What Is the Best Temperature for Sleep?

By Brandon Peters, MD

It can be a common battleground for couples who sleep together: What is the best temperature for sleep? Whether you are fighting over a thermostat setting, disagree on the best bedding or sleep attire, or are tugging or throwing covers from one side of the bed to the other, the effects of the bedroom temperature may be important. It may even cause insomnia. Learn the optimal room temperature for sleep, what to do if it is too warm or too cold at night, how to sleep better if the temperature is uncomfortable in the summer or winter, and what medical conditions may make it hard to regulate body temperature at night.

The Effects of the Bedroom Environment on Sleep

First, consider what makes for an ideal bedroom environment. Beyond reserving it as a space for sleep and removing electronics, including bright screens, it is also important to consider the roles of noise, light and temperature. As a general, the bedroom should be quiet, dark, and a cool but comfortable temperature. Why might this be?

Consider how you would be sleeping if you did not have a modern home. Imagine as it was 40,000 years ago, living as a Neanderthal. Normal bodily processes, including sleep and temperature regulation, would be closely tied to the natural environment. When it becomes dark and starts to cool off, your body temperature also drops and you would get sleepy and lie down for the night. These same patterns persist in the present day, driven by genetic and environmental factors.

The body temperature reaches its lowest point about 2 hours before your normal wake time. This means if you usually wake up at 6 a.m., your minimum core body temperature will occur at 4 a.m. If you have ever stayed up through the night, you may have noticed how cold you feel at this time. Most of the time we are asleep, however. Towards morning, as the sun approaches the eastern horizon, our body temperature starts to increase, following a consistent circadian (“near day”) pattern.

The pairing of our body temperature to the temperature of the environment helps to minimize heat loss overnight. It may promote normal features of sleep, including the patterns of deep and REM sleep. But what is the best temperature for sleep?

What is the Ideal Bedroom Temperature?

Sleep experts at the National Sleep Foundation recommend that there is an ideal bedroom temperature range to promote healthy sleep. These ranges may vary somewhat based on age. Consider these recommendations:

• Babies and toddlers: 65 to 70 degrees Fahrenheit (18 to 21 degrees Celsius)

• Children and adults: 60 to 67 degrees Fahrenheit (15 to 19 degrees Celsius)

It may be best to use a smart thermostat to regulate the temperature of your home, turning down the temperature setting overnight. A degree variation from these recommendations, higher or lower, likely has little effect. Though these suggestions may be comfortable for most people, respect your body. If you feel too cool, or too warm, you may have to make some adjustments.

What If It Is Too Cold?

If you sleep in an environment that is too cold at night, your body will have to work to maintain your core body temperature at the desired level. This may provoke shivering, as the muscles of the body contract to produce warming energy. Feeling cold at night may also provoke awakenings. This may be helpful to make changes in the environment, such as pulling up covers or snuggling close to a bed partner. Unfortunately, it may also contribute to poor sleep quality and insomnia.

In extreme scenarios, such as sleeping unprotected in the woods with inadequate clothing, may provoke a serious decrease in the body temperature that can lead to hypothermia and even death due to exposure.

What If It Is Too Warm?

Almost everyone has experienced a night when their bedroom was too warm, making it hard to fall asleep. This may occur in the summer on especially hot days. What occurs when the bedroom is too warm at night?

Not surprisingly, the most common side effect of feeling too warm at night is sweating. The body regulates its temperature by increasing blood flow to the periphery (including to the hands and feet). It also promotes evaporative cooling by causing sweating. Just like during wakefulness, sweating may start in the hair of the head, armpits, and groin. If additional cooling is needed, the torso (chest, abdomen, or back) or extremities (arms and legs) may become slick with sweat.

Beyond feeling sweaty, there may be restless sleep with frequent awakenings and position changes contributing to insomnia. Attempts may be made to flip a pillow over to its cool side, to throw off covers, or to move away from a bed partner. It may be necessary to remove clothing, such as shedding warm pajamas or other sleep attire. It may help to open a window overnight, so the natural cooling of the environment can occur in the bedroom as well. In some cases, major adjustments may be necessary, including changes in the mattress or pillow (such as avoiding memory foam) to improve temperature regulation during sleep.

If the body temperature increases to a dangerous level, the effects of the resulting fever may cause serious consequences, including loss of consciousness, seizures, coma, and even death.

