How to maximise that caffeine buzz

Much like Ritalin for dreamy children, controlled levels of coffee consumption can make you work harder, faster and better then ever before. And, guess what, there’s a new app to help you do it.

A free app developed by Penn State University, Caffeine Zone iOS, is designed to tell you the ideal time to have your cup of joe.

Users enter information about their current caffeine consumption and the app correlates this with known facts about caffeine to graph how the stimulant will affect the person's system.

The beauty of it? It allows you to consume enough caffeine to kickstart the mental process keeping you in the “optimal alertness zone,” while preventing over-consumption leading to jitters and sleeplessness.

Scientists say people reach the “optimal alertness zone” once they have drunk 200 and 400 milligrams of caffeine, or four cups of instant coffee and a Red Bull.

"Many people don't understand how caffeine levels in their bloodstream go up and how they go down," said Penn State University professor Frank Ritter.

"It's important to understand the effect that caffeine can have at these various levels."