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The impact of an extra hour of sleep

Surrey’s pioneering sleep research featured on new BBC TV series Trust Me I’m A Doctor.

The program saw seven volunteers visit the Surrey Sleep Research Centre — home to forward thinking academics and leading research in the field of sleep and chronobiology — for an experiment into the effect of increasing average sleep by just one hour.

The volunteers, who normally sleep between six and nine hours a night, were randomly divided into groups. One group was asked to sleep for six-and-a-half hours a night — the amount of sleep the average Briton gets — the other for seven-and-a-half hours. After a week, blood tests were taken and the volunteers were asked to switch sleep patterns.

Computer tests revealed that most volunteers struggled with mental agility tasks when they had less sleep.

More importantly, the blood test analysis by Dr Simon Archer, Reader in Chronobiology, and the Surrey research team revealed that around 500 genes were switched on or off due to changes in the amount of sleep the volunteers had.

When the volunteers cut back from seven-and-a-half to six-and-a-half hours' sleep a night, genes associated with processes like inflammation, immune response and response to stress became more active. The activity of genes associated with heart disease, diabetes and risk of cancer also increased. The reverse happened when the volunteers slept for an extra hour. Learn more about Surrey research into sleep and gene activity.

Watch Trust Me I’m a Doctor on the BBC iPlayer and read more about sleep and chronobiology research at Surrey.

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