Daylight saving time (DST) occurs twice yearly, in March and November. The purpose of DST is to make the most of natural light, since days in spring, summer, and early fall stay lighter longer compared to days in late fall and winter. While it may seem like an insignificant change, DST can actually affect your health. Our bodies keep track of time, and any changes in daily patterns can trigger stress on our brains, leading to sleep deprivation, depression, and more.
How DST affects sleep
We are guided by circadian rhythms, which are cycles our bodies use to regulate sleep, appetite, and mood. Because these rhythms are dependent on light exposure, they must be synchronized with natural light and darkness cycles to ensure high-quality sleep.
What does this mean? When we “spring forward,” or set our clocks forward an hour, it’s darker in the morning (when you need to wake up), and lighter at night (when you need to fall asleep). This can make it harder to fall asleep or wake up at your normally scheduled time.
We are most vulnerable to sleep deprivation during DST in March. One study, conducted by the American Psychological Association, found that on the Monday after springing forward, the average person receives 40 minutes less of sleep. While most people seem to adjust within a few days, some may feel the effects for months. This can throw off other functions in your body.
Other health hazards
When your circadian rhythm is thrown off, it can lead to more serious health problems. DST has been linked to an increased risk of developing certain disorders and diseases, including cardiovascular disease, stroke, mental health and cognitive issues, and digestive and immune-related diseases. If you already have these conditions, DST can make them worse.
The transition through DST can create short-term health problems like fatigue and changes in blood pressure. It has also been linked to long-term health effects like depression, slowed metabolism, weight gain, and cluster headaches. These effects are mostly felt by those who tend to wake up later in the morning or stay up later at night, such as teenagers.
People who normally get less than the recommended amount of sleep are also more likely to notice these effects. This includes people who have demanding school, sports, social, and work schedules.
Tips to combat DST
Leading up to DST, you can make subtle changes to your routine to help prepare yourself for the time adjustment.
- Go to bed early. Since your circadian rhythm will be disrupted, trying to fall asleep earlier can help you adjust easier when DST comes. Aim to go to sleep 15-20 minutes earlier leading up to DST.
- Sleep in. The day after DST is a Sunday, so sleeping in for an extra half hour can help your brain and body adjust more quickly.
- Expose yourself to light. When you wake up after DST, turn on the lights immediately. Avoid lying in bed or getting ready in the dark. This can trick your internal clock into believing it’s nighttime. Spending time outside during the day can help reduce feelings of tiredness. Exposing yourself to daylight suppresses melatonin, the hormone that makes you feel tired.
- Keep it dark at night. Similarly, when you’re preparing for bed, shut your curtains and turn off the lights. After DST, it will be lighter for longer. Removing any remaining daylight from your bedroom will help keep your sleep schedule intact.
- Stick to your sleep schedule. Don’t do more or stay out longer because there’s extra daylight. Keep your sleep schedule the same by going to bed and waking up at your normal time.
- Maintain healthy sleep habits. A good bedtime routine can aid your sleep schedule. Turn off all screens, including your TV and phone, at least 30 minutes before bed, avoid consuming caffeine or alcohol in the evening, and don’t exercise right before bed.
- Take naps. If you experience sleep issues because of DST, taking a short nap during the day can help. These naps should be 20 minutes or shorter—sleeping for any longer may make you feel more tired.