IT doesn't matter if they love a latte or reach for an espresso skipping that morning cup puts most coffee-lovers in a bad mood for the rest of the day.
And it's not just sluggishness and lack of energy that strikes when you go without.Scientists have discovered that saying no to the first coffee of the day can even impair your memory.
The Australian study found that caffeine cravings are similar to the effects of heroin and cocaine withdrawal, which use up valuable brain space.
This means that the effort required by the brain to repress the urge for caffeine leaves fewer cognitive resources for taking in information.
A study of 55 coffee drinkers by the University of Tasmania found those denied the drink for around 12 hours scored significantly lower in a test of 100 word pairs.
In fact, compared to the coffee drinkers allowed to have a cup, those suffering cravings had close to a 50 per cent lower proportion of correct responses. However, those who scored badly thought they had done just as well as usual.
Previous research has shown that heavy coffee drinkers pay exaggerated attention to the drink in a similar way drug users do to heroin and cocaine.
The study, published in the journal Memory, states that coffee-drinking, when it becomes a habit, requires cognitive processing in the brain to stop people picking up a cup of coffee.
It is this extra activity which leaves less space for other tasks, meaning it is harder to remember things.
© Daily Mail