Espresso coffee increases total serum cholesterol levels to similar levels as boiled/plunger coffee and to a larger degree in men than women
Drinking espresso coffee raises serum total cholesterol levels to a similar extent as boiled/plunger coffee and this effect is greater in men compared to women. This was the conclusion of an analysis of data in the Tromsø Study in Northern Norway by researchers from both Norway and Sweden.
Coffee is one of the most widely consumed beverages in the world and data for 2020/21 show that around 166.63 million 60 kilogram bags of coffee were consumed worldwide, which represents a slight increase from the previous year. Moreover, an umbrella review of studies on coffee consumption concluded that the beverage seems generally safe within usual levels of intake and shows large risk reductions for various health outcomes at three to four cups a day, and is more likely to benefit than harm health. Nevertheless, evidence first observed in 1983, suggested that coffee drinking increased total cholesterol level when compared to non-drinkers. Despite this potential harmful effect of higher cholesterol levels, a 10-year study revealed a J-shaped association between daily coffee drinking and the risk for a first cardiovascular disease event. One possible explanation for this apparent paradox was the method of coffee brewing and one study with over half a million individuals followed for over 20 years, found that an unfiltered brew was associated with higher mortality than filtered brew. Unfiltered brews include espresso coffee but this contains the diterpines kahweol and cafestol, both of which have been shown to raise serum cholesterol. However, the adverse health effects of espresso coffee are uncertain, with one study finding no effect on blood levels of total cholesterol, HDL-cholesterol and LDL-cholesterol whereas another, found that while consumption of more than 2 cups/day of espresso coffee was associated with an increased CHD risk, the coffee was not associated with changes in plasma lipid.
For the present study, the researchers turned to data obtained from the Tromsø Study to further examine the association between espresso coffee intake and increased serum cholesterol levels. As the study also held information on both the quantity and type of coffee consumed (e.g., filtered, instant etc), the researchers were able to categorise consumption of each coffee type. This was recorded as 0 cups, 1–2 cups, 3–5 cups and ≥6 cups daily. Demographic and clinical data such as co-morbidities were also recorded and adjusted for in the analysis. The team used linear regression to determine the association between coffee type/intake and serum cholesterol levels.
A total of 7167 individuals with a mean age of 56.4 years were included in the analysis. Overall, women drank a mean of 3.8 cups of coffee/day compared to 4.9 cups/day for men.
Men who drank 3 – 5 cups/day of espresso coffee had a 0.16 mmol/l (95% CI 0.07 – 0.24) higher serum total cholesterol level compared to men who did not drink espresso coffee. However, when compared to men who drank > 6 cups/day, the serum cholesterol levels were similar (0.14 mmol/l) in comparison to non-drinkers. Women drinking 3 – 5 cups/day of espresso coffee had a 0.09 mmol/l (95% CI 0.01 – 0.17) higher cholesterol level compared with non-drinkers.
For boiled/plunger coffee consumption, men drinking 3 – 5 cups/day had a 0.22mmol/l higher serum cholesterol, and women drinking the same amount had a 0.18mmol/l higher level when both were compared with non-drinkers.
For filtered coffee, men drinking 3 – 5 cups/day had a 0.04mmol/l and women a 0.08mmol/l higher cholesterol level compared to non-drinkers. Finally, for instant coffee, men drinking 3 – 5 cups/day had 0.02mmol/l and women a 0.12mmol/l higher cholesterol compared to non-drinkers.
The authors concluded that both espresso and boiled/plunger coffee increased serum cholesterol levels, with a greater effect in men than women, but that this increase was higher than for either filtered and instant coffee. However, the researchers were unable to adjust their results for milk and sugar intake which might also have affected the results. Furthermore, they also recognised that the cross-sectional nature of the study limited the causal inference; in other words, the study design made it impossible to have any certainty over their findings.
Svatun AL et al. Association between espresso coffee and serum total cholesterol: the Tromsø Study 2015–2016 Open Heart 2022