What About Humidity?

Beyond temperature, it is also important to consider the effects of humidity on sleep. When air is cold, or warm, there are changes in the amount of moisture that the air contains. In the winter, colder air may be more dry and this may affect the ability to breathe optimally during sleep. This may lead to nasal dryness or congestion, increasing snoring or sleep apnea, or even may make it more likely to develop upper respiratory illnesses like colds or influenza. Humidifier use, especially in a dry climate, may make it more comfortable to breathe at night and this may improve sleep. 

How to Sleep Better During Cold Weather 

What should you do if you are having difficulty sleeping due to a bedroom that is too cool? This may be more likely during cold weather during the winter months. It may also occur if you share a bedroom with someone who prefers a cooler temperature. Consider these options:

• Wear warmer pajamas (think flannel)

• Use extra blankets or an electric heated blanket

• Put heavier bedding on the bed (such as a heavy comforter or duvet)

• Turn up the thermostat

• Consider a space heater (kept away from flammable materials and with a safety timer feature to automatically turn off)

• Cuddle with a bed partner or pet

• Wear warm socks to bed

• Drink a warm beverage before bedtime (but avoid caffeine)

• Take a hot shower or bath prior to coming to bed

• In some cases, you may need to sleep in a different bedroom from someone who has a starkly different temperature preference at night.

How to Sleep Better During Warm Weather 

What if it is just too hot at night? Fortunately, there may be some helpful interventions to cool off at night when the weather gets too warm. Review these suggestions:

• Choose light, breathable sleep attire (such as cotton) or sleep naked

• Remove heavy blankets and bedding and consider using just a sheet

• Set up a circulating fan near the bed

• Use the air conditioning overnight

• Take a cool shower or bath prior to bedtime

• Leave the windows open at night

• Avoid artificial memory foam mattresses or pillows

• Consider the use of cooling devices (including pillows, sheets, pads, or even headgear)

If the unpleasant weather is due to a summer heat wave, hopefully it breaks quickly and your sleep will promptly return to normal as it does.

Is Poor Temperature Regulation a Medical Condition?

It is normal to question whether a difficulty regulating the body temperature at night is due to a medical condition. In some cases, such as an acute illness associated with a fever, it clearly is. There may be other chronic medical conditions that affect temperatures at night as well.

The most common conditions that impact the body temperature overnight are related to hormones. Thyroid problems often cause sweats or chills, correlating with hyperthyroidism or hypothyroidism, respectively. In addition, night sweats may be linked to the hormonal changes of menopause.

Sweating may occur due to the side effects of some medications. Sleep disorders such as sleep apnea can lead to frequent sweats due to the associated bursts of cortisol (stress hormone). Obesity, anxiety, and even hypoglycemia may cause sweats at night.

There are rare conditions that can cause elevated temperatures at night, including infectious diseases like tuberculosis and even some cancers. If the temperature regulation problems persist without explanation, especially in the context of other symptoms, it may be worth getting checked out. 

Conclusion

If you have difficulty sleeping comfortably at night, review whether you can make some changes to help yourself to sleep better. If you struggle with chronic insomnia, consider cognitive behavioral therapy for insomnia (CBTI). Fortunately, speaking with a board-certified sleep physician can often provide you the answers you need to sleep normally throughout the year, tolerating the normal variation of nighttime temperatures.

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Szymusiak R. “Body temperature and sleep.” Handb Clin Neurol. 2018;156:341-351. doi: 10.1016/B978-0-444-63912-7.00020-5. 

Roth T, et al. “A novel forehead temperature-regulating device for insomnia: a randomized clinical trial.” Sleep. 2018 May 1:41(5). doi: 10.1093/sleep/zsy045.

Lappharat S, et al. “Effects of Bedroom Environmental Conditions on the Severity of Obstructive Sleep Apnea.” J Clin Sleep Med. 2018 Apr 15;14(4):565-573. doi: 10.5664/jcsm.7046.

Kryger MH, et al. Principles and Practice of Sleep Medicine. ExpertConsult, 6th edition, 2017.

Optimizing the Bedroom Environment for Sleep

By Brandon Peters, MD

It may seem like a rather inconsequential thing, but you shouldn’t underestimate the importance of the bedroom environment to sleep. It may be the one thing that helps you quickly transition to rest—or the thing that keeps you tossing and turning all night in fits of insomnia.

