New research suggests that exposure to natural light during the day could improve sleep, even on cloudy winter days.

A recent study found that college students who fell asleep later at night woke up later in the morning during the winter months. Researchers suggest that the lack of natural light during the day could lead to sleep problems at night. The results indicate that exposure to natural light during the day – particularly in the morning and midday – could improve sleep, even on cloudy days in winter. Seasonal affective disorder (SAD) might play a role, but more research is still needed. To get a good night’s rest, spend time outdoors during the day, exercise regularly, and maintain a regular sleep schedule. During the winter months, when the days are shorter and darker, many people spend less time outdoors and don’t get as much natural light. It can impact mood, energy, and sleep.

Previous studies indicate that exposure to natural sunlight for at least 30 minutes has a significant impact on the body’s internal clock, promoting more restful sleep. A recent study has revealed some interesting insights into our body’s sleep patterns and demonstrates the value of going out during the day, even on cloudy days. The findings, recently published in the Journal of Pineal Research, show that not having enough natural light during the day leads to problems when it comes to getting quality sleep at night. Exposure to daylight is really essential for maintaining a healthy circadian system and subsequent sleep hygiene.

How sleep patterns change with the seasons

For the study, 500 students at the University of Washington in Seattle wore wrist-mounted monitors that allowed researchers to monitor their sleep patterns throughout all four seasons.
The data shows that the students got roughly the same total amount of sleep each night, whether in winter or summer.

Yet during the winter months, students who fell asleep later at night woke up later in the morning, a time of day in the region with less daylight and cloudy weather. On average, they fell asleep 35 minutes later and woke up 27 minutes later on winter school days compared to summer school days. Since there is less daylight in the winter, the students’ sleeping and waking patterns surprised the researchers. For your information, Seattle gets about 16 hours of sunshine at the summer solstice and just over 8 hours of sunshine at the winter solstice.

According to the researchers, students go to bed late and sleep in because they don’t get enough natural light during the winter months.

Exposure to natural light during the day advances the body’s biological clock which times sleep. This makes it easier to fall asleep at a reasonable time and wake up early in the morning. Of course, it’s important to note that this study may be limited by location, with Seattle being notoriously cloudy. Further studies in different geographic regions are needed to confirm whether exposure to natural light can actually promote sleep.

How Daylight Affects Circadian Rhythms

Both daylight and evening light affect the timing of your circadian cycles. While exposure to daylight promotes restful sleep at night, evening light can delay your internal clock and interfere with your ability to fall asleep and get good quality sleep. Normally, light is a wake-up call and evening light can suppress melatonin and impair sleep.

According to the University of Washington study, each additional hour of daylight was linked to improved circadian rhythms. The authors also noted that bright midday light was more effective at improving sleep than morning light. In this study, the most interesting thing is that, in addition to sunrise and sunset times, the authors noted that noonday light, of high intensity, plays a very powerful role and is correlated with the delay of circadian rhythms. The researchers also suggest that daily exposure to daylight is essential to prevent this delayed phase of the circadian clock and therefore the circadian disruption that is typically exacerbated in high latitude winters. »

Does seasonal affective disorder affect sleep?

Seasonal affective disorder (SAD), or major depressive disorder (MDD) with a seasonal pattern, usually occurs during the winter months when sunlight is less. In some cases, people may experience SAD during the summer months.

Symptoms of SAD can include:

difficulty sleeping
weight gain
social withdrawal

SAD is thought to be the result of light-induced circadian dysregulation, which can lead to emotional changes and mood swings. However, researchers have not yet determined whether SAD symptoms could be alleviated by exposure to natural light.

Tips for better sleep

Whether or not you’re having trouble sleeping due to SAD or have trouble sleeping in general, there are proven ways to improve sleep hygiene and get a good night’s rest anytime you want. the year.

Be vertical during the day

Since midday light can help adjust the circadian rhythm, the more you exaggerate the gap between sleep and wakefulness by being more upright or upright during the day, the better horizontal you will be at night. Walking and other forms of physical activity, ideally outdoors, and not lying down immediately after eating can also help you sleep better.

Maintain a consistent schedule

Going to bed at the same time every night and waking up at the same time in the morning can help train your body’s sleep-wake cycle. Sleep likes regularity, so try to keep regular schedules, roughly the same on weekends and weekdays.

Look for signs of fatigue and low mood

Seasonal depression is known to be more prevalent in northern and southern latitudes and can affect your mood and disrupt your sleep. This means it can be a good idea to self-monitor for symptoms of depression, which can manifest as fatigue, low energy, or lack of excitement or joy. If you have depression-like symptoms and have trouble sleeping, you can see your doctor or a mental health professional for further advice.

In summary

A recent study shows that students who fall asleep later at night wake up later in the morning during the winter months due to a lack of exposure to natural light during the day. The results suggest that getting more exposure to natural light, especially in the morning and midday, is essential for maintaining a healthy circadian clock and getting a good night’s sleep. Although seasonal affective disorder (SAD) can also affect sleep during the winter months, the current study did not consider SAD in its analysis. To improve your sleep habits in winter, experts recommend spending more time outdoors, being physically active, and following a regular sleep routine. If you suffer from depression and insomnia, do not hesitate to consult your doctor about your treatment options.

* criptom strives to transmit health knowledge in a language accessible to all. In NO CASE, the information given can not replace the opinion of a health professional.