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HomeNutritionCoffee brewing method linked to increased total cholesterol levels – Norwegian study

Coffee brewing method linked to increased total cholesterol levels – Norwegian study

Espresso coffee consumption has been associated with higher total cholesterol levels, particularly in men, a population-based, cross-sectional Norwegian study found. They also found a significant relationship between filtered coffee consumption and total cholesterol, but only among women.

Numerous studies over the past few years have punted the health benefits of coffee, linking it, for instance, with a lower risk of endometrial cancer, a reduced risk of cognitive disease, and lower stroke and dementia/Alzheimer’s risk. Researchers have also suggested that up to three cups a day can lower the chances of fatal heart disease and all-cause mortality.

However, in this latest study, when distinguishing between the different brewing methods and types of coffee, the study team found that elevations in serum total cholesterol level were significantly linked to espresso consumption, especially in males, and that boiled/plunger coffee was associated with significantly higher serum total cholesterol levels in both women and men.

They also found a significant relationship between filtered coffee consumption and total cholesterol, but only among women, according to Åsne Lirhus Svatun, of the the Arctic University of Norway, in Tromsø, and colleagues.

“Doctors could become mindful of asking about coffee consumption when taking up the history of patients with elevated serum cholesterol,” said study author Dr Maja-Lisa Løchen.

“Guiding patients to change from plunger coffee or other unfiltered coffee types to filtered or instant coffee could be a part of a lifestyle intervention to lower serum cholesterol levels.”

The results were published in the journal Open Heart.

Previous studies of the relationship between serum cholesterol and espresso have had varying outcomes, the researchers note, adding given that coffee consumption is high worldwide, even slight health effects can have substantial health consequences.

“Coffee was included for the first time in the 2021 ESC (European Society of Cardiology) Guidelines on cardiovascular disease prevention in clinical practice,” they write. “Increased knowledge on espresso coffee’s association with serum cholesterol will improve the recommendations regarding coffee consumption.”

“I don't think that the findings in this paper are necessarily enough to change any advice about coffee,” said Dr David Kao, an associate professor of medicine at the University of Colorado Anschutz Medical Campus in Denver, in commenting on the findings. “This is partly because the most important thing, really, is whether subsequent events like heart attack or stroke increased or decreased. This analysis was not designed to answer that question.

“If one has to choose between this study, which would suggest drinking less coffee to maintain low cholesterol, and the others, which would suggest increasing coffee consumption might reduce risk of multiple kinds of CVD, one should choose the latter,” he said.

In the current study, the investigators assessed 21,083 participants in the Tromsø Study in Northern Norway. The mean age of the participants was 56.4 years. Using multi-variable linear regression, they compared the relationship between each level of coffee consumption with no coffee consumption as the reference point and serum total cholesterol as the dependent variable. They tested for sex differences and adjusted for relevant co-variates.

The findings indicate that drinking three to five cups of espresso each day was significantly linked with greater serum total cholesterol by 0.16 mmol/L (95% CI, 0.07 – 0.24) for men and by 0.09 mmol/L (95% CI, 0.01 – 0.17) for women in comparison with participants who did not drink espresso daily.

Compared with individuals who did not drink plunger/boiled coffee, consumption of six or more cups of plunger/boiled coffee each day was linked with elevated serum total cholesterol levels by 0.23 mmol/L (95% CI, 0.08 – 0.38) for men and 0.30 mmol/L (95% CI, 0.13 – 0.48) for women.

Notably, for women but not men, there was an increase in serum total cholesterol of 0.11 mmol/L (95% CI, 0.03 – 0.19) in association with drinking six or more cups of filtered coffee per day.

When excluding participants who did not drink instant coffee, drinking instant coffee yielded a significant linear pattern for both men and women, but there was not a dose-dependent association.

These data show that sex differences were significant for every coffee type except plunger/boiled coffee, the authors note.

Limitations of the study include its cross-sectional design; lack of generalisability of the data, given that the cohort primarily consisted of elderly adults and middle-aged white people; and the fact that the study did not adjust for all confounding variables.

Also among the study’s limitations were that some data were self-reported, and the missing indicator approach was implemented to assess data, the authors added.

Future research efforts should focus on following this cohort over many years to determine how consumption of various types of coffee is linked with events such as heart failure, stroke and myocardial infarction. This insight would be important in offering guidance on whether the style of coffee preparation matters, concluded Kao.

Study details
Association between espresso coffee and serum total cholesterol: the Tromsø Study 2015–2016

Åsne Lirhus Svatun, Maja-Lisa Løchen, Dag Steinar Thelle and Tom Wilsgaard.

Published in BMJ’s Open Heart on 10 May 2022

Abstract

Background
Coffee raises serum cholesterol because of its diterpenes, cafestol and kahweol, and the effect varies by brewing method. Population-based research on espresso coffee’s impact on serum cholesterol is scarce. Our aim was to examine how various brewing methods, in particular espresso, were associated with serum total cholesterol (S-TC).

Methods
We used cross-sectional population data from the seventh survey of the Tromsø Study in Northern Norway (N=21 083, age ≥40 years). Multi-variable linear regression was used to assess the association between S-TC as the dependent variable and each level of coffee consumption using 0 cups as the reference level, adjusting for relevant covariates and testing for sex differences.

Results
Consumption of 3–5 cups of espresso daily was significantly associated with increased S-TC (0.09 mmol/L, 95% CI 0.01 to 0.17 for women and 0.16 mmol/L, 95% CI 0.07 to 0.24 for men), compared with participants drinking 0 cups of espresso per day. Consumption of ≥6 cups of boiled/plunger coffee daily was also associated with increased S-TC (0.30 mmol/L, 95% CI 0.13 to 0.48 for women and 0.23 mmol/L, 95% CI 0.08 to 0.38 for men), compared with participants drinking 0 cups of boiled/plunger coffee. Consumption of ≥6 cups of filtered coffee daily was associated with 0.11 mmol/L (95% CI 0.03 to 0.19) higher S-TC levels for women but not for men. Instant coffee consumption had a significant linear trend but showed no dose–response relationship when excluding participants not drinking instant coffee. There were significant sex differences for all coffee types except boiled/plunger coffee.

Conclusion
Espresso coffee consumption was associated with increased S-TC with significantly stronger association for men compared with women. Boiled/plunger coffee was associated with increased S-TC in both sexes and with similar magnitude as shown in previous research. Filtered coffee was associated with a small increase in S-TC in women. Further research on espresso and S-TC is warranted.

 

Medscape article – Espresso Coffee Associated With Increased Total Cholesterol (Open access)

 

BMJ Open Heart article – Association between espresso coffee and serum total cholesterol: the Tromsø Study 2015–2016 (Republished under Creative Commons Licence)

 

ESC Guidelines on CVD prevention (Open access)

 

See more from MedicalBrief archives:

 

Up to three cups of coffee daily linked to significant health benefits — UK Biobank analysis

 

High coffee consumption associated with lower endometrial cancer risk – Meta-analysis

 

Daily tea and coffee consumption links to lower stroke and dementia risk — UK Biobank

 

Coffee consumption associated with lower liver stiffness — US national survey

 

Coffee a powerful addition to NAFLD treatment arsenal — Meta-analysis

 

 

 

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