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Revitalising drinks 'don't boost alertness'
00:01am 21st July 2006

A study found that sugary drinks such as Lucozade and Coca Cola do little to boost alertness

Championed by Daley Thompson, Lucozade claims to revitalise both the body and brain. But those anxious to avoid nodding off might be just as well to drink glass of water, research shows.

The study found that sugary drinks such as Lucozade and Coca Cola do little to boost alertness.

Instead, they do the very opposite - they make you more sleepy.

Professor Jim Horne said that while the 'sugar rush' from sweet drinks may initially boost alertness, the effect wears off after around 15 minutes.

Those looking for a quick-fix to stave off sleepiness should instead reach for caffeine-rich drinks such as Red Bull or strong coffee.

Fitting in a quick nap also helps.

The Loughborough University sleep expert said the advice is particularly pertinent for motorists looking for something to keep them from nodding off at the wheel.

Those that pull up at a service station to buy a sugary drink will probably find the effects will have worn off within minutes of starting their journey again, he said.

'Very sugary drinks have a rebound effect - after an hour or so they make you even more sleepy,' he said. 'I would not advise Coca Cola or other drinks be used to combat sleepiness unless they contain adequate caffeine.

'A much better way to combat sleepiness is to have a drink that contains useful amounts of caffeine and combine that with a short nap.

He added that sugar-packed drinks such as Lucozade and Coca Cola are probably little better than water at keeping people awake.

The Department of Transport-funded study looked at whether Lucozade helped a group of healthy young men and women stave
off sleep.

The night before taking part, they had only been allowed to sleep
for five hours.

After a light lunch, the volunteers were given either a glass of Lucozade or a water-based low-sugar drink.

They were then monitored as they spent 90 minutes doing a computer test that measured their reaction time.

At first, there was little difference in the alertness between the two groups.

However, after around 50minutes, the alertness of the Lucozade drinkers started to fall. They started to feel sleepier than the other volunteers, had more lapses in concentration and made more mistakes.

Writing in the journal Human Psychopharmacology: Clinical and Experimental, Prof Horne's team said energy drinks may only ward of sleepiness in people suffering from hypoglycaemia - or extremely low levels of blood sugar brought on by fasting.

They said: 'It is clear that a 250ml energy drink given with a light lunch does not alleviate a moderate level of afternoon sleepiness.

'In contrast, after about an hour, sleepiness was significantly worse.

'Whilst there is good evidence that sugar intake can boost physical energy, there is little support for it having any benefits for a sleepy brain.'

by FIONA MACRAE, Daily Mail

找到藉口解釋上堂打嗑睡的原因, 看來要改變一下每日一支葡萄適的習慣.