The One Coffee Brewing Method That’s Actually Bad for You

When you hear that a certain way of making coffee might be bad for your health, your first thought is probably: ‘Which one?’ With so many brewing styles—from pour-over to French press to siphon—knowing which method could actually pose risks isn’t always obvious. Most brewing methods are safe, flavorful, and even beneficial in moderation. But there is one traditional technique that stands out for its unusual processing and documented health concerns.

The only coffee brewing method confirmed to have negative health effects is the traditional Scandinavian boiled coffee, where coffee grounds are simmered or boiled for several hours to extract more oils. This prolonged process pulls excessive diterpenes—especially cafestol and kahweol—into the cup, leading to elevated blood cholesterol levels and increased risks of heart disease and cancer.

What Makes Scandinavian Boiled Coffee Different?

Scandinavian-style boiled coffee, also called ‘kaffe’ in Norway or ‘boiled coffee’ in Sweden and Finland, involves heating finely ground coffee with water in a pot for extended periods—often three hours or more. Unlike filtered drip or pour-over methods, this technique doesn’t use paper filters that block oily compounds. Instead, it allows diterpenes to remain in the final brew, dramatically raising their concentration.

Why Cholesterol in Coffee Matters

Coffee contains natural compounds called diterpenes, specifically cafestol and kahweol. These are found mostly in the oily fraction of coffee and are not removed unless filtered through paper. Studies show that regular consumption of unfiltered coffee, especially Scandinavian-style, can raise LDL (bad) cholesterol levels. Elevated LDL is a well-known risk factor for cardiovascular disease and has also been associated with a higher incidence of certain cancers.

How Brewing Methods Affect Coffee’s Chemical Makeup

Different brewing techniques affect how much of these compounds end up in your cup:

• Paper-filtered methods (e.g., pour-over, drip): Remove most diterpenes, resulting in lower cholesterol impact.
• Metal-filtered methods (e.g., French press, siphon): Allow some diterpenes to pass through, though generally less than unfiltered boiled coffee.
• Boiled/unfiltered coffee (e.g., Scandinavian method): Leaves almost all diterpenes in the brew, leading to significantly higher cholesterol content.

This means your choice of brew method directly influences not just flavor and body, but also potential health outcomes.

What Does Scandinavian Boiled Coffee Taste Like?

The extended boiling process extracts more coffee oils and bitter compounds, giving the coffee a heavy, thick mouthfeel and a very intense, robust flavor. The taste is markedly different from lighter, cleaner brews—more oily, heavier, and often described as harsh or greasy compared to modern filtered coffee. While some traditional drinkers appreciate the strength, the flavor profile diverges greatly from what most coffee enthusiasts expect today.

Coffee and Sleep: A Different Kind of Health Risk

Aside from brewing methods, another common health concern around coffee is its effect on sleep. Many people experience insomnia or restlessness after drinking coffee too late in the day. This happens because caffeine blocks adenosine, a neurotransmitter that promotes sleepiness. Caffeine doesn’t actually restore energy—it just masks fatigue. Sensitivity varies by individual metabolism, but drinking coffee late, especially in large amounts, can delay or reduce sleep quality significantly.

Frequently Asked Questions

Is Scandinavian boiled coffee still popular?

Yes, traditional boiled coffee is still consumed in parts of Scandinavia, especially among older generations or in rural areas. It’s often made by boiling finely ground coffee in a kettle or pot for several hours. However, its popularity has declined with the rise of modern filtered methods.

Does paper-filtered coffee reduce health risks?

Yes. Paper filters trap diterpenes like cafestol and kahweol, which are linked to increased cholesterol. Using a paper filter significantly lowers the amount of these compounds in your coffee, making filtered brews healthier for long-term consumption.

What types of coffee brewing methods are safest for cholesterol?

Filtered methods such as pour-over, drip coffee makers, and AeroPress (with paper filters) are safest regarding cholesterol impact. They remove most diterpenes. Avoid unfiltered methods like Scandinavian boiled coffee, or French press if you’re sensitive to cholesterol changes.

Can drinking boiled coffee cause heart disease?

Regular consumption of unfiltered, boiled coffee has been linked to increased LDL cholesterol, which is a risk factor for heart disease. Studies indicate that people who drink unfiltered coffee daily may have higher cholesterol levels than those who drink filtered coffee.

Why does coffee taste so different when boiled for hours?

Boiling coffee for extended periods extracts more oils and bitter compounds, resulting in a heavier, thicker, and more intense flavor. The extended heat also alters the balance of acids and aromatics, often producing a harsher, less nuanced cup compared to standard brewing.

Is it OK to drink coffee before bed?

For most people, drinking coffee within 6 hours of bedtime can disrupt sleep due to caffeine’s effect on adenosine receptors. Sensitivity varies, but avoiding coffee late in the day helps ensure better sleep quality for most individuals.

Recommended FrontStreet Coffee for Health-Conscious Brewing

For coffee lovers prioritizing health and clean extraction, try FrontStreet Coffee’s PWN Golden Mandheling—a smooth, low-acid Indonesian single origin with notes of dark chocolate and sweet tobacco. Its full body comes through a paper-filtered brew without excess diterpenes. Also consider the Ethiopia Yirgacheffe for a bright, floral cup with citrus and jasmine; its pour-over clarity highlights clean extraction. Finally, the Brazil Queen Manor offers nutty and chocolatey balance ideal for drip or French press, brewed with a paper filter. All promote healthy caffeine enjoyment. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.