French Impressed or Depressed? French Pressed Coffee and the Curious Case of Cafestol


While I have long enjoyed the end result of steeping a satchel of tea in a cup of boiling hot water, it never occurred to me that coffee could be brewed the same way. Ever since I was a wee tot, I associated coffee brewing with noisy appliances and wet, dirty filters filled with used grounds. Needless to say, on Christmas day 2011, my mind was officially blown.

It was on this day that I received a Bodum "Chambord" French Press coffee maker. "Duh-doy!" I said to myself as I witnessed the utter simplicity of brewing a "pressed" cup of coffee.  As the exquisite smoothness passed beyond my lips I achieved a state of caffeinated bliss that carried me beyond this earthly realm.

Recovering from my French-pressed fugue, I began to wonder "Why?"  Why was French-pressed coffee's taste so undeniable superiority? It couldn't be attributed solely to it's dashing good looks and obvious "cool" factor. There had to be more to the story than meets the eye.  To the internet I went, and within moments, Google produced much information.

My first query directed me to CoffeeGeek.com where I learned that French-pressed coffee requires freshly ground coffee beans rendered into "uniform large particles".  Such a grind is made possible by using "real" grinders like the "conical burr" models produced by Bodum. Apparently, the common blade grinder is "fake", and should be sneered at like an uncultured foreign tourist.  I also learned that while "vac pot" coffee makers first hit the scene in the 1840's, presses like my own Chambord didn't appear until the early part of the 20th century.  

Next, I navigated to an "Ask the Expert" post on Harvard University's School of Public Health website.  There I learned that, even in people who drank up to six cups of coffee per day, there was "no relationship between coffee consumption and increased risk of death from any cause, death from cancer, or death from cardiovascular disease."  This made me feel quite good about rekindling my love affair with coffee, that is, of course, until I came upon this little tidbit:

"Coffee contains a substance called cafestol that is a potent stimulator of LDL cholesterol levels. Cafestol is found in the oily fraction of coffee, and when you brew coffee with a paper filter, the cafestol gets left behind in the filter. Other methods of coffee preparation, such as the boiled coffee common in Scandinavian countries, French press coffee, or Turkish coffee, are much higher in cafestol."

It seemed that this "cafestol" was the compound that gave my French-pressed coffee its delicious body and smooth taste, yet it also seemed to produce a reliably large increase in the low density lipoproteins often associated with heart disease.  On to Wikipedia.com I went, where "cafestol" was entered into the search field.

From Wikipedia.com:

"Cafestol is a diterpene molecule present in coffee.

A typical bean of Coffea arabica contains about 0.6% cafestol by weight. Cafestol is present in highest quantity in unfiltered coffee drinks such as French press coffee or Turkish coffee/Greek coffee. In filtered coffee drinks such as drip brewed coffee, it is present in only negligible amounts.

Studies have shown that regular consumption of boiled coffee increases serum cholesterol by 8% in men and 10% in women. For those drinking filter coffee, the effect was only significant for women."

Again with the regular consuming and the serum cholesterol raising!  My only recourse was to plumb the references for more information that might vindicate my desire to consume regular cups of blessedly unctuous French-pressed coffee (with oh so pleasant notes of dark chocolate and chicory!)

The first paper was titled, "Cafestol and Kahweol, Review of Toxicological Literature" and it's worth a read if you like scientific papers and organic chemistry.  But here are a few key snippets from the executive summary.

First, the researchers give a little background on cafestol and a related compound called kahweol:

"Global coffee production comes from mainly two species, Coffea arabica and Coffea robusta. Cafestol and kahweol, which are naturally occurring diterpenes found only in coffee, are present in the unsaponifiable lipid fraction. Their content in a coffee drink is influenced by the brew method; brewing releases oil droplets containing cafestol and kahweol from the ground coffee beans. Boiled coffee, such as Scandinavian-style and Turkish-style, contains the highest concentrations, while instant, drip-filtered, and percolated coffee brews contain negligible amounts."

They also verified the cholesterol-raising effect noted in the Harvard article:

"Studies have shown that an intake of cafestol and kahweol causes an increase in total cholesterol as well as low density lipoprotein (LDL) cholesterol, triglycerides, and alanine aminotransferase (ALT) activity."

But, it seems like cafestol and kahweol may also show potential benefits (at least in animal models):

"Cafestol and kahweol have shown anticarcinogenic properties. Feeding green coffee beans to female Sprague-Dawley rats prior to or subsequent to 7,12-dimethylbenz[a]anthracene  (DMBA) administration inhibited the formation of mammary tumors. Instant coffee yielded the same results as the green coffee."

