Clock Change Could Cut Obesity

10 November 2011, 06:00

Child obesity in Britain could be reduced if the clocks did not go back in the winter, a study has found.

Researchers said the study, which concluded that children are most physically active on longer days, adds evidence in favour of a Daylight Saving Bill which could bring the UK into line with Central European Time (CET) for a trial period of three years.

Scientists at the London School of Hygiene and Tropical Medicine said that children aged eight to 11 were most active between 5pm and 8pm during lighter evenings.

They measured the body movements of 325 children in Hertfordshire in their daily routine for 817 days over the four seasons and found children were most active on days with 14 or more hours of daylight.

Authors of the study, which is published in the Journal of Physical Activity and Health, said the trend remained constant - regardless of the weather.

On long days, the children spent 22% of their time taking part in ``out-of-home play'' in afternoons and early evenings, while the figure decreased to 13% when the day became shorter.

Researcher Dr Anna Goodman said: “The fact that kids spend more time playing outdoors and are more physically active overall on these longer days could be important at a population level for promoting their fitness and in preventing child obesity.

“This strengthens the public health argument for the Daylight Saving Bill currently under consideration by the House of Commons, which proposes putting the clocks forward by an extra hour all year round.”

British Summer Time ended Sunday 30 October at 2am when the clocks went back by one hour.

The new Daylight Saving Bill, tabled by Rebecca Harris, Conservative MP for Castle Point in Essex, calls for a review of the potential costs and benefits of a move to CET and would need further legislation before any trial was launched.

Moving to CET would mean lighter winter evenings, which supporters claim would cut road deaths, boost tourism and reduce energy use.

But any change is likely to face opposition from many in Scotland who do not relish the prospect of an extra hour of darkness in the morning.

Debating the effects of turning the clocks back has been a British pastime since at least 1908, when the first Daylight Saving Bill was brought before the House of Commons.

During the Second World War the Government moved the clocks forward one hour to help munitions factories maximise productivity and allow people to get home safely before the blackout.

Between 1968 and 1971 the Government carried out the same experiment but was forced to end it after complaints in Scotland and northern England.