Effect of black tea consumption on radial blood pulse spectrum and cognitive health

- Black tea affects the arterial system and change the spectrum of pressure pulse.
- We proposed that black tea consumption increasing CBF may be one of possible mechanisms in lowering the risk of cognitive impairment and stroke.
- Among the short-term effects of black tea on blood pressure and pulse spectrum, caffeine effect is inevitable but not a dominant effect.
- Harmonic analysis could screen the overall impact of food or drug on arterial system along the time course.

Black tea consumption has been proven to improve endothelial function and to lower the risk of stroke and cognitive impairment. Several effects of black tea on cardiovascular system had been surveyed. However, the black tea effect on pressure pulse spectrum remains unknown. The study was aimed to investigate the influence of black tea on radial blood pressure and Pulse Spectrum. Fourteen healthy subjects received water and single doses of black tea (0.05 g/Kg) in separate weeks. The radial blood pressure and pulse wave were measured and the pressure pulses were evaluated using harmonic analysis. This report confirmed that black tea consumption (dose = 0.05 g/Kg) significantly increased third, fifth, (P < 0.1), sixth, seventh, and eighth harmonics (p < 0.05) of radial pressure wave comparing to water control. We proposed that black tea may increase cerebral blood flow (CBF), which was deduced from the results and from the conclusions of previous studies. The results also showed that the harmonic components of pressure pulse could be the vascular kinetic index that assessed the hemodynamic status in each time frame before and after consumption of black tea.