What is the Sleep Environment?

The sleep environment is simply the space in which you attempt to sleep. It may vary as our lifestyle dictates. For example, a business trip, a prolonged flight, or a camping expedition may result in sleep environments as variable as a hotel, an airplane, or a tent. Ideally the space in which we attempt to sleep would be conducive to our efforts.

Not everyone will agree on what makes for the best features of a chosen sleep environment. This may lead to relationship problems between bed partners requiring that we attempt to find common ground. There are a handful of common variables, however, that should be acknowledged:

1. Noise

In general, it is easiest to sleep in a quiet place. Whether it is a vestige of surviving in the wilderness or for some other reason, we tend to respond to external stimuli while asleep. In other words, if we hear a noise, we will wake up. This is advantageous if a lion is trying to eat us while we sleep in a cave, but when the neighbor is blasting the radio too loud it is less desirous.

When we hear noise we may not come fully to consciousness, but we certainly will leave deeper stages of sleep. If we are trying to sleep in a noisy environment, our ability to enjoy restful deep sleep will be compromised. It is therefore best to try to keep things as quiet as possible.

2. Temperature

Most people prefer to sleep in a slightly cool environment. You may bury yourself in thick blankets, but no matter how you choose to sleep, you no doubt want to be at the right temperature. Most people should target a bedroom temperature between 60 and 67 degrees. If you wake up shivering or drenched in sweat, the temperature of your sleep environment is a problem. Why is it a problem? It woke you up! When determining the best options for your sleep environment always remember that your goal is to sleep soundly.

3. Lighting

The amount of light can impact how well you sleep. In general, it is best to sleep in darkness. You may prefer to have a nightlight (especially for safety reasons if you get up during the night). Our body’s natural circadian rhythm tends to want to follow the natural dark-light cycle. Therefore, even if you are working nights, you should probably try to keep it dark when you are trying to sleep.

4. Bedding/Mattress

There are a variety of options in how people choose to sleep and there is no one right way. Variations may relate to personal preference, cultural practices, financial opportunities, and many other factors. Some things to consider may be the use of a mattress and its character (such as size and firmness). You may prefer only a sheet or mounds of blankets or a thick comforter.

5. Preserving the Sleep Space

The bedroom can sometimes become a multipurpose room, especially if you have space constraints (such as those in college dorms). You may choose to have a television in your bedroom or even sleep with your favorite pet at your side.

The bedroom space should be a relaxing place and not a source of stress or stimulation. As part of the general guidelines for good sleep, bedrooms are for sleep and sex, not for other activities. You should not be doing work there. Various electronics (televisions, gaming systems, computers, telephones, and other gadgets) should be removed from your sleep environment. Not only will they prevent you from falling asleep, they may become disruptive at inopportune times and wake you back up.

By carefully considering the variables in your sleep environment and preserving the space to foster a good night’s sleep, you will be able to rest better and wake up ready to have a successful and productive day.

Insomnia Treatment Option: Stimulus Control

Insomnia is a prevalent sleep disorder characterized by difficulty falling asleep, staying asleep, or waking up too early. This condition can significantly impact daily functioning and overall quality of life. Among various treatment options available for insomnia, stimulus control therapy (SCT) is a highly effective behavioral intervention designed to help individuals improve their sleep patterns. This article will explore the principles of stimulus control, its implementation, and its benefits in treating insomnia.

Understanding Stimulus Control

Stimulus control therapy is based on the idea that certain stimuli in a person’s environment can become associated with sleep difficulties. These stimuli can include the bed, the bedroom, and even the act of trying to sleep itself. When a person spends too much time awake in bed or associates their sleeping environment with anxiety or frustration, it can create a cycle of insomnia.

The goal of stimulus control therapy is to re-establish a healthy relationship with sleep by modifying these associations. SCT encourages individuals to create a conducive sleep environment and develop habits that signal to their bodies that it is time to sleep. This behavioral approach is often part of a broader cognitive-behavioral therapy for insomnia (CBT-I) framework, which is considered one of the most effective treatments for chronic insomnia.

