The most popular reason is increased alertness and wakefulness. As long as you consume caffeine in moderation, you should be fine. Caffeine is one of the most commonly used stimulants by athletes. This is because it can give you an adrenal boost that can improve athletic performance. Caffeine creams are another positive use of caffeine. These can be applied to the skin to reduce redness and itching. Believe it or not, caffeine can improve airway function for up to four hours in people with asthma. Study shows that taking 200 mg of caffeine by mouth daily may improve memory in some people with extroverted and academic personalities.