May 10 2018

Do Coffee Brewing Methods Matter For Health?

By Mark Sisson

inline coffee brewingCoffee is a perpetual topic of interest, and for good reason: Almost everyone drinks it, almost everyone is passionate about it, and it’s pretty darn good for you. A recent post covered whether coffee breaks a fast or not. Before that, I told you how to make your coffee healthier. And on a regular basis, I cover something coffee-related in the weekly Dear Mark. One aspect of coffee I’ve never explored, however, is how coffee preparation and processing affects its health effects.

What’s healthier—filtered or unfiltered? Dark roast or light roast? Pre-ground or whole bean? French press or drip? Let’s get to it.

Filtered vs Unfiltered

Filtered coffee is coffee that runs through a paper filter, which catches most of the oils. Unfiltered coffee is coffee that doesn’t go through a paper filter; either it’s completely unfiltered (grounds directly in water) or it runs through a metal filter, which allows the oils to pass through. Unfiltered coffee is often referred to in the scientific literature as “boiled coffee.”

Filtered coffee includes drip, pour-over (unless you use a permanent filter that allows passage of the oils), and any method in which the coffee passes through a paper filter.

Unfiltered/boiled coffee brewing methods include French press, Moka pot/percolator, Aeropress, espresso.

Cold brew coffee can be either filtered or unfiltered, depending on what kind of filter you use to strain the final product.

Conventional wisdom is scared of those oils because they contain two lipid compounds  called cafestol (great name for a coffee shop) and kahweol, high doses of which elevate cholesterol and suppress LDL clearance from animal models. That does sound bad; suppressed LDL clearance means LDL particles hang around longer in the blood to be oxidized and form atherosclerotic lesions. Do the animal mdoels transfer over to humans?

Maybe not. While 73 mg of purified cafestol a day for six weeks can increase cholesterol by a worrisome 66 mg/dL, the average cup of French press coffee contains between 3-6 mg; 73 mg isn’t a normal physiological dose. In one study, boiled coffee consumption was associated with a more modest 8% cholesterol increase in men and a 10% increase in women. That’s cholesterol, not LDL. Total. Besides, high fitness levels abolished the link in men, and boiled coffee was also linked to lower triglycerides in both sexes.

Or maybe. Another study found a modest association between high intakes of boiled coffee and non-fatal heart attacks. Then again, a similar (but smaller) association also existed with filtered coffee. Tough to say.

Cafestol and kahweol have beneficial effects, too. For instance, cafestol kills leukemia cells and kidney cancer cells. In mice, cafestol exerts anti-diabetic effects. Kahweol inhibits fat accumulation by activating AMPK (the same pathway triggered by fasting, exercise, and ketosis). Both compounds have anti-angiogenic effects.

Both boiled and filtered coffee reduce the risk of type 2 diabetes, but only boiled coffee confers a lower risk of prostate cancerLiver enzyme levels drop when you consume boiled coffee, and when you inject rats with a known liver toxin, boiled coffee protects them against the expected rise in liver enzymes. Most evidence suggests that coffee, whether boiled or filtered, is protective against liver cancer, liver disease, and mortality from chronic liver disease.

If you want the unfiltered coffee with the most cafestol and kahwehol, brew a light roast using a French press or the boiling method. If you want the unfiltered coffee with the least cafestol and kahwehol, brew a dark roast using a Moka pot or use the Turkish method. If you want the least of all, use a paper filter.

If you’re a heavy consumer of unfiltered coffee and you worry about the cholesterol issue, get it tested. Go for a full lipid panel, one that includes LDL particle number.

Light vs Dark Roast

Coffee beans start out green and fairly uninteresting. It’s the roasting that brings out the flavors. The darker the roast, the longer it spends in the roaster.

Light roast advantages include less oil oxidation. The lighter the roast and the fresher the coffee, the lower the oil oxidation. Keeping it in whole bean form also increases the resistance, while grinding it prematurely will oxidize the oil and mar the taste.

Light roasts tend to have more caffeine, as the roasting process degrades caffeine. But caffeine content also depends on the bean; some have more than others.

Both are good, health-wise. Some studies suggest that dark roast has a better effect than light roast on antioxidant capacity in those who drink it. Light roasts tend to be higher in chlorogenic acids, which have been shown to improve subjective mood and ability to focus—even when the coffee is decaf. Medium roasts also have antioxidant effects.

They’re all good. Coffee just works.

Whole Bean or Pre-Ground?

Depends. I like whole bean, because keeping it intact until you’re ready to brew increases the oxidative resistance (more surface area means more oxidation), retains the aroma and flavor, and—this is seemingly minor but still important to me—I like the sound of grinding beans. The sound is a huge part of the ritual of coffee preparation. It’s the same reason instant coffee just isn’t the same as whole bean coffee. It’s almost too easy.

