Moderate tea consumption was associated with a slower progression of coronary artery calcium and lower incidence of major cardiovascular events, a study published in the American Journal of Medicine has found. Regular coffee consumption had neither protective nor adverse effects.

The tea and coffee drinking habits of 6,508 participants in the Multi-Ethnic Study of Atherosclerosis were analysed. Intake of each drink was classified as never, occasional (< 1 cup/day), and regular (≥ 1 cup/day).

A coronary artery calcium progression ratio was derived and data analysed for any association between beverage intake and incident cardiovascular events.

The study participants were followed up for a median of 5.3 years for coronary artery calcium and 11.1 years for cardiovascular events.

Those who regularly drank tea (≥ 1 cup/day) had a slower progression of coronary artery calcium compared with never drinkers after multivariable adjustment. This correlated with a statistically significant lower incidence of cardiovascular events for ≥ 1 cup/day drinkers: hazard ratio HR 0.71 (95% CI: 0.53-0.95).

With respect to coffee, compared with never coffee drinkers, regular coffee intake (≥ 1 cup/day) was not statistically associated with coronary artery calcium progression or cardiovascular events: HR 0.97 (95% CI: 0.78-1.20).

The authors conclude that moderate tea drinkers had slower progression of coronary artery calcium and reduced risk for cardiovascular events but that these findings did not apply to coffee. However, no harmful affect was found from moderate coffee intake.

It would appear that more research is required to try to understand the potentially protective nature of moderate tea consumption.

Dr Peter Savill

Miller PE, Zhao D, Frazier-Wood AC et al. Associations of coffee, tea, and caffeine intake with coronary artery calcification and cardiovascular events. Am J Med 2016 Sep 15. pii: S0002-9343(16)30925-1. doi: 10.1016/j.amjmed.2016.08.038.