Key Principles of Stimulus Control Therapy

The implementation of stimulus control therapy involves several key principles that focus on creating a strong association between the bed and sleep. These principles are as follows:

1. Use the Bed Only for Sleep and Intimacy: One of the foundational concepts of SCT is to reserve the bed for sleep and sexual activity only. Engaging in other activities, such as watching TV, working, or eating in bed, can weaken the association between the bed and sleep. By limiting activities in bed, individuals reinforce the idea that the bed is a place for sleep, thereby promoting relaxation when they lie down.

2. Establish a Consistent Sleep Schedule: Maintaining a regular sleep-wake schedule is essential for regulating the body's internal clock. SCT encourages individuals to go to bed and wake up at the same time every day, even on weekends. Consistency helps reinforce the body’s natural sleep-wake cycle, making it easier to fall asleep and wake up feeling refreshed.

3. Get Out of Bed if Unable to Sleep: If a person cannot fall asleep within about 20 minutes, they should get out of bed and engage in a quiet, relaxing activity in another room until they feel sleepy. This practice helps to prevent negative associations with the bed and reduces frustration. It allows the individual to return to bed only when they feel drowsy, reinforcing the connection between the bed and sleep.

4. Limit Naps: While napping can be beneficial, excessive daytime sleep can disrupt the natural sleep-wake cycle and make it more challenging to fall asleep at night. SCT suggests limiting naps to 20-30 minutes and avoiding them in the late afternoon or evening to maintain sleep pressure for nighttime.

5. Create a Relaxing Pre-Sleep Routine: Establishing a calming pre-sleep routine can signal to the body that it is time to wind down. Engaging in relaxing activities, such as reading, taking a warm bath, or practicing relaxation techniques, can help prepare the mind and body for sleep.

Implementation of Stimulus Control Therapy

Implementing stimulus control therapy requires commitment and consistency. Here are steps to help individuals effectively incorporate SCT into their routine:

1. Assess Sleep Patterns: Begin by keeping a sleep diary for one to two weeks to identify sleep patterns, bedtime routines, and factors that may be contributing to insomnia. This assessment will provide valuable insights into areas for improvement.

2. Set a Regular Sleep Schedule: Determine a target bedtime and wake-up time that allows for adequate sleep duration. Aim for 7-9 hours of sleep each night and be consistent with this schedule.

3. Create a Comfortable Sleep Environment: Ensure that the bedroom is conducive to sleep. This includes a comfortable mattress and pillows, optimal room temperature, and minimal noise and light disturbances. Consider using blackout curtains, earplugs, or white noise machines if needed.

4. Practice Relaxation Techniques: Incorporate relaxation techniques into the pre-sleep routine. Techniques such as deep breathing, progressive muscle relaxation, or meditation can help calm the mind and prepare the body for sleep.

5. Monitor Progress: After implementing stimulus control therapy, continue to keep a sleep diary to track improvements in sleep patterns and any remaining challenges. Adjust the approach as needed and remain patient, as behavioral changes may take time to yield results.

Benefits of Stimulus Control Therapy

Stimulus control therapy offers numerous benefits for individuals struggling with insomnia:

1. Improved Sleep Quality: By reinforcing healthy sleep associations, SCT can lead to more restful and uninterrupted sleep. Individuals often report feeling more refreshed and energized upon waking.

2. Reduction in Sleep Anxiety: By changing negative associations with sleep and the bedroom, individuals can experience reduced anxiety related to falling asleep. This newfound relaxation can further facilitate better sleep quality.

3. Behavioral Change: SCT promotes long-term behavioral changes that contribute to better sleep hygiene. These changes can help individuals develop healthier habits surrounding sleep, enhancing overall well-being.

4. Minimal Side Effects: Unlike pharmacological treatments for insomnia, stimulus control therapy is a non-invasive and natural approach. It does not come with the risk of dependency or adverse side effects commonly associated with sleep medications.

5. Empowerment and Self-Efficacy: SCT encourages individuals to take control of their sleep patterns and make conscious choices to promote better sleep. This empowerment can foster a greater sense of self-efficacy and improve overall mental health.

Conclusion

Stimulus control therapy is a valuable treatment option for individuals struggling with insomnia. By focusing on the environmental and behavioral factors that influence sleep, SCT can help individuals re-establish a healthy relationship with sleep and improve their overall sleep quality. With commitment, consistency, and a willingness to change, those suffering from insomnia can experience significant benefits from this behavioral approach. As part of a comprehensive treatment plan that may include cognitive-behavioral strategies and relaxation techniques, stimulus control therapy offers a pathway to restful nights and rejuvenated days. If insomnia persists, consulting a healthcare professional is advisable to explore additional treatment options tailored to individual needs.

