Doctors and teachers should be advising school children not to carry heavy book bags

Doctors and teachers should be advising parents and children about the risks of carrying heavy bags to school every day.

Research published in Archives of Disease in Childhood finds that teenagers are regularly carrying rucksacks to school which are far too heavy.

In the process they are experiencing back pain and storing up problems for the future researchers say.

Many children transport excessively loaded backpacks, which is harmful to a developing body, note the authors, who urge doctors and teachers to start advising parents and children on the risks of carrying heavy bags to school every day.

A total of 1403 Spanish school children took part in a back health assessment.

The teenagers were weighed with empty pockets and no coat but a school backpack.

The second time they were weighted without their rucksack.

A 61.5 per cent carried a backpack that was heavier than 10 per cent of their own body weight and 18 per cent carried a bag that was more than 15 per cent.

One in four teens said they had had back pain for more than 15 days in the previous year and those with the heaviest bags were 50 per cent more likely to have pain for more than 15 days.

The risk of pain increased with age and girls were more at risk of back problems than boys.