Use of coffee filters in brewing may lower LDL and risk for heart disease

ByScott Buzby

Fact checked byRichard Smith

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Key takeaways:

Coffee filters may help lower LDL by removing compounds shown to raise cholesterol.
Workplace brewing machines without filters produced coffee with higher diterpene concentrations vs. other methods with filters.

Coffee filters reduce intake of LDL cholesterol-generating compounds found in the brew and subsequently may lower risk for atherosclerotic heart disease, researchers reported.

Workplace brewing machines produced coffee with diterpene concentrations several times higher compared with coffee made using paper or fiber filters, according to new data published in Nutrition, Metabolism and Cardiovascular Diseases.

Graphical depiction of data presented in article — Data were derived from Orrje E, et al. *Nutr Metab Cardiovasc Dis*. 2025:doi:10.1016/j.numecd.2025.103933.

“The Nordic nutrition recommendations from 2023 recommend that unfiltered coffee (eg, boiled) should be limited because it contains cafestol and kahweol which increase cholesterol levels. In Sweden, machine coffee is regularly consumed at work but until now, such coffee has not been tested in this aspect,” David Iggman, MD, PhD, docent and researcher in the department of public health and caring sciences at Uppsala University in Falun, Sweden, told Healio. “Based on what we know today, coffee intake seems overall beneficial for atherosclerotic heart disease, but the brewing method may be of importance. Since filtered and instant coffee contain very low amounts of these cholesterol-raising substances, such coffee seems like the safer choice for regular consumers.”

Coffee and LDL cholesterol

In a 1994 study published in the Journal of Lipid Research, researchers identified two diterpene compounds in coffee beans, cafestol and kahweol, which were shown to increase LDL cholesterol.

David Iggman

Citing a prior study published in the Annual Review of Nutrition, Iggman and colleagues stated LDL increases 0.0104 mmol/L (approximately 0.187 mg/dL) per milligram daily cafestol intake, and 0.0016 mmol/L (approximately 0.029 mg/dL) per milligram daily kahweol intake.

In the 2018 multi-society Guideline on the Management of Blood Cholesterol published in Circulation and the Journal of the American College of Cardiology, the writing committee stated the optimal LDL level to minimize CV risk was below 2.6 mmol/L (100 mg/dL).

To better understand the actual concentration of diterpenes in coffee, Iggman and colleagues tested samples from varying coffee machines and brew styles at four hospital workplaces in Sweden and compared them with several styles of “home brewing.”

Workplace coffee makers included brewing machines, which brew via hot water mixed with the coffee passing through a metal filter, and liquid models, which do not use a filter and mix liquid coffee concentrate with hot water. Instant coffee machines, which mix instant coffee with hot water, were not included in the analysis.

The comparison home-brewed coffees were made using Scandinavian-style drip, percolator, French press and boiled coffee-making methods, all using medium to dark roast Arabica coffees with medium grind size.

Lowering ASCVD risk with coffee filters

Overall, boiled coffee contained the highest median concentrations of cafestol (939.2 mg/L) and kahweol (677.9 mg/L), which were considerably reduced after it was poured through a fabric filter (mean cafestol, 28 mg/L; mean kahweol, 21.2 mg/L).

The next highest concentrations were found in workplace brewing machines, with median cafestol levels of 175.7 mg/L and kahweol levels of 141.8 mg/L, according to the study.

The researchers estimated that replacing three cups per day of brewing machine coffee with paper-filtered coffee would reduce LDL cholesterol by 0.58 mmol/L and subsequently lower relative ASCVD risk up to 13% over 5 years or 36% over 40 years.

Diterpene levels were also high in espresso, but measurements varied widely from machine to machine, according to the study.

“We were not surprised by the main results that brewing machine coffee contains moderate diterpene concentrations,” Iggman told Healio. “However, the large variation within — over time — and between these machines was somewhat surprising and something we can’t explain. Also the substantial variation between different espresso samples was surprising and something that needs further study.”

French press and percolator coffees contained intermediate diterpene levels, ranging from 86.8 mg/L to 91.2 mg/L for cafestol and 68.7 mg/L to 69.2 mg/L for kahweol.

The lowest diterpene concentrations were reported in liquid-model machines and paper-filtered drip-brew coffees, including those normal or perforated “aroma” filters.

“We do not know exactly how much machine coffee affects blood lipids, since this has not yet been tested in human subjects,” Iggman told Healio. “Completely unfiltered coffee such as Scandinavian-style boiled coffee has been tested in several controlled studies and we know it has a substantial effect on LDL cholesterol — at least 10% — but it also contains higher diterpene concentrations than machine coffee. Also, more long-term observational studies on clinical outcomes are warranted. So far, only one Norwegian study has compared reported intake of boiled and paper-filtered coffee, with lower cholesterol and CV mortality in individuals consuming paper-filtered coffee.”