The study, which surveyed 688 students with an average age of 22, showed that male subjects showed greater levels of alertness than women - though a study on decaffeinated coffee showed just the opposite. The reasons for this are still unclear, what is clear, is that in previous studies it was believed that caffeine initiated its stimulatory effects between 30-45 minutes. This new study found that effects can be seen as quickly as in 10 minutes.
Log in