Pressed coffee is going mainstream — but should you drink it?

Heidi Godman
Heidi Godman, Executive Editor, Harvard Health Letter

The coffee aficionados in my life seem a little smug these days. They feel vindicated now that the brew they’ve long touted as superior — European pressed coffee — has finally gained mainstream acceptance. No longer the domain of trendy coffee houses and upscale restaurants, pressed coffee is now fashionable in the United States and can be found in many places where coffee is sold. And the device to make this kind of coffee — known as a French press — has begun popping up on all kinds of store shelves, from tony boutiques to big-box chains. But this hot trend has a cold hard fact you should know about.

What’s the brouhaha?

You make pressed coffee by mixing boiled water (hot or cold) and coarsely ground coffee beans in a special glass pitcher, then letting the mixture steep for a few minutes. There’s no filter to keep coffee grounds from getting into your cup; instead, you press an attached mesh plunger from the top of the pitcher to the bottom to strain the liquid and trap the coffee grounds. And it’s this lack of a filter that makes pressed coffee different and potentially risky if you drink too much of it.

Without a filter, some of the oily substances found in coffee beans, called diterpenes, wind up in your cup. Coffee aficionados say these oils make the brew taste better. But you should know that diterpenes have been shown to have a negative impact on health. “Five to eight cups a day of unfiltered coffee may actually raise your ‘bad’ LDL cholesterol,” says Dr. Eric Rimm, a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health.

The dark(er) side of that cup of joe

Even coffee that’s poured through a filter in an automatic drip coffee maker comes with some degree of risk. Coffee contains caffeine, and in some people, too much caffeine — more than 300 milligrams per day — may lead to insomnia, nervousness, heart palpitations, and the jitters. Caffeine consumed after noontime is especially likely to interfere with sleep. “If you’re drinking coffee and getting less sleep every night, you may be putting yourself at risk for developing other chronic conditions over the long term,” says Dr. Rimm. Too much caffeine may also raise blood pressure. The negative effects of caffeine go away when you stop consuming it.

The good news about coffee

Coffee is also full of compounds that are good for health, such as:

  • magnesium, potassium, and niacin
  • caffeine, which in small amounts can reduce fatigue and improve alertness and concentration
  • potent compounds such as chlorogenic acid and polyphenols, which have antioxidant properties that help prevent cell damage.

Dr. Rimm and his colleagues believe the combination of those ingredients may delay the absorption of blood sugar, help cells draw sugar from the blood, increase metabolic rate, and help blood vessels contract and relax. Those actions, they suspect, account for coffee’s association with lower blood pressure, a slower rate of weight gain with age, and reduced risks for developing type 2 diabetes or dying from cardiovascular disease or neurological diseases.

“Where we clearly see the greatest benefit is in the realm of diabetes and obesity,” says Dr. Rimm. He says the health benefits of filtered coffee are associated with an intake of one to five cups per day, and for many health conditions, it doesn’t matter much if the coffee has caffeine or not.

To press or not to press

If you choose to drink unfiltered, pressed coffee, Dr. Rimm recommends that you keep an eye on your cholesterol levels, to make sure your LDL levels don’t rise over time. And keep your pressed coffee habit in check: stick to no more than four cups per day. You should also limit your intake of filtered coffee to no more than five cups per day.

Remember, too, that some of the biggest risks of coffee come from what you may add to it: cream, sugar, or sugary syrup. These add saturated fat and empty calories to your diet, boost your blood sugar, and promote weight gain. So be careful about what you put into your cup.

And if coffee isn’t already part of your daily routine, don’t worry about starting a love affair with it. There are plenty of other ways to stay healthy and trendy without becoming a java aficionado — or even a plain old coffee drinker.

Comments:

  1. Allan

    Sorry but at 74 I find that using a plastic coffee makers seem to affect my memory. Switching to a french press was a big improvement. I always do not drink the last bit of coffee because of the grounds that find their way into the cup.

    All this leads me to ask if it really is healthy to brew coffee ( an acid) with boiling water. Is it possible that chemicals may leatch out of the plastic baskets used to hold the coffee?

  2. Jim Ratliff

    A very disappointing article, and doesn’t meet the standard I typically expect from Harvard Health. One example:
    “But you should know that diterpenes have been shown to have a negative impact on health.” And then there’s no follow up on this claim at all! No further mention of diterpenes. No detail on what the “negative impact on health” is. No citations!

