Daylight Saving Time and Its Impact on Our Sleep

Patricia Yarberry Allen, M.D. is a Gynecologist, Director of the New York Menopause Center, Clinical Assistant Professor of Obstetrics and Gynecology at Weill Cornell Medical College, and Assistant Attending Obstetrician and Gynecologist at New York-Presbyterian Hospital. She is a board certified fellow of the American College of Obstetrics and Gynecology. Dr. Allen is also a member of the Faculty Advisory Board and the Women’s Health Director of The Weill Cornell Community Clinic (WCCC). Dr. Allen was the recipient of the 2014 American Medical Women’s Association Presidential Award.

Since my flight to a family birthday party in early February, I have been very focused on infection control in my personal life and on formal training for the staff of my medical practice to improve their health while commuting to work. We have had formal reviews of infection control procedures for Coronavirus-19 so that we can create a safe and healthy environment in the office for patients and staff. I implemented hand washing training and effective cough and sneeze control for The Husband that did not go well. I have been talking to myself while walking to and from work each day: “Do not touch your face, do not touch your face.” I had just begun to catastrophize less and be more rational when on Saturday The Husband told me “Remember tomorrow is Spring Forward Day.” This is the first time I did not agonize for weeks about the loss of an hour from the time change. I had forgotten! It arrived anyway: Sunday, March 8th at 2 a.m.

I counsel patients to prepare for this alteration in our sleep cycle by making small changes in their internal clock before the big morning comes by waking up a few minutes earlier each day for a month. I also encourage patients to wake up with gratitude, begin salutations to the sun with meditative breathing exercises, and start the day with positive thoughts. But, today the physician cannot take her own advice. I certainly didn’t prepare my internal clock to gradually change over the course of the last month and I did not wake up with a salutation to the sun.

Today is the worst day of the year for me.  It is the first work day after the “spring ahead” impact of Daylight Saving Time (DST). Currently adopted in more than 70 countries, DST  imposes a twice-yearly one-hour change in local clock time. The start of Daylight Saving Time in the spring leads to the loss of one hour of sleep on the night of the transition, but its impact on the following days continues.

Today is the day that I had to begin my workday one hour early, and in darkness, I might add.  Apparently the purpose of Daylight Saving Time is to save electricity because it provides more hours of natural light. I still don’t understand how I am saving electricity by wandering around with the lights on for an hour longer every morning. My hour of morning light has been moved to the evening for people who want to walk or bicycle in the evening light. I wish these people would just go to the gym or do a Jane Fonda workout video indoors and leave my morning hour of sleep alone.

Experts who study circadian rhythms and sleep disorders understand that the symptoms I experience at the start of Daylight Saving Time each year are not unusual.  I just complain about the symptoms more than most people do. I have anxiety about the loss of my hour of morning sleep for weeks before the dreaded change in the clocks occurs; and then I suffer from sleep deprivation symptoms for a week after the change.  I consume more coffee to overcome daytime drowsiness and then take more drugs to prevent the destruction of my stomach lining from the coffee. And I am certainly cranky.

Studies and personal anecdotes supporting the destructive impact of this antiquated idea are legion. Daylight Saving Time has been documented to alter sleep patterns for weeks, affecting mood, job performance, health, and the severity of auto accidents.

In its October 30, 2008, issue, The New England Journal of Medicine reported the results of an epidemiological review of all the heart attacks in Sweden from 1987 to 2006. The authors, Richard Ljung and Imre Jansky, discovered a slight increase in heart attacks in the first three working days after clocks were set ahead for the beginning of Daylight Saving Time in the spring and a similar decrease on the Monday after clocks were set back for the end of DST in the fall. And, wouldn’t you know it? Women seemed to be slightly more at risk than men for heart attacks in the spring.

From the studies, we know: 

  • Sleep deprivation increases the risk factors for heart attacks, including high blood pressure, the production of toxic inflammatory proteins, and obesity.
  • In addition, with this loss of a morning hour, our bodies lose an hour of preparation for the inevitable rise in cortisol and other hormones and chemicals that  prepare us to begin our day. Many of these can also cause stress on an already damaged cardiovascular system.
  • Sleep is necessary for the proper control of the internal clock of every cell in the body.  With the change in the sleep-wake cycle, there is an increase in the production of chemicals that affect inflammation and the immune system.
  • Morning light is the most important light for synchronizing our circadian rhythms.  Of course, Daylight Saving Time takes away an hour of morning light. This increases the risk of seasonal affective disorder and, in some people, depression.
  • A study based on suicide data in Australia from 1971 through 2001 confirmed that male suicide rates rose in the weeks following the change to Daylight Saving Time, compared with the weeks following the return to standard time and the rest of the year.

We are in an unprecedented moment of global crisis as we navigate COVID-19. We need to be rested since sleep improves our immune system. Be careful this week. Scale back commitments. Be more mindful of accident prevention. And, practice really good sleep habits as well as hand washing hygiene. 


Start the conversation

This site uses Akismet to reduce spam. Learn how your comment data is processed.