Healthwise, I imagine pre-ground beans are fine. Despite a huge number of people buying and drinking pre-ground coffee, coffee is consistently associated with health benefits in observational studies. If you believe the observational studies are pointing toward causality, ground coffee is good for you. And if you have the opposite relationship to grinding beans, and having whole coffee beans makes it less likely that you’ll drink coffee, go with the ground. It’s fine.

Water Quality

The quality of the water matters. Mineral content is the primary concern. A 2014 study sought to determine the optimal “hardness” for coffee water and found that the specific minerals causing the hardness made a big difference.

You don’t want too much bicarbonate. Bicarbonate is bad for coffee flavor.

Sodium was also bad for coffee flavor.

You want some magnesium. Magnesium is good for coffee flavor because it enhances the dissolution of coffee flavor from beans into the water. Since coffee flavor comes from the coffee compounds, and the coffee compounds are responsible for many of the beneficial health effects, better coffee is also probably healthier coffee.

I find adding a few dashes of Trace Minerals to my coffee brewing water helps the flavor.

My Favorite Way To Make Coffee

When you include coffee:water ratios, water quality, brew method, filter choice, ground size, and all the other variables, there are millions of ways to make coffee. I won’t get into all of them. I’m actually not a big coffee snob, although I do know a good cup when I taste it. I’ll just give my basic method.

  • French press, usually with a dark roast (although I’ll sometimes do medium, dark or light if I’m feeling wild). I’m really liking Caveman Coffee’s Blacklisted.
  • Grind size is a bit finer than most people recommend for French pressing. I use a blade grinder, which would get me excommunicated from most coffee geek circles, so my grind is probably less uniform than those using a burr grinder. Eh, tastes good to me.
  • 1:12 coffee:water ratio.
  • Spring or filtered water, sometimes with a dash of Trace Minerals. Boil it, then turn off the heat and wait ten seconds.
  • Add it to the grounds, stir until it froths, cover, and press after 4 minutes.

Sometimes I make cold brew coffee concentrate:

  • 12 ounces of light roast, something fancy and floral and fruity and acidic from a local 3rd wave coffee shop.
  • Grind medium-fine.
  • Mix with 60 ounces of cold spring water with a dash of Trace Minerals in a large glass jar.
  • Stir to combine, then let sit for at least 12 hours at room temperature. I’ve also experimented with letting it brew in the sun. That works quicker, but I prefer the taste of room temperature brewed cold brew.
  • Run it through a French press, store in glass bottle in the fridge. Drink it straight up, like little cold espresso shots, or with a dash of heavy cream.

That’s it for today, folks. I think I’ll go make another cup.

How do you make coffee? Tell me all about it down below.


TAGS:  coffee

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44 thoughts on “Do Coffee Brewing Methods Matter For Health?”

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    1. If you are concerned about high caffeine, use 100% arabica beans

  1. I’ve used all kinds of coffee and every method known to man for brewing it. Unfortunately, my body didn’t like any of it. I hated giving it up but had no choice. I switched to tea years ago and felt better immediately since tea seldom causes GI issues. Most tea is considerably lower in caffeine, making it more suitable to drink late in the day. All types of tea are healthful, green tea in particular. It would be nice to see an article on the many health benefits of tea for those of us who either dislike or can’t tolerate coffee.

    1. Me too! I love the stuff, but it doesn’t love me. I agree that an article on various kinds of tea would be great.

  2. Mostly doing cold brew. If hot, french press with freshly grinded beans with a mortar. The importance of the ritual. I could not use a machine.

  3. My drink of choice is espresso but when out, I cook Turkish Coffee. Speaking of espresso and methods of brewing, you forgot to mention the makineta. Also, one should always aim for the highest quality 100% arabica beans rather than robusta.

    1. Almost always drink espresso/ristretto with nothing added to it, except in the morning, when I usually have an espresso with lots of milk.

  4. Hi, I use Aeropress and have for couple of years. Easy, convenient, I bring carry pouch with me, and great tasting, the way I brew it. I used to grind but I get locally roasted coffee and doesn’t last long. Drink my coffee Black only, except for cold brew and love cream and little sugar. I make cold brew and can’t beat it. I love to cook and making coffee is very individual and I like my coffee and not many others. Nothing worse than weak watery tasting coffee. Coffee first thing in the morning watching the news.