  3. Paul

    Did someone mention Joe?
    CrackingJoe.uk

    Coffee is a natural product and the benefits of drinking it in moderation keep stacking up.

    80)

  4. Arthur Sudler

    I would like to see the scope of the article expanded to include cold brew coffee and the usefulness – or lack there of – of using material such as cheesecloth to filter pressed and cold brew coffee.

    Drinking cold brew coffee may benefit some people in that it may eliminate the need for a sweetener.

  5. Ray

    The coffee press I used has a mesh filter. The problem starts when the beans are grounded too fine.

  6. Jacqueline

    Those stress cost your blood presser to go up

  7. David

    I suspect that that decaffeinated coffee give an irregular heart beat. Has anyone else found this.

  8. T. E. Somerville

    “You make pressed coffee by mixing boiled water (hot or cold)….” What do you mean by boiled cold water? Water that has been first boiled and then allowed to cool? And if so, does anyone really make coffee this way–except perhaps in areas where there is reason to believe that the water supply may be contaminated?

    • Pejvak

      Adding water at 100°C burns coffee and ruins the taste. It is recommended to wait for few minutes for it to cool down to about 80°C before pouring.

  9. Vera Ericscon

    In reply to the “boiled water” issue, I remember the old fashioned “Navy method”, as we called it: into 1 cup of boiling water (in a saucepan,) drop 1 teaspoon of ground coffee, bring to a boil again. Let simmer for approx. 3 mins and BON APPETIT.”
    Don’t forget to use a sieve when pouring coffee into your cup!

  10. HS, Ph.D.

    How can I believe your “trusted advice from Harvard” when there are no responses to so many comments that challenge your article?

  11. Pete

    The cholesterol-raising effect of coffee oils has been known for a long time (de Roos and Katan. Curr Opin Lipidol 1999). To combat mildly elevated cholesterol, I switched from French press to pour over about two years ago and saw a 10 point drop in both LDL and total cholesterol that has persisted since. Make of it what you will – an uncontrolled study and sample size of one 😉

    • redplanet

      Nothing wrong with anecdotal evidence. Used to be called case studies and written in journals. And what difference does it make what happens to others – you don’t have their biological terrain or their coffee habits. What matters for each individual is what happens to them – and A/B, A/B testing on the self is fine. And when you go to the doctor he looks at your numbers, not an average from a study. Double blinds were designed for agricultural studies originally. The designers did not think them appropriate for drug studies but the drug companies loved them because the outcome was easier to control. I learned all this at Stanford, dept of stat, back in the day.

  12. Paul B

    Also, actual citations would be helpful for some of the claims in here, beyond “Dr. Rimm said…”.

  13. Paul B

    This article could benefit from some serious editing, particularly for logical consistency.
    Also, advising against drinking 5-8(!) cups of coffee a day seems like a non-starter — yes, it does seem like that would cause insomnia. But that is unrelated to whether or not the coffee is pressed, no?

  14. Nell

    Is there association with. drinking too much caffine from coffee and tea , and ringing in the ears (tinnatus)?

  15. Janice

    Can you comment on the risks and benefits of making coffee the Italian way, with a Moka pot?
    Thank you.

  16. Dr Mick Foster

    Coffee receives accolades one month and warnings
    the next month.. No wonder physicians are having
    credibility problems..

  17. Tamie

    No mention made of instant coffee – regular, not decade. I’d really appreciate information about that,
    advantages , disadvantages, same compounds that contribute to good health.

  18. spanky

    Are you saying you never use hot water in a french press?

  19. Rumpert Roamer

    Is pressed coffee the one called Expresso Coffee in Italy? Thanks., Robert R

  20. John

    It’s a cafetiere not a coffee press!

  21. Nannette Kredlow

    How about coffee made in a traditional espresso maker?

  22. Tom Somma

    Pressed Coffee? Since when is pressed coffee made with boiling water? That would make it as bad a regular coffee. I only use cold water, and refrigerate it 12-24 hours. This is what was recently reported in the latest issue of Consumers Report. Using cold water is the standard whether using just a carafe or one of the many automatic systems in that issue. Where did you ever come up with the idea of using boiled water?

    • Arthur Sudlet

      I was first introduced to it as “French Press.” In my opinion it does produce a more robust flavor than drip. I enjoy cold brew in the summer months. But whether it is drip, press, or cold brew the quality of the bean, the quality and type of roast, and individual preferences are all factors.