Natural Oils In Coffee, Good Or Bad?

Been reading some highly conflicting data. Some suggesting that the oils are what carry the actual health benefits of coffee, including the chlorogenic acid and is what makes it a healthy beverage if brewed fresh and from quality beans.


Others are suggesting that these oils are actually BAD for you, and to always use a paper filter method of brewing as these oils carry the terpenes which are bad for you, and terrible for your gut flora and also your choloesterol.


Anyone want to save me some digging deep in to more research on this??


I have always been using a french press as I have previously WANTED the oils. In addition to this i prefer a dirty cup (love the oils and sediment and rinds) vs a clean cup and hate paper filters due to taste. But if the oils are doing more harm than good, would be inclined to switch over. Gotta love the internet and conflicting data... If anyone knows would be interested to hear.




  • It's a hard to say. The very same oils that are said to be bad for your cholesterol because they raise LDL are said to be good for your liver. I just got an aeropress and the inventor of it is pro getting rid of the oils. The aeropress uses a small paper filter, but it can also be used with a metal filter. Regardless, its the best tasting coffee I've ever made so I'll go without the oils.

  • Andy BoskampAndy Boskamp Andy Boskamp
    edited April 2014

    metal filter for aeropress (in case you change your mind about those oils :wink: )


    “The impediment to action advances action. What stands in the way becomes the way.”


    - Marcus Aurelius

  • Yeah... it really does suck. More research I read points to French Pressed coffee allowing the problem to persist...



    Many coffee aficionados eschew the filtered brew, arguing that filters remove some of a bean’s savory flavor. What filtering really does — besides screening out gritty grounds — is eliminate coffee’s oils, rich in alcohols known as diterpenes. Two of these alcohols, cafestol and kahweol, can elicit a number of unhealthy changes in the blood of regular coffee drinkers.

    The newest diterpene effect to be identified — an increase in blood levels of an enzyme that is normally associated with damage to liver cells — emerged in a 6-month long Dutch trial with healthy, coffee-loving volunteers.

    Rob Urgert and his colleagues at Wageningen Agricultural University in the Netherlands recruited 46 men and women to participate in the experiment. All of the volunteers received a locally popular blend of coffee and strict instructions on how to brew two batches of it each day.

    Urgert’s group directed half the men and women to pour boiling water through 33 grams of ground beans sitting in a cone-shaped filter until the dripping brew filled a half-liter jar.

    The remaining volunteers were told to pour their boiling water and ground beans together into a French press — also known as cafetière — coffee maker. The top of this type of pot is fitted with a large plunger. The volunteers were told to stir the mix and then to let the grounds steep for 2 to 5 minutes before they pushed the plunger down. (This effectively stops the brewing and traps any floating grounds so that they won’t enter the cup.) The coffee was then decanted into another bottle.

    The participants, all healthy and between the ages 19 and 69, were told to drink almost a liter of the coffee daily for 24 weeks. Every 2 to 4 weeks, the scientists brought the volunteers in for blood tests that measured concentrations of cholesterol, triglycerides, and a host of liver enzymes.

    A report of the study, published in today’s British Medical Journal, shows that men and women who drank the filtered coffee exhibited no changes over the course of the trial in any of the assayed blood constituents. Previous studies by Urgert’s group had shown that such a filter effectively removes all of the coffee-oil’s diterpenes. Those who drank coffee made by the French press method, however, displayed a host of undesirable changes.

    For instance, levels of one liver enzyme (alanine aminotransferase) nearly doubled early in the trial. This enzyme serves as a marker of potential stress to the liver, Urgert explains. “If there is some change in liver cell integrity, the concentration of these enzymes in the blood can rise.”

    Fortunately, he notes, the enzyme rise among cafetière coffee drinkers was far less than that in persons with liver disease. Moreover, his data indicate, the rise in these enzymes is transient. Levels were already falling by the end of 24 weeks and continued to fall further during the 12 weeks after the trial ended.

    However, Urgert told Science News Online, the enzyme findings remain interesting because “until now there have been very few foods identified as having such an effect on liver cells.”

    The Dutch nutrition scientists also observed a sharp, transitory 26 percent rise in serum triglyceride levels among the men and women drinking French-pressed coffee. Like the liver-enzyme changes, however, the triglycerides fell as the study progressed. By the end of 24 weeks, their concentrations had already returned to levels recorded before the start of the study.

