Drinking coffee with sugar boosts memory and attention span

A cup of coffee is what millions of us rely on to kick-start the day. But new research shows that morning pick-me-up has a much more potent effect on the brain if it is taken with sugar. Scientists at the University of Barcelona in Spain found taking caffeine and sugar at the same time boosted the brain’s performance more than taking them on their own. Researchers now believe each one boosts the effect of the other on brain functions such as attention span and working memory.

The findings come from brain scans carried out on 40 volunteers who were tested after they had coffee with sugar, coffee without sugar, sugar on its own or just plain water. The results, published in the journal Human Psychopharmacology: Clinical and Experimental, suggest sugar-sweetened coffee may be the best way to prepare the brain for a busy day ahead. But it’s likely that coffee lovers who do not take sugar will get the same benefits from enjoying a sugary snack with their drink.

According to the British Coffee Association, UK consumers drink approximately 70million cups of coffee a day. More than half add sugar. It is well known that caffeine is a stimulant which works on the brain and can combat drowsiness and fatigue.

Previous studies have even suggested three cups of a coffee a day can significantly reduce the risk of Alzheimer’s disease, possibly by triggering a chain reaction in the brain that prevents the damage done by the disease. It’s also well known that glucose, a type of sugar, is the main fuel which brain cells need to function properly. But the latest research indicates the two complement each other when it comes to bolstering the brain’s performance.

Researchers performed MRI scans on patients’ brains as they carried out a standard task designed to check their attention span and working memory. The tests were performed after they had consumed each of the drinks. Results showed that when the volunteers drank coffee with sugar there was reduced activity in the bilateral parietal cortex and the left prefrontal cortex - the two parts of the brain responsible for attention and memory.

But while activity levels dropped, the brain’s performance did not. Researchers said this shows the brain operates more efficiently when it has had a caffeine and sugar boost. ‘The two substances improve cognitive performance by increasing the efficiency of the two areas of the brain responsible for sustained attention and working memory,’ said researcher Dr Josep Serra Grabulosa. ‘The brain is more efficient under the combined effect of the two substances, since it needs fewer resources to produce the same level of performance than when volunteers took only caffeine, glucose or water.'