Key points: Around the world, coffee and tea are two of the most frequently consumed drinks. However, how much these beverages impact cardiovascular function in general, and coronary artery calcium in particular, is not well understood. A recent study, which aimed to understand this relationship further, concluded that moderate tea consumption may have a potential protective effect on by slowing calcium progression in the coronary arteries while coffee seems to have no clear positive, or negative, effects.
A recent study published in The American Journal of Medicine in February of 2017 by Dr. P. Elliott Miller, from the Department of Critical Care Medicine at the National Institutes of Health, examined coffee and tea drinking habits and coronary artery calcium deposits of over 6000 participants from the Multi-Ethnic Study of Atherosclerosis (MESA). Subjects’ consumption was evaluated by the following categories:
- Occasional (less than 1 cup per day)
- Regular consumption (1 cup per day or more)
Participants were tracked for a median of 5.3 years for coronary artery calcium outcomes and 11.1 years for cardiovascular events.
The results showed that participants who drank a cup of tea at least once daily had a decreased progression of coronary artery calcium compared to those who never drank tea; correlating with a statistically significant lower incidence of cardiovascular events.
In contrast, regular coffee drinkers did not show a statistical difference in coronary artery calcium or incidence of cardiovascular events as compared to those who did not drink coffee. The study did find, however, that caffeine intake was marginally inversely associated with coronary artery calcium progression.
This observational study showed that one cup of tea daily reduced coronary artery calcium progression and risk of cardiovascular events while coffee did not show a significant impact on coronary artery calcium status. Further studies are recommended to determine type of tea offering the most benefit as well as if a threshold exists as to where the benefits of tea consumption plateau or decrease.
Why is this clinically relevant?
- Drinking 1 cup or more of tea per day may slow progression of coronary artery calcium and significantly reduce incidence of cardiovascular events
- Coffee intake did not show a significant effect in reducing coronary events