If your early morning nursery or school routine doesn’t start until you’ve had your cup of coffee, it may surprise you to hear that your first sip of the black stuff makes no difference to your daily alertness. It’s apparently all in your mind!

The stimulating effect that coffee gives its drinkers in the morning is simply the body relieving overnight caffeine withdrawal. This means that while it may feel like it’s setting you up for the day, it’s only bringing your body back to its ‘normal’ level of alertness rather than enhancing it.

“Although frequent users feel alerted by caffeine, especially by their morning coffee, evidence suggests that this is actually merely the reversal of fatiguing effects of acute caffeine withdrawal,” says Peter Rogers from Bristol University.

Bristol University researchers studied 379 caffeine and non-coffee drinkers and they found that there were no differences in alertness between the two. They also found that non-coffee drinkers experienced headaches and anxiety after drinking coffee, but felt no more alert than usual.

Not everyone agrees that coffee doesn’t wake us up in the mornings, however. “There is overwhelming wealth of evidence that caffeine does increase alertness levels by acting as a stimulant on the central nervous system by prompting the release of adrenaline,” says Dr Euan Paul from the British Coffee Association. How many cups of coffee do you drink to get you through the day?