You don't need to drink that much coffee, researchers say

Looking for a way to cut down on coffee without falling asleep at work?

Researchers in the US have developed an app they claim can cut down your caffeine intake by 65 percent, without any corresponding loss in alertness.

The app asks users to input their sleep and caffeine schedules. It then uses an algorithm to work out the best times to make a cuppa to "optimise user performance for given times in the future".

"We found that by using our algorithm, which determines when and how much caffeine a subject should consume, we can improve alertness by up to 64 percent, while consuming the same total amount of caffeine," said Jaques Reifman, a senior research scientist at the US Department of Defence's Biotechnology High Performance Computing Software Applications Institute.

"Alternatively, a subject can reduce caffeine consumption by up to 65 percent and still achieve equivalent improvements in alertness."

He says the app, called 2B-Alert, will be useful for students, truckies, pilots and anyone else who wants to be awake and alert when they need to be, without having to drink too much caffeine.

Caffeine, the world's most popular stimulant, makes it harder to get to sleep. According to the University of Otago's Sleep Investigation Centre, it can take anywhere between 15 and 35 hours to eliminate caffeine from your system.

The centre recommends no caffeine within four hours of bedtime, and no more than 300mg a day - that's about three cups.

The 2B-Alert app hasn't been released publicly yet.