  5. Aeropress kits are sold with paper filters. As per the Aeropress FAQ:
    Cafestol and kahweol are diterpene molecules found in coffee. They are powerful agents that cause our bodies to increase the low density lipoproteins (LDL or “bad” cholesterol) in our blood. Cafestol and kahweol are removed from coffee by paper filters. Any coffee maker using a paper filter (such as the AeroPress coffee maker) removes virtually all of the cafestol and kahweol from the brew. We had this verified by an independent test lab for AeroPress brewed coffee.

    If you buy an aftermarket metal filter for your Aeropress, then of course the resulting brew falls under the “boiled coffee” category.

  6. Coffee is a big part of my life, and I honestly think my morning coffee ritual contributes to my health and well being. Not just because the coffee itself is good for me, but because I love the whole routine of preparing it, taking that first hot sip, and then snuggling with my dog on the sofa while I drink it and have a little quiet time. I definitely go for a dark roast, but my brewing method varies. My favorite is the French press. I also have a drip coffee maker which is nice if you want to make a larger quantity. And I’ll admit to having a Keurig for the sake of convenience.

  7. I use a Chemex with light roasts like Intelligentsia Black Cat Espresso or something akin to that. I used to drink really dark roasts for a long time, but the way some of the new wave of roasters like Intelligentsia or Ruby out of Wisconsin are approaching the roasting process makes really full bodied light roasts. Very chocolatey without the bitter overroasted taste. I did notice one small error in the filtered/unfiltered categories above. You listed Aeropress in the unfiltered category, but it uses a paper filter in the cap.

  8. I use a Cona pot–a glass-only vacuum pot that doesn’t require a filter. When I got it (twenty years ago!) my theory was that my coffee would taste better if it didn’t touch paper. I don’t know whether that’s true or not, but it does make really hot, really clear coffee. It’s old fashioned and sort of a pain to use, but I love it!

    1. I use loose tea versus teabags because it tastes better. I can always taste the paper if I use teabags.

      1. +1 for loose leaf. Tea bags are the instant coffee of the tea world. Well, maybe not that bad but they have a detrimental effect on the whole process. I can’t taste the bag but the difference in flavor due to the leaf size is stark. Most tea bags contain a very fine grind to allow quick extraction.

  9. Here in the UK we call it a Cafetiere (French Press). My coffee grinders always kept breaking so I just use the mill attachment for my blender to grind the beans, which are organic from Costco.

  10. Great read! I’m curious to know your thoughts on California’s plan to require a cancer warning on coffee. I’m not worried about it, but you likely know more than me.

    1. California often seems to be on the cutting edge of what usually doesn’t amount to a hill of beans–literally, in this case.

      1. Oh, it’ll happen. And soon everything will have a warning on it, which means nothing will have a warning on it. Humans filter out the noise. But it’ll keep a lot of “health authorities” in well-paid jobs.

  11. Hey Mark,
    You didn’t discuss the (actual/physical) coffee makers in relation to health. There’s a fellow on YT whose mother has Alzheimer’s and he (an engineer) began studying the coffee he made for her each day. The aluminum piping IN the maker, over time, puts more and more aluminum into the coffee… He tested a whole bunch of coffee makers (his, his mom’s, some neighbors’ and some he bought). They all put a LARGE amount of aluminum in the coffee! So he studied up some more, bought a bunch of makers (and tested the few he found in his ‘local population’) that are made with stainless steel piping — and they (obviously) did NOT put alum. into the coffee.

    He (shows and) lists the coffee makers that use SS piping; I bought the Krups Moka Pot, which makes really good coffee (steams the water; so it’s half-way to espresso?)

    Ah, here he is (and he does NOT sell coffee makers or coffee; he does sell his book about making what he calls “silicad”? That’s sodium silicate water that he says selectively binds and pulls the aluminum out of the body. He also provides some detailed answers in the comments.

    Haven’t ordered his book yet. Don’t know if I will — but replacing my old Cuisinart with its aluminum piping was as easy to decide on as replacing my aluminum cooking pots was!

  12. I use a pour-over cone with an unbleached filter, or a French Press, depending on my mood. I’m the only coffee drinker in my home, so I use a blade grinder. My current coffee of choice is Specialty Java’s Organic New York, New York. They roast it when you order it, so the taste is quite good. I love coffee with a splash of heavy cream. I can’t drink it after 2pm unless I want to be up very late.

  13. What about instant? I usually drink Mt Hagen Organic Fair Trade instant. Pretty good taste, low acid, and no mess.

  14. Pour over mostly. Sometimes French press. Always medium roast.

  15. Woohoo! Can’t make coffee tomorrow morning cause my mind will still be spinning about the possibilities and can’t work cause my mind won’t be spinning yet.

    Such are the great possibilities in our lives!

