A study published in January in The Journal of the American College of Cardiology, for example, suggests that the amount of caffeine in two cu of coffee significantly decreases blood flow to the heart, particularly during exercise at high altitude.

• 比如说，刊登在1月份美国心脏病学会志上的一项研究结果认为，两杯咖啡中含有的咖啡因可以显著的减少流向心脏的血液，特别是在高纬度地区锻炼时。