The clocks are going forward this weekend, marking the start of British Summer Time (BST).
Britons will lose one hour’s sleep when they wake up on Sunday morning, but according to a study there is a more serious health risk than tiredness.
And it is not Sunday people should be worried about, but the Monday. The Monday after the daylight-saving time change will see the risk of having a heart attack jump up by 10 per cent.
Scientists at the University of Alabama, in the United States, said the daylight-saving time change coupled with sleep deprivation results in the risk of suffering a heart attack.
“The Monday and Tuesday after moving the clocks ahead one hour in March is associated with a 10 per cent increase in the risk of having a heart attack,” said Associate Professor Martin Young, PH.D., in the Division of Cardiovascular Disease.
“The opposite is true when falling back in October. The risk decreases by about 10 per cent.”
Interestingly, the Sunday morning of the time change does not affect many people’s schedules. It is the Monday when the majority of people are getting up early to go to work that the heart attack risk peaks.
“Exactly why this happens is not known but there are several theories,” Professor Young, speaking to The Telegraph, added.
“Sleep separation can alter other body processes, including inflammatory response, which can contribute to a heart attack.
“And, your reaction to sleep deprivation and the time change also depends on whether you are a morning person or night owl.”
According to the professor, every cell in the body has its own clock that allows it to anticipate when something is going to happen and prepare for it.
When there is a shift in one’s environment, such as springing forward, it takes a while for the cells to readjust.
“The internal clocks in each cell can prepare it for stress or a stimulus. When time moved forward, cell clocks are anticipating another hour to sleep that they won’t get, and the negative impact of the stress worsens; it has a much more detrimental effect on the body.”
The body’s clock eventually syncs with the environment.
The March equinox is the date used by astronomers to mark the start of spring in the northern hemisphere, signalling the beginning of longer days ahead and, hopefully, warmer weather to come.
The actual date of the first day of spring changes every year as it is based on the astronomical calendar.
So when is it this year?