Energy drinks improve response time, but effect shrinks as dosage rises: study

TORONTO - Imtiaz Miah knows that excessive caffeine consumption isn't good for his health, but the fourth-year electrical engineering student at Ryerson University turns to caffeinated drinks to stay mentally alert to get his schoolwork done.

A recent study confirms that small doses can improve alertness and decrease response times on a test measuring behavioural control.

But many experts are still concerned about consumption of sugary energy drinks by adolescents and college students and are calling for more research.