Voltage Coffee Testing Series — French Press & Health

Is French Press Bad For You? The Surprising Facts.

Newspapers love to kick around the question of whether drinking coffee is good for you or not. It’s something that hits close to home, because coffee is not some supplement sitting in the back of the cabinet. It is the thing many of us reach for before we are fully verbal in the morning.

Everybody loves a good debate to go with a good cup of joe.

Back in 2016, an article from Harvard Health made the rounds suggesting that pressed coffee — including French press coffee — might not be the harmless little morning ritual we all wanted it to be.^[1] That got people talking, and for good reason. French press coffee has a reputation for being richer, fuller, and more “real coffee” than standard drip. Unfortunately, the same thing that gives it that heavier body is also what puts it in the middle of the cholesterol conversation.

So let’s dig in carefully. Not panic.

Not throw your French press out the window.

Just look at what the research actually says and what it means for people who drink coffee out of normal mugs instead of tiny laboratory fairy cups.

So, Is French Press Coffee Bad For You?

That matters because French press coffee uses a metal mesh filter. But so do other brewing methods. If you drink coffee made without a paper filter, more of those oils can make it into your cup. In high enough amounts, cafestol in particular can raise LDL cholesterol — the “bad” cholesterol your doctor is usually talking about when they give you that look over the top of the lab report.^{[2] [4]}

This does not mean one cup of French press is going to wreck your heart. It does mean that if your cholesterol is already high, if high cholesterol runs in your family, or if your “one cup” is actually a giant mug with a refill waiting behind it, you may want to take it easy on the French press.

Here’s a quick idea of what this could all mean for you:

Why French Press Coffee is Different

Let’s start at the beginning. Unless you’re drinking Turkish coffee, you don’t want any grounds in your coffee. They taste bad and feel worse.

There are many ways of keeping the grounds out of your coffee. The simplest is letting the grounds settle and pouring very carefully, which is a bold strategy usually followed by regret. Most brewing methods use some kind of filter instead.

Paper filters are standard for automatic drip, pour-over, and Chemex-style brewing. French press, Moka pot, espresso, percolator, and reusable metal drip filters rely on metal screens or pressure rather than a paper barrier. In either case, the filter keeps the grounds out. The difference is the rest of the stuff that gets through.

Paper filters catch more of coffee’s oily compounds. Metal filters let more of them pass into the finished drink.^[2] That is part of why French press coffee tastes richer and heavier.

So why does French press get the spotlight when it is not the only metal-filtered or unfiltered method?

Mostly because it is familiar, easy to buy, and usually brewed in real mug-sized portions. Harvard Health called pressed coffee a method that had “gained mainstream acceptance,” and once a brewing method becomes a common kitchen upgrade instead of a niche coffee-nerd ritual, it becomes the one newspapers, health blogs, and worried coffee drinkers latch onto.^[1] Moka pots, Turkish coffee, percolators, and metal drip filters belong in the same broader conversation, but French press is the one many people actually picture on the counter.

That is why French press gets dragged into health articles while plain paper-filtered drip coffee usually gets a pass.

The Real Issue: Cafestol, Kahweol, And Cholesterol

Coffee contains hundreds of compounds. Some are probably part of the reason coffee has been associated with health benefits in observational studies. Others are more complicated. Cafestol and kahweol fall into the complicated bucket.

Cafestol and kahweol are diterpenes, naturally occurring compounds found in coffee oils. Paper filters remove much more of them than metal filters do, which is why filtered coffee and unfiltered coffee can have different effects on cholesterol.^{[2] [5]}

The research on this point has been fairly consistent for a long time. A six-month randomized trial comparing cafetière coffee — basically French press-style coffee — with filtered coffee found that five to six strong cups a day raised LDL cholesterol by 9–14% relative to filtered coffee.^[2] Another study found that drinking 0.9 liters per day of French press coffee increased activity in lipid-transfer proteins, which may help explain how cafestol and kahweol push LDL cholesterol upward.^[3]

That sounds dramatic, but it needs context.

French press coffee has not been shown to be uniquely dangerous in some mystical French-press-only way. The issue is broader: unfiltered or insufficiently filtered coffee contains more cholesterol-raising diterpenes. That includes French press, Scandinavian boiled coffee, Turkish/Greek coffee, some percolator coffee, metal-filter drip coffee, and potentially some machine coffees depending on how they are brewed and filtered.^{[5] [6]}

Espresso is also part of this conversation, but there is an important difference. Espresso can be high in cafestol concentration, but the serving size is small. Most of us drink big mugs of French press and tiny cups of espresso. That difference matters.

The concentration of cafestol is about the same, but the small serving size makes the amount you drink fairly small.

How Much French Press Coffee Is Too Much?

This is where the answer gets annoying, which usually means it is getting closer to real life.

Harvard Health quoted Dr. Eric Rimm of the Harvard T.H. Chan School of Public Health as saying that five to eight cups a day of unfiltered coffee may raise LDL cholesterol.^[1] The same article recommends that people who drink pressed coffee keep an eye on cholesterol levels and keep pressed coffee to no more than four cups per day.^[1]

The BMJ cafetière trial used five to six strong cups per day, totaling 0.9 liters, for 24 weeks.^[2] That is a lot of coffee, but it is not an impossible amount of coffee. If you own a 750 mL French press and drink most of it yourself, you are not living in some imaginary “nobody actually drinks that much” zone. You are right in the neighborhood where these studies start to feel a little silly.

