Should the clock be ticking on daylight saving time?

As we gain an extra hour, some experts believe the abolition of bi-annual time changes would save lives and prevent disorientation among dementia patients. By Hanna Geissler

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Id you remember to put your clock back last night? If so, you may have felt different this morning. The twice-yearly shift between Greenwich Mean Time and British Summer Time - when we lose or gain an hour - can have small but noticeable effects on our health. So much so that some experts are calling for it to be scrapped completely.

Germany was the first to implement daylight saving time (DST) in April 1916 to conserve energy during the First World War. A similar change was temporarily introduced in Britain weeks later. The current arrangement of clock shifts eventually began in 1972 with the British Summer Time Act.

An hour may not seem much but the change can disrupt circadian rhythms - the body's internal 24-hour clock that regulates physical, mental and behavioural changes.

Time shifts can be particularly disorientating for people with dementia who sometimes experience confusion, agitation and anxiety later in the day, a phenomenon known as sundowning.

Each year, dementia charities issue advice on helping loved ones deal with the clocks changing using techniques such as distraction, sticking to an evening routine and limiting intake of caffeinated drinks.

Poor sleep caused by DST has been found to worsen depression, anxiety, and seasonal affective disorder, and has been linked to a temporary rise in traffic accidents. And the American Heart Association has warned of an increase in heart attacks and strokes in the days after the clocks spring forward. A study of hospital admissions across Michigan found a 24% increase in heart attacks on the Monday following the switch. This is thought to be caused by stress on the cardiovascular system which can trigger a short-term spike in blood pressure, heart rate and stress hormones.

Author and sleep expert Charlie Morley is among those calling for the clock changes to be abolished. He likens them to "imposing a mini jet-lag on the whole nation".