The mechanism for this effect is hypothesized to be related to increased glutathione S-transferase (GST) activity:

"In mice and rats, both substances were found to induce GST activity of the liver and intestinal mucosa. Studies with derivatives of cafestol and kahweol indicate that the furan moiety is the active site for induction of the enzyme activity."

The research paper concluded with a report on "no known toxic effects" have been related to cafestol or kahweol consumption, so it seems that the consensus veiwpoint is that while it may raise cholesterol levels, it reduces risk of cancer.

Continued internet exploration yielded some more information that seems to tip the scales in favor of cafestol consumption by way of French-pressed coffee.  It was a New Scientist article titled "Parkinson's protection without caffeine or nicotine" and it summarized research conducted by the University of Washington (however, being that this was in Seattle, there may have been some pressure from a certain multinational coffee conglomerate...cough, cough, Starbucks, cough).  Following up on a previous study that linked coffee and cigarette consumption with a decreased risk of Parkinson's disease, the researchers proposed the following hypothesis:

"Normally, dopamine-producing neurons in the mutant flies die off as they age. But a diet featuring coffee and tobacco kept the neurons alive in all the flies tested at 20 days old, whether or not their food contained caffeine or nicotine...

His team went on to identify a compound found in both decaf and normal coffee called cafestol that seems partially responsible for its neuro-protective effects. Cafestol activates a protein produced by flies called Nrf2, and the team found that blocking Nrf2 diminished coffee's protective effect on dopamine neurons."

So, as I sit here, sipping my delightful cup of cafestol laced coffee, I can take heart in the knowledge that although my LDL is likely on the rise, the future looks bright and lively for my dopamine neurons and glutathione S-transferase activity.

To get brewing, simply pick up a French Press (they're pretty cheap, ~$15 bucks) and some coffee and follow the steps below.

Start with a clean French Press.

Add ground coffee (remember "uniform large particles") according to how much coffee you would like to brew.

Add hot water and stir.  Let the coffee steep for 2 to 3 minutes.

Affix the lid to the pot, ensuring that the spout isn't "open". 

Slowly "press" the plunger down, if it gets stuck, simply back it up to clear the filter before continuing to press.

I have some killer recipes for taking your French pressed coffee to the next level, so stay tuned for updates!
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About Tony Fed

Tony is the host of the Paleo Magazine Radio podcast, author of "Paleo Grilling: A Modern Caveman's Guide to Cooking with Fire", and Cofounder of Powerful PT, an innovative information resource for Fitness Professionals. He has appeared on numerous local and national television and radio broadcasts and regularly hosts healthy cooking workshops and informational lectures. He is also a full-time Personal Trainer and Wellness Consultant who lives in Jacksonville Florida with his wife Jamie.
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6 comments:

  1. I am wondering, what form of LDL was increasing? There are two types, pattern A and pattern B. Pattern B LDL increases your risk for heart disease due to it's ability to get under the cells in your arteries and causing plaque build up. Pattern A is larger, more buoyant and won't cause the plaque build up. Also, consumption of carbohydrates, especially fructose (which can come from a variety of sources) can increase the amount of pattern B LDL

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  2. Ran out of filters this morning and had to broke out my French press, so much better, perhaps not as good as cold brew, but close!

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  3. Really informative post! I love my french press.
    ...plus, Bodum just makes really delightful products.

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  4. While the authors of the study did not indicate whether the LDL increase was in the "large fluffy" or "small dense" variety, they did indicate that there was an effect on serum levels of alanine aminotranferase, an enzyme linked to liver activity. However, this may be a transitory effect...

    "In a study using unfiltered brewed coffee (cafetière) versus filtered coffee, Urgert et al. (1996b) found elevated levels of total cholesterol (specifically, LDL cholesterol), ALT activity, and triglycerides in individuals who had consumed 0.9 L cafetière coffee (38 mg [0.12 mmol] cafestol, 33 mg [0.10 mmol] kahweol) per day for 24 weeks; the filtered coffee provided <1 mg of the diterpenes. ALT activity was increased 80% above baseline values relative to filtered coffee. All increases, however, were reversible upon withdrawal of treatment.

    The elevation of ALT suggests the liver is the target organ of cafestol and kahweol(Weuston-Van der Wouw et al., 1994; Urgert et al., 1996c). However, a study of the chronic intake of coffee (consumption of 5 or more cups of boiled or filtered coffee per day and persons aged 40-42 years) found no increased ALT activity (Urgert et al., 1996c).

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  5. oh that's great info i never would have guessed thanks

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  6. Your blog is full of entertainment and helpful information that can allure to anyone anytime. Continue posting!
    Dean T. Emrich

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