11 Quick Science-backed Sleep Improvement Tips

Sleep disturbances are as common as wind in the air. Some studies^[1] report over 40% of the population having significant sleep disturbances. Some countries show a typical average of 20-25%. High school children^[2] (10.4%) and older adults^[3] (up to 45%) also show a high prevalence of poor sleep. The risk of death from cardiovascular diseases^[4] is 29% higher in those who get less sleep and have sleep disturbances. And, there is a high risk of mental health problems^[5] and poor attention, memory, decision-making^[6], reasoning, speed, and accuracy^[7] as sleep gets worse. These estimates say about 1.5-2 billion people (about 1 in 3, 15+ years of age) in the world have an unhealthy sleeping pattern with a significant risk of health problems.

The reasons for little and bad sleep are many – conditions like sleep apnea and chronic pain, mental health problems, environmental disturbances like construction sounds and brightness, stress, long working hours, lifestyle choices like alcohol, binge-watching, smoking, etc. Sleep deprivation is fairly normalized in a fast society, it’s a chronic problem^[8].

The drop in sleep quality due to these problems is not an unsolved problem. Many everyday actions can help you fall asleep faster with more restful and deep sleep that restores the body and does some damage control. These “behavioral aids” help with common sleep problems like not being able to fall asleep after shutting eyes, finding it hard to return to sleep after a disturbance, and sleep getting interrupted due to distractions, overthinking, noise, etc.

1. White noise and relaxing sounds

White noise, a form of continuous fuzzy sound, is a popular sleep aid. People use speakers or headphones on low volume and listen to white noise to fall asleep. It is theorized that white noise blocks external distracting sounds and masks them as if they don’t exist. When the brain gets habituated to the white noise, the noise itself drowns out after it blocks out other intrusive sounds. The research^[9]is not very convincing because there are too many factors to assess the conditions for good or bad sleep, but people stand by it. This technique seems more useful in areas with high city noise as per a study^[10]. Researchers found white noise helped people in New York fall asleep faster and reduce wakefulness moments during sleep. The trick may be to use white noise for a short duration (20-45 minutes) to push the body to sleep instead of using it all night long.

Other consistent sounds like nature ASMR sounds^[11] like waves, burning wood, rainforest sounds, nature sounds with binaural beats^[12], only binaural beats^[13] (5-30 Hz) play the same role as white noise, with the added benefit of relaxation.

Use cases: Reduce sleep disturbances through city sounds, fall asleep faster.

2. Sounds of your choice

Humans typically consider something as annoying or helpful based on whether they choose it. The sound of an AC vent can be a disturbing sound at night but the choice to listen to a podcast or a horror story for sleeping can be soothing, simply because the latter was chosen and the former was not. Researchers point out this choice is important^[14] in determining if a certain type of sound induces or disturbs sleep. Many today choose to listen to audio narrations in the form of podcasts, stories, or guided therapy to fall asleep. Since they are chosen, these tend to help them fall asleep. This is the reason sleep-audio channels on YouTube are popular^[15] – listeners are engaged in something they relax to and the audio content helps them block out sounds and intrusive thoughts. And this is within their control and they get to choose what interests them.

3. Eye masks & Earplugs

Sleep masks (masks that cover only the eyes) and earplugs help many people sleep soundly in noisy/disturbing environments by blocking ambient light and sound^[16]. They also reduce the impact of sudden bright lights and loud sounds, which could zap the brain into wakefulness. Sleep masks and earplugs are likely to improve the quality and quantity of deep sleep by shielding the body from ambient light/sound, which may force the brain to enter a wakeful state. This is how morning light helps the body end its sleep cycle. Another factor is the release of melatonin. Outdoor light suppresses melatonin release, a compound that triggers drowsiness^[17] and is essential for quick sleep onset. Sleep masks can prevent this suppression, and let melatonin do its thing.

Deep sleep, also called slow-wave sleep, is when the body is most rested. An additional benefit^[18] of using sleep masks is that the improved deep sleep helps the brain encode episodic memories better (conversion of short-term memories to long-term memory for facts and events) and improves alertness the next day.

Use cases: Improve deep sleep, make it easier to fall asleep and return to sleep, sleeping after night-shift work, sleeping in noisy environments.

4. Muscle relaxation and relaxation visualization

A core feature of sleep disturbances is that the body is too aroused to fall asleep naturally. And if it isn’t aroused by default, modern lifestyles keep the arousal high through stress, late-night work, screen time, late-night caffeine, etc. So, a popular non-pharmacological treatment for insomnia has been reducing the body’s arousal^[19]. This is done in 2 common ways: Muscle relaxation using techniques like progressive muscle relaxation and stretching, or relaxation visualizations where a person visualizes themselves relaxing and sinking into the bed and zoning out. Visualizations tend to work better^[20], but muscle relaxation^[21] is reliable as it becomes a habit through repetition.