  16. A friend of mine swore by adding egg shells to the grounds when using a french press. I never understood how that affected the results, but this makes me think magnesium may play a role!

  17. Great article! Found a great coffee you might enjoy. Black Rifle Coffee Company … veteran owned and operated. Enjoying the BeyondBlack at this time! Love my morning coffee with coconut oil/MCT powder. Cheers!

  18. The more we know the better we can make choices, but to each their own tastes for sure! I was never a coffee guy (ok I left 15 years of high carb energy drink abuse, thank God I was addict to the only organic one around) but nearly a year ago I discovered espresso and all of its variables, barely tapping into it after several months! The only thing I know for sure (and it’s very personal) is that if it has no crema it’s barely interesting to me. One funny point is that crema is the result of proteins and fat (oils) merged by the high temperature and pressure process… proteins and fats just sounds sooo Primal to me, naturally!

  19. Coffee always smells far better than it ever tastes. The aroma in 101, the actual flavor 3 or 4…

  20. I use a French Press with Bullettproof coffee beans. Added butter and coconut oil blended with the coffee has been the morning ritual for the past 4 years, and the only thing I have before lunch. Dave Asprey from Bulletproof warns about Mycotoxins forming during the processing of coffee beans, and being the source of the ‘jitters’ as opposed to the caffeine content. Anyone have any thoughts on this?

  21. I have tried and owned half a dozen devices for brewing coffee and my preference is the French Press. I generally drink medium roasts at around the 17:1 golden ratio or light roasts with a lower water:coffee ratio.

  22. so….I am guessing that since I did not see Keurig K pod mentioned, is because they are not a good option? I’m usually rushed

  23. I only use instant coffee. Good quality stuff, I’m picky about how it tastes. But instant is significantly cheaper than ground or whole bean coffee, and all I have is a plastic coffee maker which I’d prefer not to heat repeatedly to make my coffee (though I do really really enjoy the taste over instant). I’m sticking with my instant until I can regularly afford the other stuff and maybe get a French press.

  24. As a couple of other readers have mentioned, what about instant coffee?
    I’m serious – coffee snobbery aside – are any of the benefits mentioned above present for a good quality instant coffee?

    1. What is good quality instant coffee? Starbucks Via is the only one I am aware of

  25. Light roasts are supposed to have more caffeine, some of which is destroyed by roasting/heat.
    One concern I have with the drip coffee that I drink (practically unlimited within reason from a drop-in center so I’ll go in and fill up a 1.5L old wine bottle or something) is that it’s made through a plastic filter-holder and then I think there’s more plastic on the lids of the coffee pots, then it gets poured into big plastic dispensing jugs – coffee kegs, and on that note, typing coffee kegs reminds me that I have two things to say about Starbucks at the moment:
    1. I’m probably not the first person to think of this but Starbucks is a good name for the place because I feel like you need to be some sort of superstar not to think everything is overpriced there.
    2. Since everything is overpriced, I think it should be treated like a bar. Make a pot of coffee at home and do some pre-drinking first.
    I don’t really find their coffee anything special compared to the average cup elsewhere. I wouldn’t pay for anything there but my dad got me a cup there at least once and I used some gift cards for some since it was free. I tried to sell the remaining gift card at discount price outside a few times, telling people that I would go in with them first and get it scanned in front of them so they’d know they weren’t getting scammed, but no one would go for it. Why not? It was like $12.63 and I was asking for $10 at the most. Someone could have got like, a free sip of coffee out of that. I ended up giving it to a friend as a down payment on a used bike. He’s always selling them to me.
    P.S. one more:
    3. A lot of Starbucks customers are apparently snobs.

  26. Well, reading over what I just wrote, I think that drop-in center coffee makers even heat the water in plastic in the first place, like a lot of common coffee makers. I think there’s a good chance most of the coffee I’ve had in my life has been made through plastic coffee makers.
    Sometimes I buy the cheapest instant coffee I can find (usually Walmart’s) so I can carry it around and make as concentrated coffee as I want whenever I want. It can be good mixed with other drinks and food sometimes too. For example, I like instant coffee mixed into milk.

  27. Anybody have a recommendation on the type or brand of trace minerals to use?

  28. My body doesn’t seem to like coffee. I love the smell of freshly grind beans, but the smell and taste of the drink for me is like a “burnt rubber”. Few days after drinking coffee I have acne-like spots on my skin. Tea works way better for me.

  29. Coffee becomes an important part of our daily routine. It is a perceptual topic of interest and for a good reason. Thanks for sharing the healthier and other sides of coffee. It is the really helpful post.

  30. Why do you list the aeropress as “boiled/unfiltered”? The Aeropress has a paper filter! So, does that mean that it’s better than a french press or not?