Unfiltered Coffee & Cholesterol: How French Press and Espresso Affect Your Heart Health

 Here’s what happened. A while ago, while I was scrolling through short-form videos, I came across a piece of medical-related news about coffee. It said that drinking coffee made without a filtration step—such as coffee brewed with a moka pot or a French press—may raise cholesterol levels in the body, thereby increasing the risk of cardiovascular and cerebrovascular diseases.

I don’t claim any authority when it comes to medical science, but this still made me curious enough to dig a little deeper and see what was really going on. So today, I’d like to talk about this topic with you.

The reason behind this has to do with two natural oils found in coffee: cafestol and kahweol. Cafestol is a diterpene compound extracted from coffee beans and is structurally similar to kahweol. Research suggests that cafestol may increase cholesterol levels. Kahweol, also a natural diterpene compound from coffee beans, has been shown to have anti-inflammatory, anti-angiogenic, and anti-cancer properties.

Both of these compounds are fat-soluble, meaning they can enter the coffee liquid during brewing. Unfiltered coffee—such as French press coffee, moka pot coffee, and espresso, all of which are commonly brewed without paper filters—tends to contain higher concentrations of cafestol and kahweol. With immersion brewing methods like the French press, hot water remains in contact with the coffee grounds for a longer period of time, and without paper filtration, these oily compounds are able to pass freely into the cup.

In contrast, paper-filtered coffee, such as pour-over coffee, contains almost none of these substances. That’s because paper filters effectively trap and absorb these oils, preventing them from passing through into the final brew.

So once we understand how these compounds exist in coffee and how they relate to different brewing methods, the next question is: how exactly do they raise cholesterol levels in the body?

One key reason is that they interfere with receptors in the liver that are responsible for regulating cholesterol levels. This reduces the liver’s ability to remove low-density lipoprotein (LDL) cholesterol—often referred to as “bad cholesterol”—from the bloodstream. At the same time, these compounds may stimulate the liver to produce more cholesterol on its own, while also reducing the excretion of bile acids (which are made from cholesterol). As a result, more cholesterol is reabsorbed back into the bloodstream.

Ultimately, this leads to higher levels of total cholesterol and LDL cholesterol. Some studies suggest that long-term, heavy consumption of unfiltered coffee can raise LDL cholesterol levels by approximately 3%–10%, depending on the amount consumed and the type of coffee.

Medical research indicates that for healthy individuals, drinking one to two cups of espresso or milk-based espresso drinks per day has a relatively limited impact. However, the cumulative effect of long-term, heavy consumption of French press coffee should not be overlooked—especially for people who already have high cholesterol or cardiovascular risk. In these cases, the cholesterol-raising effect of cafestol can be quite significant.

Therefore, if you are particularly concerned about your cholesterol levels, it’s best to choose paper-filtered coffee as your daily option. Brewing methods such as French press, Turkish coffee, and boiled coffee tend to contain the highest levels of these coffee oils.

For healthy individuals with normal cholesterol levels, no cardiovascular disease risk, and moderate coffee consumption, the impact is usually minimal. There’s no need to completely give up your favorite type of coffee—the key lies in moderation and taking your personal health condition into account. For those who have already been diagnosed with hypercholesterolemia or have cardiovascular risk factors, in addition to controlling saturated and trans fat intake, switching from unfiltered coffee to filtered coffee can be a simple and effective supportive measure.

By this logic, it seems we’ve gained yet another reason to accept why American-style coffee filters out those oils. Well, I guess I really can’t stay away from this topic lately. No need to panic—just drink responsibly and within your limits. Wishing everyone many happy coffee moments ☕️

Unfiltered Coffee Can Raise Cholesterol | The Most Dangerous Brewing Method Explained

 One cup wakes you up. Two cups keep you going. The bitter, aromatic taste is hard to resist. Among all the things that stimulate the brain and create mild dependence, coffee is arguably one of the healthiest. A morning cup, an afternoon cup, one more before work begins—this is everyday life for countless coffee lovers.

But what many people don’t realize is that choosing the wrong coffee—or brewing it the wrong way—can quietly work against your health. Certain types of coffee can actually raise total cholesterol and LDL cholesterol levels. The hidden culprit?
Unfiltered coffee.

Let’s start with a quick explanation of LDL cholesterol, often referred to as “bad cholesterol.” Unlike HDL (“good cholesterol”), which helps clear cholesterol from blood vessels, LDL transports cholesterol from the liver throughout the body. When LDL levels are too high, it can penetrate blood vessel walls, become oxidized, trigger inflammation, and gradually form plaques. These plaques narrow arteries and increase the risk of cardiovascular disease—earning LDL its reputation as a silent killer.

This helps explain a puzzling situation many people face: they eat low-fat, low-salt diets, exercise regularly, even limit eggs—yet their LDL cholesterol still comes back elevated on blood tests. Stranger still, some people see their levels return to normal months later. The reason?
They stopped drinking coffee.

The idea that “drinking coffee the wrong way can raise blood lipids” isn’t just internet rumor—it’s backed by solid scientific evidence. Studies show that brewing method makes a dramatic difference, and the key factor affecting cholesterol is whether the coffee is filtered.

Unfiltered coffee refers to coffee brewed without paper filters. This includes espresso from home or office machines, French press coffee, moka pot coffee, Turkish coffee, boiled coffee, and similar methods.

