The cumulative effect of coffee and a mental stress task on heart rate, blood pressure, and mental alertness is similar in caffeine-naïve and caffeine-habituated females.

Most North American workers drink coffee throughout their workday, although the cumulative effect of job stress and coffee is not well known. Research has shown that coffee affects the cardiovascular system and mental alertness primarily through the active ingredient caffeine; however, the dose of caffeine used in these studies is greater than a normal cup of coffee. In addition, these changes have been mostly determined in male caffeine-habituated consumers.