Does unfiltered coffee raise blood lipids? Research finds that this is actually the case...

Coffee has become an indispensable drink in the lives of many modern young people and office workers.

Coffee tastes good and can refresh you, but there is a saying that drinking unfiltered coffee can increase blood lipids. What’s going on?

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Does drinking coffee increase blood lipids?

As early as 1985, an article in the American Journal of Cardiology attempted to explore the relationship between coffee, tea, elevated cholesterol and cardiovascular disease, but no clear conclusion was reached. (1)

A few years later, a clinical study showed that unfiltered coffee would raise serum cholesterol, but this effect was reduced by 80% when it was simply filtered through coffee filters. (2) The results may be due to the fact that the filter removed the lipid components in the coffee, rather than the act of brewing the coffee.

Another cross-sectional study and trial in 2003 showed that drinking filtered coffee also increased serum cholesterol. The purpose of this controlled study was to evaluate the effects of consuming and not consuming filtered brewed coffee on blood lipids. Giving up coffee for 3 weeks can reduce serum total cholesterol by 0.22 to 0.36 mmol/l. (3)

A more recent study in 2018 revealed the relationship between drinking coffee and elevated blood cholesterol levels. The results showed that coffee that was not filtered through filter paper contained more diterpenes, cafestol, and kahweol, which can cause elevated blood cholesterol levels. However, filtering through filter paper can reduce cafestol. The porosity of the filter paper and the particle size of the ground roasted coffee are the determining factors in obtaining filtered coffee brews with lower cafestol content. (4)

In addition, the changes in blood lipids associated with coffee drinking are also related to different coffee making methods, such as espresso, brewed coffee, instant coffee, etc., as well as the age and gender of the drinker. (5)

Can I still drink coffee?

Of course you can drink it. In the above studies, the volunteers consumed large amounts of coffee every day, even more than 6 cups. This is basically equivalent to drinking coffee like water, which is not recommended in the first place.

Everything has multiple sides, and we need to understand the world dialectically. Water is an essential element for maintaining life, but drinking too much water can lead to water poisoning, so drinking in moderation is important.

There is also a lot of research on the benefits of drinking coffee.

For example, this 2017 meta-analysis study collected research from multiple different fields and summarized the various effects of coffee on health, including cardiovascular disease, cancer, diabetes, cognitive function, etc. The study believes that, except for pregnant women and women with osteoporosis who were not included in the study, the health benefits of moderate coffee drinking generally outweigh the health risks. (6)

What does moderate drinking mean?

The internationally recognized recommended daily intake of caffeine for healthy adults is less than 400 mg. This is not easy to grasp. According to some previous reports, a cup of milk tea from some brands actually exceeds this recommended amount. Generally, we recommend 1-2 cups of American or espresso. This actually meets the coffee needs of most of us.

Ordinary people don't need to think so much about drinking 1-2 cups of coffee a day, but if you drink coffee as water every day, you should pay attention and it is recommended to reduce the amount appropriately. In addition, for some special groups such as pregnant women, breastfeeding women, heart patients, etc., coffee intake should be avoided or reduced.

1. Klatsky, AL, Petitti, DB, Armstrong, MA, & Friedman, GD (1985). Coffee, tea, and cholestrol. The American Journal of Cardiology, 55, 577–578.2. AHOLA, I., JAUHIAINEN, M., ARO, A. 230 (4), pp. 293-297.doi: 10.1111/j.1365-2796.1991.tb00447.x

3. Strandhagen, E., Thelle, DS Filtered coffee raises serum cholesterol: Results from a controlled study. (2003) European Journal of Clinical Nutrition, 57 (9), pp. 1164-1168. doi: 10.1038/sj.ejcn.1601668

4. Rendón MY, dos Santos Scholz MB, Bragagnolo N. Physical characteristics of the paper filter and low cafestol content filter coffee brews. Food Research International. 2018;108:280-5.

5. Svatun, Å. L., Løchen, M.-L., Thelle, DS, & Wilsgaard, T. (2022). Association between espresso coffee and serum total cholesterol: the Tromsø Study 2015–2016. Open Heart, 9(1), e001946–. https://doi.org/10.1136/openhrt-2021-001946

6. Poole, R., Kennedy, OJ, Roderick, P., Fallowfield, JA, Hayes, PC, & Parkes, J. (2017). Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ (Clinical research ed.), 359, j5024.

Author: Yuzi Sangkepu Author

Reviewer: Zhang Na, associate researcher and doctoral supervisor at the School of Public Health, Peking University