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Health Effects of Daylight Saving Time

Does losing one hour of sleep really matter? Experts say yes. Learn how your health could be affected and what you can do to rebound from Daylight Saving Time.

As we tiptoe toward warmer seasons and get ready to spring our clocks forward this weekend, it seems timely to discuss the health effects of daylight saving time (DST).

We’ve all heard the typical gripes about DST, usually regarding children being tossed off their routine, but not many people discuss the true health risks that come with the time change, specifically in the spring when we lose an hour of sleep. Seems minor but we've all heard about the butterfly effect!

Let’s touch on the health risks (and surprise: benefits!) of DST and what we can do to offset this disruption to our biological clocks.

There are four buckets of “elevated risk clusters” because of DST, as the National Institutes of Health (NIH) describes:

  • Ischemic heart disease, such as heart attacks
  • Accidents and injuries
  • Mental and behavioral disorders, specifically substance abuse
  • Immune-related diseases such as colitis and enteritis


On the flip side, there’s one health area in which we benefit that surprised researchers:


While long-term stress suppresses the immune system, short-term stress (like DST) has been found to enhance the immune system. Your body appears to give you a little boost while it can! If you fall into this bucket, I hope you enjoy a week of reprieve.


Let’s dive deeper into each risk cluster.

Risk cluster #1: Ischemic heart disease, such as heart attacks

The NIH study found an increase in heart attacks in both men and women over the age of 60 in the week following DST. If you have zero cardiac risks*, you are likely not included in this bucket.

Regardless, let’s not panic but instead, remind ourselves what symptoms we need to be on the lookout for and when to seek help.

  • Chest pain or discomfort that may even come and go. It can be described as squeezing, pressure, fullness, heavy or painful.
  • Pain or discomfort in other areas of the body - jaw, neck, stomach, back, or one or both arms.
  • Shortness of breath, with or without any chest pain.
  • Nausea or vomiting, breaking out in a cold sweat, lightheadedness or dizziness.

Remember, women are more likely to experience some of these atypical signs of a heart attack. If you aren’t sure, reach out for help.

*Know how to reduce your cardiac risk level:

  • If you smoke, do your best to quit
  • Exercise for at least 30 minutes per day
  • Maintain a healthy weight
  • If you’re diabetic, control your blood sugar
  • Limit alcohol intake to 2 drinks for men and 1 for women per day
  • Manage stress by getting outside, walking, yoga, meditation, a warm bath - whatever helps relax you
  • If you have high cholesterol and/or blood pressure, ensure they remain controlled with the above tips or your prescribed medication


Risk cluster #2: Accidents and injuries

The NIH study found that children and young adults from 0-20 years old were more likely to experience injuries of the head, wrist, and hand following DST. Adults 41 years and older were more likely to experience injuries of the lower torso or chest.

Car accidents are also more likely following DST with an increase of 16-30% on that first day (Sunday) and +12% on the day following (Monday).

I share these stats with you because I find it so interesting that losing one hour of sleep has such an effect. With this knowledge, accidents are avoidable! Simply take extra precaution with home projects or running errands, just like you’d do if you were heading out in bad weather or on holidays. Grab an extra cup of caffeine and keep your distance from other cars on the road.

Risk cluster #3: Mental and behavioral disorders, specifically substance abuse

DST has shown an increase in psychoactive substance use, especially in males ages 41-60 years old. Let me tell you, the tangled web of studies surrounding circadian disruption, sleep disturbance, and substance abuse is…tangly. In an attempt to sum this up, I’d say:

  1. In general, it’s shown that drug users have disrupted sleep-wake cycles, so the increased disruption of DST is believed to lead to increased vulnerability for substance abuse.
  2. Check on your friends and on yourself. Anyone with a history of drug or alcohol abuse may need some extra support following DST to stay on the straight and narrow.


Risk cluster #4: Immune-related diseases such as colitis and enteritis

Stress-related GI issues, such as Crohn’s disease and ulcerative colitis, were found to increase in women over 60 years old and in boys under 10 years old. Weird, I know.

Again, if you don’t currently experience any of these GI issues, I don’t suspect DST will have an effect on you. But if you do, or you have a son susceptible to these, awareness always feels empowering. You likely know how to work through these flare-ups so make sure you have the foods available that may lessen symptoms and you’re stocked up on the medication you need.

The biggest takeaways that jump out at me as I read through DST health effects are:

  • Sleep is serious business
  • Losing sleep activates a stress response
  • Stress responses manifest in many ways in the body, from heart attacks to Crohn’s flare-ups or car accidents and drug relapses or even a quick boost to the immune system that ends up helping us


I think we all experience bad nights of sleep that have these same effects but that’s harder to study. It’s easier to look at a quarter of the world’s population at once who are all affected by DST. Let’s all take this as a reminder to eat well, manage our stress, and get plenty of sleep each night. And let’s enjoy the extra evening sunlight, shall we? I know that does wonders for my stress levels.