brewing methods themselves. I'd honestly be interested to see a further study, but this barely seems like a preliminary proof-of-concept.

[u/Koala-Available]

In this info 40 years old?

[u/Cicer → u/Koala-Available]

IDK about 40 but I’ve been reading about it for years. It pops up on Reddit every few months

[u/Jimmycrackcorn80085]

Sounds like a "big paper coffee filter" hit piece

[u/blanketswithsmallpox → u/Jimmycrackcorn80085]

Quick everyone was learning about micro plastics in all of our products. We need good non-french press!

Also publish a bunch of studies right after showing we can filter larger microplastics from bad tap water with those same filters!!!

https://pubmed.ncbi.nlm.nih.gov/36848832/ - Pouring hot water through drip bags releases thousands of microplastics into coffee Hao-Peng Wang et al. Food Chem. 2023.

https://pubs.acs.org/doi/10.1021/acs.est.1c06768# Common Single-Use Consumer Plastic Products Release Trillions of Sub-100 nm Nanoparticles per Liter into Water during Normal Use

[u/Glittery_Kittens]

So does this have any relevance to normal coffee makers? And is there a meaningful difference between paper filters and screen filters?

[u/herrakonna]

One thing to note about this and similar studies is that they are primarily looking at "heavy" coffee drinkers, who consume coffee all day long. Other studies have noted that the negative effects of the chemicals that are not removed by paper filters are not significant for those who drink only a few cups in the morning rather than continually throughout the day.

As such, I myself have no concerns about enjoying my one large mug of french press each morning.

I used to be a drink-coffee-all-day person, but realized it was messing with the quality of my sleep, so limit myself for those reasons. If I resumed drinking all day, I'd switch to paper filters.

[u/thenrix → u/herrakonna]

This study basis was 3 cups of coffee 5 days a week which is roughly 2 cups a day. Not excessive really

[u/Scabendari → u/thenrix]

And to further specify, in scientific context, a cup is typically defined as about 240ml or 8 ounces. My average sized office cup holds up to 500mL.

[u/9outof10timesWrong]

Honestly, this seems like a pretty poor quality paper. Their results have a huge range and there's no explanation. For example, they have some samples that are like 800 and 20 and then say that group has an average of 410. Well actually you have one that's producing high levels while the other is on par with paper filters.

Boiled coffee was prepared by mixing3.5tbsp.(≈21g)extracourse-ground(~1300μm)coffee beans with 3.5dLwater in a pot, bringing up to a boil and letting it boil under a lid for about 3 min.

They don't even specify the type of coffee bean? Like it's different coffee in every different machine. Does this not have a greater affect on results than the method used to prepare the coffee? Not to mention small sample sizes.

Seems like there are major flaws with this study.

[u/Ajanu11 → u/9outof10timesWrong]

It took me way too long to find this comment, I was about to ask if I was the only person who hates this paper. They just bought some coffee and found some chemicals. As you said, they didn't control for beans. The interesting thing here is how much does each method extract? But they don't know how much was there to start with. The espresso results are all over the place. That could be beans, they could have paper filters. I don't understand why they didn't at least get ground coffee samples with the coffee.

[u/Ok_Substantial_1714]

Paper filters also commonly contain PFAS, same with tea bags

[u/dodecakiwi]

Looks like it's a mixed bag really: https://pmc.ncbi.nlm.nih.gov/articles/PMC6747192/

[u/No-Extent-2029]

What is boiled coffee in a pot??