Weekend Sleep-Ins: Why Do We Need Them?

Sleeping in on the weekends is a common occurrence, especially for teenagers and young adults. While it may be tempting to blame our body clocks for this, the real culprit is often our exposure to artificial light in the evenings, which suppresses the synthesis of the sleep-facilitating hormone melatonin. This disrupts our body clocks and accumulates sleep debt, resulting in longer sleep durations during the weekends as we try to pay off this debt. Additionally, our need for sleep declines with age, so teenagers require more sleep than middle-aged adults. Other factors such as individual differences in body clocks, sensitivity to evening light, and lifestyle habits also contribute to variations in weekend sleep patterns. To reduce social jet lag, it is recommended to make time for sleep during the week, minimize exposure to artificial light in the evenings, and ensure exposure to natural light in the mornings.

The impact of artificial light on sleep

Artificial light has a significant impact on sleep, influencing circadian rhythm, melatonin production, and sleep cycles. Circadian rhythm is a 24-hour internal clock that regulates various bodily processes, including sleep. This rhythm is controlled by a small part of the brain, known as the circadian pacemaker, which is highly sensitive to light exposure.

The human body has evolved to sleep when it is dark and be awake during sunlight. However, with the advent of artificial lighting, our exposure to light has increased dramatically, especially during the evening and night. This excess artificial light can cause a misalignment between our internal clock and the natural day-night schedule, leading to disrupted sleep and other health issues.

One of the key ways artificial light impacts sleep is by affecting melatonin production. Melatonin is a hormone that helps regulate sleep, and its production is closely tied to light exposure. When it is dark, the body produces more melatonin, promoting sleepiness. However, exposure to artificial light, especially blue light emitted by electronic devices, can slow down or halt melatonin production, making it harder to fall asleep.

Additionally, artificial light exposure at night can hinder transitions between sleep cycles, reducing sleep quality. It can cause repeated awakenings and interrupt the deeper, more restorative stages of sleep. This can lead to excessive daytime sleepiness and negatively impact overall health, including the immune system, mental health, and heart health.

The effects of artificial light on sleep are not just limited to the evening and night. Exposure to artificial light during the day can also impact sleep. For example, spending too much time indoors under artificial lighting can reduce exposure to natural daylight, which is important for regulating sleep.

To mitigate the impact of artificial light on sleep, it is recommended to reduce exposure to artificial lighting, especially before bedtime. This can be achieved by dimming the lights, using low-power lamps, and minimising screen time a few hours before bed. Creating a dark bedroom environment with blackout curtains or eye masks can also help improve sleep quality.

Sleep disorders

If you find yourself sleeping all day on weekends, it could be a sign of a sleep disorder. Sleep disorders can cause hypersomnia, or excessive sleepiness, which is characterised by symptoms such as feeling unusually tired all the time, needing to nap during the day, and experiencing difficulty thinking and making decisions.

There are several types of sleep disorders that can contribute to hypersomnia, including:

• Sleep apnea: The person's breathing stops or is reduced during sleep, causing them to rouse slightly and gasp for air.
• Insomnia: Difficulty falling or staying asleep.
• Restless legs syndrome: Irritating sensations in the legs that compel the person to move their legs or get out of bed.
• Sleep walking: Walking around while still asleep, more common in children.
• Narcolepsy: A rare disorder characterised by involuntary napping, sleep paralysis, vivid hallucinations, and muscle weakness during strong emotions.
• Idiopathic hypersomnia: Excessive night-time sleeping and daytime napping without the paralysis or hallucinations of narcolepsy.

If you suspect you may have a sleep disorder, it is important to seek advice from a doctor or sleep disorder clinic. They can help identify any underlying causes and provide treatment options.

In addition to sleep disorders, there are other factors that can contribute to excessive sleepiness. These include inadequate sleep due to long working hours, shift work, family demands, or social life. Environmental factors such as noise or temperature can also affect sleep quality. Mental health issues like anxiety and depression can impact sleep, as can certain medications and medical conditions.

To improve sleep quality, it is recommended to make lifestyle adjustments such as maintaining a regular sleep schedule, creating a relaxing bedtime routine, and reducing exposure to light from electronic devices before bed. It is also important to address any underlying health or mental health issues that may be disrupting your sleep.

While it may be tempting to sleep in on the weekends, this can contribute to what is known as "social jet lag". This occurs when there is a significant difference in sleep timing between the workweek and the weekend, causing a disruption to your body's natural sleep-wake cycle. To reduce social jet lag, try to make more time for sleep during the week, limit exposure to artificial light in the evenings, and ensure you get some natural light in the morning.

The effects of age on sleep

Ageing affects sleep in several ways. Firstly, older adults may experience changes in the quality and duration of their sleep due to changes in the body's internal clock, known as the circadian rhythm. This internal clock is controlled by the suprachiasmatic nucleus (SCN), which is located in the hypothalamus and regulates 24-hour daily cycles, including when people feel sleepy or alert. As the SCN deteriorates with age, it can disrupt circadian rhythms, leading to a shift in sleep schedules, with people feeling tired earlier in the afternoon and waking up earlier in the morning.