This article was created using OpenAI’s ChatGPT on October 3, 2024 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.

Unraveling the Mystery: Why Does Your Heart Rate Spike During Sleep?

Sleep is a crucial aspect of our daily lives, allowing our bodies to rest, recover, and rejuvenate. However, for some individuals, the tranquility of sleep is disrupted by sudden spikes in heart rate. This phenomenon, known as sleep-related tachycardia, can be both bewildering and concerning. In this article, we will delve into the underlying reasons behind these nocturnal heart rate fluctuations and shed light on the potential causes and remedies.

The Basics of Heart Rate and Sleep

Before we delve into the reasons for heart rate spikes during sleep, it's essential to understand the fundamentals of heart rate regulation and the sleep cycle. The heart rate is a measure of how many times your heart beats per minute. During sleep, our body undergoes several stages, including light sleep, deep sleep, and REM (rapid eye movement) sleep. Each stage has a distinct impact on heart rate and other bodily functions.

Normal Heart Rate Variations During Sleep

Fluctuations in heart rate during sleep are normal and can be influenced by various factors, such as age, overall health, and physical fitness. Typically, the heart rate gradually decreases as you transition from wakefulness to deep sleep. During REM sleep, when vivid dreaming occurs, heart rate variability is higher, reflecting increased brain activity.

Causes of Heart Rate Spikes During Sleep

Sleep Apnea: One common cause of sleep-related tachycardia is obstructive sleep apnea (OSA). In this condition, the airway becomes partially or completely blocked during sleep, leading to breathing pauses and subsequent drops in oxygen levels. The body responds by increasing the heart rate to compensate for the reduced oxygen supply as the brainstem triggers a release of cortisol to trigger an awakening and restored breathing.

Nightmares and Sleep Disorders: Intense nightmares, night terrors, or other sleep disorders can trigger a sudden spike in heart rate. These conditions can activate the body's "fight or flight" response, part of the autonomic nervous system, causing an adrenaline rush and increased heart rate.

Anxiety and Stress: Persistent anxiety and stress can disrupt sleep patterns and lead to an increased heart rate during sleep. The mind-body connection plays a significant role in regulating heart rate, and heightened emotional states can result in physiological changes, including elevated heart rate.

Medications and Stimulants: Certain medications, such as beta-blockers or stimulants like caffeine or nicotine, can interfere with sleep and cause an elevated heart rate during the night.

Potential Health Implications

While occasional heart rate spikes during sleep might not be cause for alarm, persistent or severe tachycardia (with a rate of 100 or more beats per minute) can be indicative of underlying health issues. Individuals experiencing recurrent episodes of elevated heart rate during sleep should consider consulting a healthcare professional to rule out any underlying conditions or identify appropriate treatment options.

Tips for Managing Sleep-Related Tachycardia

1. Maintain a Consistent Sleep Schedule: Establishing a regular sleep routine helps promote better sleep quality and reduces the likelihood of heart rate fluctuations during sleep.

2. Create a Relaxing Sleep Environment: Ensure your sleep environment is conducive to relaxation, free from distractions, and kept at a comfortable temperature. Consider the role of light, noise, and other environmental disruptions (including a bed partner or pets).

3. Practice Stress Reduction Techniques: Incorporating stress reduction techniques like meditation, deep breathing exercises, or engaging in a calming bedtime routine can help lower overall anxiety levels and promote better sleep.

4. Avoid Substances: Limit the intake of substances such as caffeine, nicotine, and alcohol, as they can interfere with sleep quality and contribute to heart rate irregularities.

Conclusion

While occasional spikes in heart rate during sleep can be a normal response to various factors, persistent or severe tachycardia during sleep should not be ignored. By understanding the potential causes and adopting healthy sleep habits, individuals can take proactive steps towards managing sleep-related heart rate fluctuations. If concerns persist or worsen, consulting a healthcare professional is advisable to ensure optimal sleep and overall well-being.

This article was created using OpenAI’s ChatGPT on July 8, 2023 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.