Use cases: Reduce body’s night-time arousal, reduce time to fall asleep

5. Sleep playlists

One of music’s functions is to relax and induce a positive mood, which people use for sleep. As children, we hear lullabies, and as adults, we often use sleep songs. Music helps us sleep through 3 mechanisms: It relaxes the body^[22], it suppresses worry and anxious thoughts^[23], and it drowns out distracting noises from the environment^[24]. A study analyzed^[25] the sleep playlists made on Spotify. A total selection of 225,000+ songs. They found some common features – the sleep music is slower and softer, tends to be instrumental, and acoustic. But, their study found high variation in what people use. A lot of sleep playlists have high-arousal pop and rock music, sometimes even metal and synthwave. Music is a special case of stimulation – sad songs can be uplifting and relaxing, high-energy songs can relax, etc. The listener’s comfort zone matters, and if it relaxes, it helps.

Use cases: Pre-sleep relaxation, preventing intrusive thoughts while falling asleep

6. Essential oils

Essential oils – oils made from plant/flower extracts that carry the “essence” of that plant/flower – are a popular sleep aid. Research suggests^[26] essential oils – most typically lavender oils – induce sleep in those with mild sleep disturbances.

Use cases: Increase drowsiness

7. Bed deconditioning

The easiest way to prepare for sleep is to use the bed only for sleeping. When the bed is used for work and eating, the brain associates the bed with wakefulness via a process called classical conditioning. Over time, frequent non-sleep bed usage makes the bed trigger 2 conflicting signals: wakefulness & sleepiness, which puts people into a tired and sleepy but awake mode. Work and eat elsewhere, not the bed. Ideally, the bed should trigger only rest and sleeping.

Use case: Improving restful sleep

8. Weighted blankets

Weighted blankets are a great choice if you have insomnia and related psychological disturbances like depression, attention deficit hyperactivity disorder, and anxiety. According to a study^[27], weighted blankets (as opposed to light blankets) showed dramatic improvements in the quality of sleep and daytime activity after just 4 weeks. Weighted blankets can be an effective way to reduce the severity of insomnia and reduce daytime lethargy. The study estimates that 6-8 kg blankets help improve sleep. For reference, a single 120 GSM duvet is about 1 to 1.1 kg, and a 4-inch thick double is close to 2.5 kg.

Use cases: Improving overall sleep and symptoms of anxiety & depression

9. Warming feet with socks or warm water

Some people love socks, some don’t. Socks cover 2 of our appendages (feet) that play a role in regulating body temperature. When our body transitions into sleep, the core temperature of the body begins to fall and reaches its all-time low in about 4 hours. Melatonin, the sleep hormone, signals heat loss that makes us drowsy. When heat exits the body, a cascade of biological reactions occurs that initiate sleep. Lowering body temperature can trick the brain into beginning sleep processes.

Because heat loss is easy from the hands and feet, the sock hack works remarkably. But since socks get warm, removing socks just at the moment of sleep can also work for those who find them too warm. In a process called vasodilation^[28], blood vessels dilate (expand) and it is easy for heat to exit the body. This lowers the core temperature. Socks (and other warming techniques) warm the feet which increases vasodilation. The vasodilation triggers heat loss, which artificially triggers the brain to initiate sleep.

Use cases: Pre-sleep preparation to fall asleep quickly

10. Pre-sleep baths

Having a warm water bath before sleeping has a similar effect as vasodilation. Right after bathing, the body begins to cool down, which can make us drowsy. Research shows that a short (upto 10 min) warm water bath (40ish degrees) 1 to 2 hours^[29] before sleep can reduce the time needed to sleep, induce deeper sleep, reduce wakefulness, and overall enhance sound sleep.

Use cases: Improve overall sleep quality

11. Avoiding caffeine 6+ hours before bedtime

Caffeine molecules block out adenosine, a neurotransmitter that tells the brain to slow down and get drowsy. Because of this blocking, the brain becomes more active, making us alert. Adenosine is necessary for feeling rested and caffeine delays sleep onset, even when you are tired. Here’s what we know from research^[30]. Caffeine stays in the body for a long time – it reaches 1/2 the volume (its half-life) in 4-6 hours and 1/5th the volume in 16 hours. Studies also typically use high doses of caffeine (2-5 brews worth) at a time to measure its effects, so it is reasonable to have milder coffee and not disrupt sleep if it is consumed 6+ hours before bedtime. For most people working a 9-5 job, mild coffee early evening is reasonable.

Use cases: Manage caffeine intake to not disrupt sleep

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