Daylight Savings Time (DST) initially was suggested by Teddy Roosevelt during World War I to conserve fuel needed in the war. DST was reinstated for a year during the World War II Era until September 30, 1945. It was not, however, until 1966 that Congress passed legislation and imposed their own “standard” time on states. As a result of this legislation, between March and November, all states, with the exception of Hawaii and Arizona, now turn their clocks ahead one hour. But today, sixty-per cent of the world follow standard time all year long. As a result, many U.S. citizens (feeling the loss of that one hour of sleep) and their states are questioning the impact that changing clocks appears to have on their health.
Phyllis C. Zee, MD, PHD, sleep medicine specialist and chief of Sleep Medicine in the Department of Neurology at Northwestern Medicine, states “The science has evolved over the last decade to show the transition between standard time and DST is associated with adverse health consequences.”
She continues “The big question…right now is, should it be permanent standard time or permanent DST?”
Dr. Zee shares her reasons for moving to year-round standard time in the next three paragraphs.
With the loss of one full hour of sleep, the body’s natural 24-hour biological cycles (the circadian rhythm) are exposed to less morning light and more evening light. This can cause a person to feel tired in the morning and awake in the evening. Dr. Zee comments, “If we adopt permanent standard time, our internal clocks will more likely be in sync with the rotation of the Earth, seasonal changes and the sun clock.”
Sleep deprivation is known to be bad for our cognitive and physical health, creating short-term health problems with sleep issues and fatigue (such as jet lag) and blood pressure changes. The sleep medicine specialist adds “Late starters…are more vulnerable to these effects because they already sleep through more hours of natural morning light.” Studies show that DST is associated with depression, cluster headaches, weight gain, and slowed metabolism.
Seasonal disorders have been linked to an increased risk of developing cognitive and mental health disorders, as well as heart and digestive diseases. DST can make these problems worse, if you already have them. The research shows that DST, during the week after the shift, will present these figures:
Cardiovascular disease: 24% higher risk of heart attacks
Injuries: Include a 6% spike in fatal car accidents
Stroke rate: Increases by 8%
Mental health and cognitive issues: 11% spike in depressive episodes
Digestive and immune-related diseases (such as colitis): An increase by 3% in females over the age of 60
Dr. Zee concludes with advice that we should:
1. Make a conscious effort to protect our circadian rhythm through keeping a sleep routine that gives us 7-9 hours of sleep.
2. Spend as much time outside in the morning hours, as possible, to gain the natural morning light and further preserve our circadian rhythm.
3. Avoid excessive amounts of caffeine, as well as alcohol and blue light exposure, shortly before going to sleep.
4. Engage in morning exercise to raise our body temperature, increase our wakefulness, and help us to reset our internal clock.