    Of far greater concern, Urgert believes, were increases of between 9 and 14 percent in the concentrations of low-density-lipoprotein (LDL) cholesterol — the so-called bad cholesterol — in volunteers drinking the pressed brew. An increase this large in LDLs, a risk factor for heart disease, might over a lifetime elevate an individual’s chance of developing coronary disease by up to 20 percent, he notes. Also observed in several shorter studies by this group, this potent elevation in LDL concentrations shows no sign of attenuating with time.

    “These [diterpenes] are amazingly predictable,” Urgert observes. “If you knew much you gave to Dutch volunteers, you could almost exactly predict their change in LDL cholesterol.”

    This link to persistent LDL increases “should also apply to Turkish coffee, which contains similar amounts of cafestol and kahweol per cup,” the researchers point out. Significant LDL increases might also accompany heavy consumption of Italian espresso, they add. However, owing to the small size of espresso cups, one would have to drink some 25 cups per day.

    The good news: Grandma’s old metal percolator basket will filter out the diterpenes almost as effectively as do the new generation of filtering drip coffee makers.

    What if you mix your coffee up from instants? No problem. Analyses of 19 different instant coffees marketed in Europe, the United States, and North Africa — including 6 decaffeinated brands — turned up only “minimal” quantities of the diterpenes in the brewed drinks.

    That doesn’t mean that some forms of coffee are completely innocuous. A study conducted in California, a few years back, showed that drinking at least two cups a day throughout life can increase the risk that an individual will suffer from osteoporosis in old age.

    Tea drinkers, by contrast, can take heart in their habit. [The Younger Daughter will love this. - LG] The diterpenes that caused LDL and other changes in the new study are not found in other hot beverages. Most regular (not herbal) teas also are rich in a class of compounds known as flavonoids. These can largely halt oxidative changes in the blood — changes that can transform dietary fats into artery-clogging plaque.


    Barrett-Connor, E., J.C. Chang, and S.L. Edelstein. 1994. Coffee-associated osteoporosis offset by daily milk consumption. Journal of the American Medical Association 271(Jan. 26):280.

    Urgert, R., et al. 1996. Comparison of effect of cafetière and filtered coffee on serum concentrations of liver aminotransferases and lipids: Six month randomized controlled trial. British Medical Journal 313(Nov. 30):8.

    Urgert, R., et al. 1995. Levels of the cholesterol-elevating diterpenes cafestol and kahweol in various coffee brews. Journal of Agricultural and Food Chemistry 43(August):2167.

  • One thing is for certain... I have to say that filtered coffee SUCKS the big one!! I don't know how you guys do it. It takes away the best flavor in coffee. I have been french pressin' for a year straight now. Nothing beats the taste and flavours in a dirty cup in my opinion.


    So now, I am contemplating giving up deliciousness for health, and also at the expense of having crappy tasting coffee. Sadly, I might be joining the masses drinking drip or filtered coffee now :(. Really really not happy about this. I know its just a change in method. But I love my coffee in the french press. But I think one can find enough evidence that the oils may be doing more harm than good.

  • ACH85ACH85 ✭✭
    edited April 2014

    I would not base your coffee consumption habits on the Urgert studies.


    Cafestol and kahweol are the very oils Dave mentions as being beneficial. A quick look at Wikipedia, a very basic resource, shows cafestol is anticarcinogenic in rats and neuroprotective in a fruit fly model of Parkinson's disease. Kahweol is beneficial for bone, anti-inflammatory and anti-angiogenic which may inhibit cancer cell growth. Both are beneficial in the treatment of mesothelioma. Drinking of unfiltered coffee is associated with decreased risk of cancer in large epidemiological studies. 


    Urgert had his subjects drinking A LITER of coffee a day. Further, he did not even bother to control for their diets, and with only 24 members in the experimental group, that could have a big impact. 


    The smoking gun in the full text of his 1996 study is that the french press experimental group complained of the strong flavor, and in fact he started out with a much larger group and many dropped out, leaving him with 24 members. Urgert did not even bother to control what was added to the coffee... 


    And what do most people add to their coffee when they find the bitter flavor to be too strong? MILK AND SUGAR, KNOWN TO ELEVATE LDL. 



Sign In or Register to comment.