These aren’t big numbers — the optimal range for LDL cholesterol is 100–129 mg/dL — but they’re not nothing.

For many people, the practical risk line is probably not one small cup. It is the daily habit: large servings, repeated over months or years, especially in someone whose LDL is already moving the wrong direction.

A Quick Note About “Cups,” Mugs, And Serving Size

This is important enough to put near the top, because “cup” is one of those words that sounds precise until real humans start using it.

In the key cafetière/French press-style trial, five to six strong cups meant 0.9 liters per day.^[2] That works out to roughly 150–180 mL per study cup, or about 5–6 U.S. fluid ounces. That is smaller than an 8-ounce measuring cup and much smaller than the 12–16 ounce mug many of us actually drink from.

The FDA’s caffeine guidance is a good example of how confusing this gets. When talking about caffeine, the FDA says 400 mg per day is not generally associated with negative effects for most adults, and describes that as about two to three 12-fluid-ounce cups of coffee.^[7]

This is a caffeine conversation, not French press or a cafestol conversation, but it shows why “cups per day” needs translation.

What Newer Research Adds

The basic French press cholesterol story is not new, but newer research helps sharpen the advice.

A 2024 review in Nutrients concluded that moderate coffee consumption is not generally detrimental to cardiovascular health and may even be associated with reduced cardiovascular risk in observational studies.^[8]

The same review also points out the big problem with sweeping coffee claims: a “cup of coffee” is not well defined. A cup can vary in size, caffeine, coffee oils, brewing method, roast, additives, and overall nutritional impact.^[8]

In other words, “coffee is healthy” and “unfiltered coffee can raise LDL” can both be true at the same time.

A 2024 paper on coffee diterpenes described cafestol as one of the most potent cholesterol-elevating compounds in the human diet and noted that unfiltered brews such as French press, boiled coffee, and Turkish coffee contain higher levels of these compounds than paper-filtered coffee.^[4]

Fast-forward, a 2025 study added another interesting wrinkle: some workplace coffee machines may produce coffee with more cafestol and kahweol than paper-filtered home coffee, though generally less than boiled coffee. French press and percolator coffee landed in an intermediate range in that analysis.^[6] So once again, the lesson is not “French press alone is bad.”

The lesson is that filtering method matters.

What Can You Do If You Love French Press Coffee.

If you already have high LDL cholesterol, cutting back on French press coffee may be worth considering. That doesn’t necessarily mean you have to stop drinking coffee. It may mean switching brewing methods to something paper-filtered like drip, pour-over, or Chemex.

If you want to take smaller adjustments, start by looking at volume.

How big is your mug?

How much of the French press do you drink yourself?

Are you drinking French press daily, or just on slower weekend mornings when you can pretend life is under control?

One other factor that may matter is roast. Some research suggests diterpene levels can vary by roast and preparation, and darker roasts may contain less cafestol than lighter roasts, though brewing method remains the bigger lever here.^[4]

Can You Use a Paper Filter With French Press Coffee?

Yes, adding a paper-filter step should reduce some of the cafestol and kahweol that normally pass through a French press metal filter. That is the whole reason paper-filtered coffee behaves differently in the cholesterol research.^{[2] [8]}

There are a few ways people do it.

Some place a paper filter with the plunger screen, though that can create resistance and should be pressed slowly.

Others brew normally in the French press and then pour the finished coffee through a paper filter into a mug or carafe.

This can work, but it’s slow, messy, and annoying enough to make you question your commitment to both health and coffee.

If your LDL is high and you still want French press flavor, the paper-filter workaround is worth trying. If you hate it, alternating brew methods may be easier to stick with than forcing yourself into a daily ritual you hate.

Is French Press Coffee Still Worth Drinking?

I started researching this question years ago assuming the answer would be a simple no-problem-at-all. I wanted to say French press coffee was fine unless you were drinking it by the gallon. Then the serving-size math and the cholesterol data made that answer harder to defend.

My answer now is still not panic. It is more like: French press coffee is a little bad for your cholesterol if you drink a lot of it, and how much that matters depends on your body.

If your cholesterol is great, your intake is moderate, and French press is one of life’s small pleasures, I would not tell you to throw it away. Coffee in general has plenty of evidence pointing in a favorable direction when consumed moderately and without turning it into dessert.^{[7] [8]}

But if your LDL is high, if your family history is ugly, or if your morning “cup” is actually a 16-ounce mug with backup, I would take the French press question seriously. Rotate in paper-filtered coffee. Try a pour-over or AeroPress to change things up. Consider using a paper filter with your French press. Most importantly, bring it up the next time you review your cholesterol numbers.

In simple terms: if high cholesterol runs in your family, you might want to ease up on that French press.

That is not the answer French press lovers want. It is not even the answer I wanted. But it is probably the most honest one: French press coffee is delicious, not uniquely evil, and not completely innocent.