Ferran Barbé, sleep researcher: ‘Changing the time impacts our mood and ability to focus for three days to a week’

Like every last weekend in October, Europe will set its clocks back one hour this Saturday, October 28. A week later, on November 5, the United States will follow suit: 3 a.m. will become 2 a.m. and dawn and dusk will come earlier. Although many people prefer the summer time, winter time raises health concerns among many experts; one of them is Ferran Barbé, professor of medicine at the University of Lleida (Spain) and one of the most influential researchers on sleep-related issues, according to Sleep and Breathing magazine. Barbé advocates keeping a fixed time throughout the year: winter time.

Question. How does changing the time impact health?

Answer. At an individual level, changing the time has a negative impact on attitude, mood, the ability to focus and the quality of sleep. It is estimated that it usually lasts between three days and a week, approximately, so there is no need to dramatize, but the consequences are there. There are various studies that associate time changes with an increase in cardiovascular problems and even traffic accidents, especially when the summer changeover takes place, which is the one that takes away an hour of sleep. This is because we are adapted to a rhythm of light and darkness that helps us secrete melatonin [a hormone that regulates sleep] and, when it suddenly shifts, we lose the ability to fall asleep.

Q. And why is winter time preferable to summer time?

A. Because of the biological clock. Waking up and starting the work day with sunlight makes melatonin disappear and helps us be more active. And the same thing happens in the afternoon; the longer the daylight hours become, the longer it takes to secrete the hormone. Besides, the time change was enacted in 1974 for economic reasons that had to do with the oil crisis, but at present, it has not been proven that greater energy efficiency is achieved.

Q. What population groups are the most affected?

A. Children and the elderly are more susceptible. The former because they need more hours of sleep and the latter because of their greater degree of general vulnerability. It must also be noted that this is more noticeable during the spring change, as a result of having one less hour to sleep.

Q. Beyond the time, what other factors alter the sleep routine?

A. The light stimulation from devices like computers, smartphones or tablets; eating a heavy dinner or playing sports in the three hours before going to sleep are factors that do not favor the secretion of melatonin. Also, temperature and external noise. All of these things cause insomnia, which affects almost 10% of the population and prevents quality sleep. And these problems are paid for in health: there is a greater risk of hypertension, diabetes, cardiovascular disorders and more.

Q. Socially, is sleeping a lot frowned upon?

A. It would seem like sleeping is synonymous with being lazy. But everybody has a biological sleep clock, which is genetic and immutable. Each individual’s needs are different, from four or five hours to eight or nine, and we must respect them if we want to be productive.

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