Coffee And Your Heart

An article published in The Journal of the American College of Cardiology (Jan. 2006) states that “Coffee limits blood flow to heart muscles during exercise.” The study analyzed blood flow to heart muscles among 18 healthy young volunteers during stationary bike exercise at room air and inside a chamber simulating a high altitude of 15,000 feet. All subjects took 200 mg of caffeine tablets (equivalent to two cups of coffee) and blood flow measurements were done with the PET scan.

The study findings reveals that blood flow patterns were not affected at rest but were reduced after exercise. And that, reduced blood flows were most pronounced at the high altitude level. Researchers analyzed that caffeine may block certain receptors in blood vessel walls interfering with the normal process by which adenosine signals blood vessels to dilate during exercise.

The study results may not be significant among healthy individuals taking coffee but may be a concern with people who have coronary heart disease or CHD.