Millions of people around the world start their day with a cup of coffee — but how does this popular beverage affect your blood pressure? Health experts and cardiologists say that coffee can cause a temporary spike in blood pressure, particularly in people who are caffeine-sensitive or those who don’t consume it regularly. The reason lies in caffeine’s stimulation of the nervous system, which can lead to a short-term increase in heart rate and vascular resistance. “Caffeine acts as a stimulant, triggering a surge in adrenaline, which may narrow blood vessels and temporarily raise blood pressure,” says Dr. Karen Phillips, a cardiovascular specialist. For most healthy individuals, this spike is modest and short-lived, usually lasting about 1 to 3 hours...