Additionally, older adults may experience more fragmented sleep and become more sensitive to external stimuli like light or sound, causing them to wake up more easily. This increased sleep fragmentation may be related to changes in hormone production, such as decreased melatonin secretion, which normally promotes sleep. Health issues such as obesity, insomnia, cognitive impairment, anxiety, and Alzheimer's disease can also contribute to sleep disturbances in older adults.

Furthermore, lifestyle changes that come with ageing can impact sleep. For example, retirement can lead to a less structured sleep-wake schedule, and social isolation can increase stress and anxiety, affecting sleep quality. Medical conditions and medications can also interfere with sleep, as many older adults take multiple medications that may impact sleep.

While older adults may need the same amount of sleep as younger individuals (7-9 hours for adults 18-64 years old and 7-8 hours for those 65 and older), the structure of their sleep changes. They experience more frequent awakenings during the night and spend less time in deep sleep (slow-wave sleep). This can result in non-restorative sleep and excessive daytime sleepiness, which is not a normal part of ageing.

To improve sleep quality, older adults can regulate their sleep and waking times, avoid late naps, improve their sleeping environment, and reduce screen time before bed. Exercise is also beneficial, as it helps older adults fall asleep faster and improves sleep quality.

The impact of lifestyle on sleep

Lifestyle can have a significant impact on sleep quality and duration. This includes factors such as work schedules, social life, diet, exercise habits, and exposure to artificial light. Here are some ways in which lifestyle can influence sleep:

• Work Schedules: Those who work long hours or irregular shifts often experience sleep disturbances. This is especially true for shift workers, who may struggle to align their sleep schedules with their ever-changing work hours. As a result, they may accumulate sleep debt, leading to excessive sleep during their days off.
• Social Life and Lifestyle Choices: A busy social life or lifestyle choices can impact sleep. Staying out late, consuming alcohol, or using electronic devices before bed can disrupt sleep patterns and reduce overall sleep duration. Socializing and relaxing often take precedence over adhering to a strict sleep schedule, contributing to what is known as "social jet lag."
• Diet and Exercise: Diet and exercise play a crucial role in maintaining healthy sleep patterns. Consuming a balanced diet, rich in vegetables and whole foods, can improve energy levels and promote better sleep. On the other hand, excessive alcohol consumption can disrupt sleep patterns and contribute to non-restorative sleep. Regular exercise, even low-intensity activities like walking or yoga, can help improve sleep quality and energy levels.
• Exposure to Artificial Light: Artificial light, particularly in the evening, can disrupt the body's natural sleep-wake cycle. It suppresses the production of melatonin, a hormone that facilitates sleep. By staying awake past sunset and exposing ourselves to artificial light, we inadvertently disrupt our body clocks, making it challenging to wake up early and potentially leading to excessive sleep on weekends.
• Age and Individual Differences: Age plays a role in sleep duration, with teenagers requiring more sleep (up to 9 hours or more) compared to middle-aged adults (7 to 8 hours). Additionally, individual differences in biological clocks and sensitivity to evening light contribute to variations in weekend sleep habits. Some individuals have faster or slower body clocks, resulting in delayed sleep during the week and longer sleep on weekends.

It's important to note that while lifestyle choices can impact sleep, consistent oversleeping may also be a sign of underlying health issues. Hypersomnia, or excessive sleepiness, can be caused by sleep disorders, mental health disorders, or other medical conditions. If you are concerned about your sleep habits, it is advisable to consult a healthcare professional for personalized advice and guidance.

How to improve sleep quality

If you find yourself sleeping all day on weekends, it could be a sign that you are not getting enough quality sleep during the week. Here are some tips to improve your sleep quality:

Improve your sleep environment

Make your bedroom a cool, quiet, and dark space. Minimise noise, light, and artificial light from devices such as alarm clocks. You can also use blackout curtains, earplugs, or a sleep mask to create a comfortable environment.

Stick to a sleep schedule

Go to bed and wake up at the same time every day, even on weekends. This helps to regulate your body's circadian rhythm and improve long-term sleep quality.

Limit exposure to blue light in the evening

Blue light from electronic devices like smartphones and computers can negatively impact your sleep by reducing levels of melatonin, a hormone that helps you relax and sleep. Try to avoid screens at least one to two hours before bedtime.

Avoid caffeine and alcohol late in the day

Caffeine and alcohol can disrupt your sleep. Avoid consuming caffeinated beverages at least eight hours before bedtime, and do not drink alcohol close to bedtime.

Optimise your diet

Try not to eat large meals or high-carb foods late in the evening. Eating a big dinner close to bedtime can disrupt your sleep. Instead, opt for a light snack if you need something to eat.

Exercise regularly, but not too close to bedtime

Regular exercise can improve your sleep, but intense exercise close to bedtime may hinder your body's ability to settle down for sleep. Try to exercise earlier in the day and leave a few hours between your workout and bedtime.

Practice relaxation techniques

Practising relaxation techniques such as mindfulness, meditation, deep breathing, or reading a book before bed can improve your sleep quality. These techniques can help you feel more relaxed and calm, making it easier to fall asleep.

Frequently asked questions