Daylight saving hours, we can sometimes view as a blessing; other times, it’s a curse. Of course, this depends on whether the clocks are springing forward or falling back, of which the latter is favoured so we can enjoy an extra hour of sleep.
Disrupting our body clocks, or circadian rhythm, is far from beneficial. In fact, an increasing base of information demonstrates the potentially lethal effects of daylight saving hours. Questions arise as to why we still use this system, with many arguing that there are no advantages to outweigh the range of disadvantages. These are the lines of questioning we shall investigate in today’s blog.
So, what actually is daylight saving hours? First, we must understand what Universal Time Coordinated (UTC) is. Formally known as Greenwich Mean Time, UTC is the time zone that covers the UK, Ireland, Portugal and several Western African countries.
We abide by UTC throughout our winter season: from when the clocks go back an hour in October until they go forward an hour in March. When the hour springs forward on the last Sunday in March, we shift our time zone to British Summer Time (BST) for daylight saving. This means that BST is one hour behind our conventional UTC.
Daylight saving is to make better use of available daylight. Instead of having lighter mornings, putting the hour back allows us to have brighter evenings. This was said to help farmers after World War I, hoping to boost productivity in an industry that had been crippled. Since, however, this has been debunked as a myth. Farmers don’t change their routines when raising their livestock and crops in BST compared to UTC.
One of the main results of moving to daylight saving hours is disruptions in our circadian rhythm. But firstly, what is the circadian rhythm? One of the core biological systems that drives our sleep-wake cycle, it’s often referred to as an internal body clock. One of the main ways the circadian rhythm is regulated is through light.
So, what happens when we implement daylight saving hours every year? Our circadian rhythms become confused with the amount of sunlight we’re receiving and often cause them to become misaligned from our usual schedules. In other words, exposure to more morning darkness and evening light affects our tiredness. Evidence suggests that this does not shift for several months after adopting daylight saving.
Often referred to as ‘social jet lag’, it refers to the continual misalignment in timing between work and social obligations, and there are many health risks associated with this. For example, there’s an increased risk of heart disease, weight gain, type-2 diabetes, raised stress hormones and resting heart rate.
Overall, disruptions to the circadian rhythm are the basis for all the other risks we discuss below.
When BST switches to UTC in October, there’s an increase in road traffic accidents. With decreased visibility, the sudden evening darkness has proven to be more hazardous.
Similarly, studies have demonstrated that switching to or from daylight saving hours causes more workplace accidents with injuries of greater severity. One study found an increase in workplace injuries as high as 5.7%, resulting in over two-thirds of lost work days. Switching to daylight saving hours means we become more fatigued. As a result, we’re more likely to make poor decisions that could lead to injury.
Similarly, studies have demonstrated that there are increased rates of heart attacks associated with daylight saving hours. The same can be said with the rate of strokes, with a noticeable uptake in the first few days following the transition to daylight saving.
While many scientists are not sure of the specific reason that causes such an increase, many allude to the disruption of the circadian rhythm.
Given all we’ve discussed, finding any benefits outweighing these disadvantages is hard. Throughout the summer months, it’s significantly lighter in the evenings. People who work a 9-5 can benefit from enjoying the light and warmth in the evening. It’s also said that lighter evenings make it much safer. During UTC, the cold and darkness prevent us from enjoying the outside as much and is often unsafer. Aside from this, there aren’t other benefits to adopting daylight saving hours.
As we mentioned previously, the only reason we still use daylight saving time is to take advantage of the available daylight. Springing forward and falling back has become integrated into our way of living, and it can become quite hard to change something that is so incorporated systemically.
Daylight saving is primarily adopted in northern hemisphere countries, including most of North America, Europe and Egypt. A few places in the southern hemisphere implement daylight saving, but at the opposite time of year that northern hemisphere countries do. These include New Zealand, Paraguay, and some regions of Chile and Australia.
Most of Central and Latin America, Asia, and Africa do not observe daylight saving hours.
In light of everything we’ve discussed here, the disadvantages of daylight saving hours far outweigh the benefits. Arguably, the increase in heart attacks, strokes, traffic collisions, workplace accidents, and general circadian disruption is not worth enjoying more sunlight in the evenings.
While there’s not a huge amount we can do to change the system, there are some precautionary measures to offset the detrimental effects of the clocks springing forward. Check out our blog on ‘Adjusting To The Clocks Going Forward‘ for the best tips.