The brief is available in French only. The English version will be available later this week.

Follow the Sun!

Natural time defined by the sun is the best option for health, mood, safety, education and productivity 

Why abolish Daylight Saving Time & maintain Standard Time?

The issue of time change is complex, but the evidence is clear: it is in the best interests of public health to abolish time change and maintain standard time permanently. Here are a few key points to help you understand what's at stake.

Why do we change the time?

Time change was introduced in Canada during the First World War to save energy. Today, with current lighting technologies, the energy savings resulting from the practice of time change are negligible (Kellogg and Wolff, 2008; Kotchen and Grant, 2008). It seems that the main reason why this practice is still ongoing is the fact that the state of New York still engages with this practice; some people are anticipating inconveniences due to misalignment with the New York Stock Exchange. Yet, the complications associated with the time difference with other regions are not insurmountable. Certain regions of Quebec, several American states (e.g. Hawaii, Arizona) and other parts of the world, such as Mexico, have clearly demonstrated that it is possible to manage this misalignment with the parts of the world that have not yet abolished DST. Ultimately, these logistic administrative complications have to be weighted against collective well-being and public health, which also bear some costs.

What are the impacts of the time change?

The biological clock regulates most of the body's physiological functions, forming a complex and delicate system that is synchronized predominantly by the light-dark cycle. This system maintains the proper functioning of hormone secretion, body temperature, metabolism and insulin regulation, heart rate and even gene expression, to name but a few. The synchronization of the biological clock requires light in the morning and darkness at the end of the day. The time change creates a mismatch between the biological clock, the schedule dictated by social constraints, and the light-dark cycle.

Scientific laboratory studies have shown that this type of shift notably causes an increase in heart rate, blood pressure and inflammation in the body, disrupts our metabolism and weakens our immune system.

Field studies report an increase in heart attacks, strokes, certain infections and immune-related diseases, digestive system problems, pregnancy and childbirth complications, and a deterioration in mental health, particularly with regard to anxiety and depression(Zhang, 2020). There is also a 30% increase in the risk of accidents and injuries, particularly on the road and in the workplace. All of this is avoidable.

We associate DST with the pleasures of summer (sun, vacations), but it's more than that!

Many people don't consciously feel the effects of the time change. Although not all the physiological effects are perceptible, they do alter body and brain function and increase health risks. It's critical to note that the time change doesn't affect everyone in the same way. Every year, the elderly, children and adolescents, and people with chronic illnesses suffer even greater impacts than the general population.

Considering Canada's northern position, another important parameter is latitude differences and the geolocation of time zones. Individuals living on the western edge of their time zone are the most affected, but the phenomenon is compounded by the fact that many regions of Canada have distorted time zones that are misaligned with solar exposure. For example, summer time, which lasts until November, means that many children have to go to school in the dark, and even have recess in the dark. Decisions concerning the time change must therefore aim for equity in health and well-being for all citizens, regardless of their age, health condition or where they live.

Time zones in Canada. In this updated map, note the very large time zones for Alberta and for Ontario and Quebec. (“Time in Canada”; https://en.wikipedia.org/wiki/Time_in_Canada (Map: MapGrid—Own work, CC BY-SA 4.0, https://commons.wikimedia. org/w/index.php?curid=94413574)

Why is it essential to stay on permanent standard time?

On winter days when the sun rises later, our biological clock is shifted later, causing a mismatch between our social clock and our biological clock. This forces us to get up earlier than when our body is ready. If we adopted permanent daylight saving time in winter, it would be even worse, as it would force us to wake up an hour earlier than we would on standard time. This would force most people to start school or work before sunrise for a third of the year. What people often don't realize is that it's morning light that's critical to well-being, health and productivity. By widening the gap between our internal biological clock and the social and environmental clocks, permanent daylight saving time creates a “social jet lag” associated with an increased risk of obesity, metabolic syndrome, cardiovascular disease, depression, as well as reduced performance and higher risks of accidents.

What can we learn from the experiences of others?

Many countries have questioned this practice and, in several cases, have considered or implemented its abolition and/or replacement by other time management practices. For example, in some countries that have tried to switch to permanent daylight saving time, there has been an increase in winter depression among teenagers, which diminished considerably after the return to permanent standard time. In Canada, some provinces are proposing to withdraw from daylight saving time and return to permanent standard time throughout the year, or to implement permanent daylight saving time.

Scientific evidence underlines the need to respect standard time throughout the year.

Resources

Webinar Recordings

 Let's Talk about Daylight Saving Time with Dr. Michael Antle, University of Calgary

Parlons de l'heure avancée avec Dr. Ashley Nixon, Conseil national de recherches Canada

Interviews 

Sleep tips to cope with time change in the fall

  • Gradually shift your sleep schedule

  • Maintain your regular sleep, eating and exercise schedules

  • With winter approaching, get as much light as possible in the morning

What if this is not enough? 

These tips may not be sufficient for everyone. The more pronounced impacts of time change on people with insomnia is a reminder that it is important to seek help when our sleep gets off track. There is more information on our website and self-help tools for those battling with insomnia.