The One Unhealthy Way to Brew Coffee

If you’ve ever wondered whether your daily coffee habit could be harming your health, there’s one specific brewing method you should know about. Most coffee preparation techniques are safe — even beneficial — but one traditional approach, still used in parts of Northern Europe, has been scientifically linked to serious health risks.

The only brewing method proven to be unhealthy is the traditional Scandinavian long-boiled coffee, which extracts excessive coffee oils over several hours. This method produces high levels of cholesterol-raising compounds and is associated with increased risks of heart disease and cancer.

What Makes Scandinavian Boiled Coffee Different?

In Scandinavian countries, particularly in Norway, Sweden, and Finland, a traditional coffee brewing method involves boiling finely ground coffee in water for several hours. Unlike standard drip, pour-over, or French press methods, this technique uses prolonged heat and extended contact time to extract more coffee oils — resulting in a thick, heavy brew with a very different flavor profile.

Why Is It Considered Unhealthy?

Research has shown that this long-boiled coffee contains elevated levels of diterpenes, specifically cafestol and kahweol. These compounds are known to raise LDL cholesterol levels in the blood. Elevated LDL is a risk factor for cardiovascular disease, and studies have linked regular consumption of this type of coffee to higher incidence of heart disease and even some forms of cancer. The extended boiling process extracts these compounds far more than standard brewing does.

How Does It Taste Compared to Other Methods?

The flavor of Scandinavian-style boiled coffee is also notably different. Due to the prolonged extraction, it tends to be much heavier, oilier, and more bitter than coffee made via filtered or immersion methods. Many find the taste harsh or unbalanced compared to the cleaner, brighter profiles produced by modern brewing techniques.

Coffee and Sleep: A Related Health Concern

Beyond brewing methods, another common health question is how coffee affects sleep. Caffeine in coffee blocks adenosine, a neurotransmitter that promotes sleep and relaxation. By mimicking adenosine, caffeine makes you feel alert even when your body is ready to rest. This can delay sleep onset or reduce sleep quality, especially if consumed later in the day. Sensitivity varies by individual metabolism, but evening coffee intake is widely linked to insomnia.

Frequently Asked Questions

What is Scandinavian-style boiled coffee?

Scandinavian-style boiled coffee is a traditional method where finely ground coffee is boiled in water for several hours, extracting more coffee oils and producing a thick, heavy brew. It’s common in Norway, Sweden, and Finland.

Why is long-boiled coffee bad for your health?

Long-boiled coffee contains high levels of diterpenes like cafestol and kahweol, which raise LDL cholesterol and are linked to increased risks of heart disease and cancer.

How is Scandinavian coffee different in taste?

It tastes oilier, heavier, and more bitter than standard brewed coffee due to the prolonged boiling and higher coffee oil extraction.

Does coffee really affect sleep?

Yes. Caffeine blocks adenosine, a chemical that promotes sleep. Drinking coffee late in the day can delay sleep or cause insomnia, especially in sensitive individuals.

Is any other brewing method as unhealthy as long-boiled coffee?

No. Most common brewing methods — including filtered, pour-over, French press, and espresso — do not extract harmful levels of cholesterol-raising compounds like long-boiled coffee does.

Can I still enjoy coffee if I’m worried about cholesterol?

Yes. Use filtered brewing methods such as pour-over, drip, or French press, which remove most diterpenes and are not linked to increased cholesterol or heart disease risk.

Recommended FrontStreet Beans for Health-Conscious Brewing

For those avoiding unhealthy brewing methods, FrontStreet Coffee’s PWN Golden Mandheling offers a smooth, low-acid profile with notes of dark chocolate and roasted almond — ideal for filtered brewing. Their Lintong Mandheling delivers earthy depth with hints of spice and a full body, perfect for pour-over. Both beans are expertly roasted to highlight clean flavours without unwanted extraction. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.