A meta-analysis of 14 randomized controlled trials found that compared with paper-filtered coffee, long-term consumption of about 900 ml of unfiltered coffee per day increased LDL cholesterol by an average of 17.8 mg/dL, translating into an estimated 11% increase in cardiovascular disease risk. These findings have been repeatedly confirmed by umbrella reviews in The BMJ and studies supported by the NIH. For people who already have high cholesterol, the effect is even more pronounced.

So where does the problem actually come from?
Not the milk in milk-based drinks—but coffee oils, which many people assume are beneficial.

Coffee bean oils contain two compounds that act behind the scenes: cafestol and kahweol. These diterpenes make up about 1% of coffee bean content. They are easily extracted by hot water, but they do not pass through paper filters. As a result, boiled or unfiltered coffee contains especially high concentrations.

These two compounds interfere with the body’s cholesterol regulation system by blocking the excretion pathways of bile acids and neutral sterols. When cholesterol that should be eliminated stays trapped in the body, LDL levels gradually rise.

The amount of these diterpenes varies dramatically by brewing method:

Unfiltered methods (moka pot, French press)

Office coffee machines / chain café coffee
Paper-filtered coffee (pour-over, drip coffee, filter bags)

Most office espresso machines use metal filters, which trap only part of the oils. In other words, they “filter—but not very well.” A Swedish study revealed that coffee from office machines contained 15–18 times more diterpenes than home-brewed paper-filtered coffee. Some espresso samples had cafestol levels as high as 2,447 mg/L. In contrast, boiled coffee filtered through paper saw these compounds drop from 939 mg/L to just 28 mg/L—a 97% reduction.

No need to panic—coffee lovers don’t have to give up their daily lifeline. Just remember two principles: moderation and the right brewing method.

Most of the documented risk comes from long-term consumption of 900 ml or more of unfiltered coffee per day. One regular cup a day is generally not a problem.

More importantly, choose safer brewing methods. Cold brew and paper-filtered coffee are the simplest and most affordable ways to reduce risk. They remove nearly all cafestol and kahweol, preventing LDL cholesterol from rising.

To wrap up, here are some practical tips:

• At home, choose pour-over or drip machines with paper filters

• At chain cafés, opt for cold brew—or ask if the coffee is paper-filtered

• In the office, consider pooling resources for pour-over gear, or stock filter coffee bags and paper filters

• If you really enjoy espresso or French press coffee, keep portions in check—no more than 900 ml per day (roughly two large cups)

Drink smart, and let coffee work with your health—not against it.

☕ What Is Coffee Crema? The Science Behind Espresso’s Golden Layer

 

When you drink an espresso, what are you actually drinking?
Before your lips even touch the cup, your eyes and nose experience the magic first — that rich aroma rising from a deep brown liquid, topped with a layer of golden caramel-colored foam. This shimmering reddish-brown layer is what we call coffee crema — or simply Crema in Italian.

For many coffee lovers, crema is one of the key indicators of a well-made espresso.

“Look at that thick, velvety crema — this shot must be great.”
“Wow, it even has tiger stripes — gotta take a photo!”
But what exactly is this much-admired crema?

In Italian, crema refers to the fine foam that forms when coffee’s natural water-soluble oils and carbon dioxide combine briefly during extraction. It’s made up mostly of tiny bubbles, mixed with small amounts of fat, protein, and other compounds.

When water passes through the coffee puck under high temperature and pressure, it extracts soluble materials while emulsifying the coffee’s natural fats and oils. Meanwhile, the carbon dioxide trapped in the coffee grounds becomes supersaturated — unable to escape due to the pressure — and forms countless microbubbles that rise to the surface. The result is that creamy layer of foam we know as crema.

Because pressure is crucial in this process, you’ll typically need an espresso machine to produce a shot with good crema. Some moka pots or manual espresso makers can create a similar effect, but if the temperature and pressure aren’t high enough, the flavor and texture will fall short.

A perfect espresso is a balance of all its elements — bright on the palate, rich in body, and smooth as it finishes down the throat.

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What Does Crema Actually Do?

Crema is one of the most iconic features of espresso, and it serves several purposes:

1. Enhancing texture
A rich crema adds a silky mouthfeel to espresso. However, too much can make the coffee taste bitter, astringent, or overly oily.

2. Preserving aroma
Freshly extracted crema sits on top of the espresso like a lid, slowing the loss of aromatic compounds. But it fades quickly, which is why espresso should be enjoyed immediately.

3. Protecting latte art
A moderate amount of crema improves fluidity, helping create cleaner lines and longer-lasting patterns in latte art.

As for those “tiger stripes” — they appear when fine coffee particles slip through during extraction, leaving small dark spots on the crema’s surface. They don’t affect flavor much, but they sure make for great photos.

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What Affects the Formation of Crema?

Beyond pressure and temperature, factors like bean freshness, grind size, and roast level also influence crema quality.

Roasting is the ultimate catalyst of coffee flavor. During roasting, beans lose moisture, darken, and undergo complex chemical transformations that produce their signature aroma. The darker the roast, the more carbon dioxide is released — which, when emulsified with fats during extraction, creates a fuller crema on top.

However, as roasted beans age, they gradually lose both CO₂ and oils. Over time, the gases inside the beans escape and interact with oxygen, causing crema production to decline.

Grind size and the coffee-to-water ratio are also critical.
If the grind is too coarse, extraction efficiency drops, meaning fewer emulsified fats and weaker crema. Similarly, if the brew ratio is too high (too much water for the coffee amount), you’ll get thinner crema as well.

Ultimately, the amount of carbon dioxide and fat compounds inside the coffee beans themselves determines whether your espresso will crown itself with that beautiful, golden crema.