Fizzy drinks 'affect children's sleep'

The study looked at caffeinated soft drinks

Fizzy drinks can affect children's behaviour, scientists have confirmed.

Doctors in the United States say soft drinks with caffeine disrupt children's sleep and leave them feeling tired during the day.

The study of almost 200 teenagers found that boys are most at risk because they consume more soft drinks than girls.

The study has shortcomings

Spokesman, British Soft Drinks Association

Doctors said the findings raised questions over whether fizzy drinks should be sold in schools.

They also suggested that manufacturers should be forced to reduce caffeine levels in drinks or to stop targeting their products at children.

Less sleep

Dr Charles Pollak and colleagues at Ohio State University followed 191 teenagers between the age of 14 and 16 for two weeks.

They recorded their sleep patterns and daily intake of caffeinated drinks and foods.

They found that the average daily intake of caffeine was 63mg - the equivalent of half a cup of coffee.

Boys drank about 70mg each day compared to girls who consumed 55mg on average.

The doctors found that teenagers who drank larger amounts had disrupted sleep patterns.

They were more likely to wake during the night and to sleep less. In addition, they tended to be more tired during the day compared to those who drank less fizzy drinks.

Writing in the journal Pediatrics, Dr Pollak acknowledged that some teenagers may be drinking caffeine during the day to counteract poor sleep at night.

But he added: "Regardless of whether caffeine use disturbed sleep or was consumed to counteract the daytime effect of interrupted sleep, caffeinated beverages had detectable pharmacologic effects.

Caffeine limits

Dr Pollak suggested the steps should be taken to reduce the amount of caffeine consumed by young people.

"Limitation of the availability of caffeine to teenagers should therefore be considered," he said.

A growing number of schools in the UK and the United States have introduced bans on junk food and fizzy drinks.

Teachers at New End Primary School in Hampstead in London say a ban there has seen pupils' behaviour improve dramatically.

Staff at Charles Burrell School in Thetford in Norfolk say their water-only policy has helped pupils to concentrate and is improving their academic performance.

A spokesman for the British Soft Drinks Association criticised the study.

He said: "There are no grounds to suppose that fizzy drinks affect sleep. This study on the effect of the consumption of carbonated soft drinks on sleep patterns does not support the conclusion that there is any connection.

"The study has shortcomings. The authors of the study themselves accept that their research is inadequate."