Beyond supplements, the sleepmaxxing world has produced a range of physical interventions, devices, and environmental modifications all aimed at improving sleep. Some of these have a solid evidence base. Some have none at all. And at least one carries a genuine risk that receives far too little attention. As a surgeon who spends a significant part of my clinical practice investigating and treating disorders of the upper airway during sleep, I have strong feelings about that last category.
I want to go through each of these in turn, with what the evidence actually shows, some honest uncertainty about what we do not yet know, and, where it matters, a clear clinical view on safety.
Mouth Taping
Mouth taping involves applying a small strip of tape to the lips before sleep to encourage nasal breathing. The claim is that nasal breathing reduces snoring, improves oxygenation, and leads to deeper, more restorative sleep. It has become one of the most widely discussed physical interventions in sleepmaxxing communities, and it is not entirely without logic.
Nasal breathing does have advantages over mouth breathing during sleep. The nose warms, humidifies, and filters inspired air. It also produces nitric oxide in the nasal sinuses, which has vasodilatory effects and may play a role in oxygen delivery. Some people genuinely do breathe through their mouths due to nasal obstruction, and addressing that obstruction is a legitimate clinical goal.
The problem with mouth taping is not the goal of nasal breathing. It is that taping the mouth shut before bed without knowing whether your airway is working properly is a bit like locking the fire escape before you know whether the building is safe.
Obstructive sleep apnoea occurs when the upper airway partially or completely collapses during sleep. In mild to moderate cases, this might happen dozens of times per night. In severe cases, hundreds of times. During an obstructive event, the body attempts to breathe against a closed or nearly closed airway, generating increasing respiratory effort until an arousal (a brief awakening) opens things up again. If the mouth is also sealed, the individual has fewer options available during an obstructive event. The American Academy of Sleep Medicine has explicitly warned against mouth taping in people with obstructive sleep apnoea.
The critical clinical issue is that the majority of people with obstructive sleep apnoea in the UK remain undiagnosed. Estimates suggest the figure may be well over half of all people with clinically significant OSA. The early symptom profile of OSA is not always the dramatic witnessed apnoeas and theatrical snoring of textbook descriptions. It is often simply persistent, unexplained fatigue on waking despite apparently adequate sleep. People with this pattern are precisely the people who are drawn to sleepmaxxing interventions. And snoring, one of the most common reasons people seek out mouth tape in the first place, is one of the cardinal symptoms of obstructive sleep apnoea.
There is also the straightforward practical question: what happens if your nose blocks? What if you feel nauseous? What if you vomit during the night? These are not common events, but they are real risks that become more dangerous if the mouth is sealed. Soft tissue irritation and damage to the lips have also been reported with some tape products.
My own position, having seen what happens to people with undiagnosed OSA who delay proper assessment, is this: if you want to try mouth taping and you snore, please discuss it with your GP or a sleep specialist first. If you have had a proper sleep study, do not snore significantly, breathe comfortably through your nose when awake, and simply want to encourage nasal breathing habit, a partial mouth tape (one that allows some airflow if the nose becomes blocked) is a more cautious approach than a fully sealed mouth. If you use nasal pillow CPAP and you have been told by your sleep clinic to use mouth tape to prevent air escaping, that is a different clinical context, with professional oversight. That is not the same as self-administering tape on the recommendation of a social media influencer.
Nostril Expanders and Nasal Dilator Strips
Nasal dilator strips, sometimes also called nostril expanders, are adhesive strips applied externally across the nose to hold the nasal sidewalls open. The most familiar brand is Breathe Right, and similar products have been around for decades.
These devices make genuine sense for a specific anatomical problem: lateral nasal wall collapse, also called alar collapse. In this condition, the cartilaginous sidewalls of the nose collapse inward during inspiration, restricting airflow. The dilator strip effectively simulates what ear, nose and throat surgeons call Cottle's manoeuvre, where a finger placed on the cheek and pulled laterally opens the nasal valve and relieves obstruction. If your particular problem is alar collapse, a nasal dilator strip may genuinely help.
Nasal dilator strips work well for alar (lateral wall) collapse. They do nothing for the more common causes of nasal obstruction: a deviated septum, enlarged turbinates, nasal polyps, or allergic congestion. Using them for the wrong indication means you will notice no benefit.
The difficulty is that most people with chronic nasal obstruction have one or more of these other causes: a deviated nasal septum, enlarged inferior turbinates (the fleshy structures that regulate airflow and humidify the nose), nasal polyps, or allergic rhinitis. A nasal dilator strip does nothing for any of these conditions. If your nose is congested because of inflammation, swelling, or a structural deviation, holding the sidewall open externally will not create meaningful additional airflow.
Nasal dilator strips may marginally reduce snoring in people without significant sleep-disordered breathing, by reducing the resistance of inspiration slightly. The evidence for this is modest and the effect size small. As with most of these interventions, they are safest when used with some understanding of what is actually causing your nasal problem. If you have never been assessed for nasal obstruction and you find that dilator strips make a significant difference to your breathing and your sleep, that is actually useful information: it suggests alar collapse may be a meaningful component, and it is worth telling a clinician.
Red Light Therapy
Red light therapy for sleep involves using low-intensity red or near-infrared wavelength light before bed, with the claim that it promotes the body's natural sleep-wake cycle and improves melatonin production. The theoretical basis is that unlike blue and white light, red wavelengths do not suppress melatonin secretion and may even have stimulatory effects on mitochondrial function.
I want to address a common claim that gets tangled up in this discussion. The idea that blue light specifically, from screens and artificial lighting, is uniquely harmful to sleep was for many years presented as settled science. The reality is more nuanced. Blue light wavelengths do suppress melatonin secretion through their effect on intrinsically photosensitive retinal ganglion cells. But the overall intensity of light exposure matters at least as much as its wavelength. Red light is less stimulating partly because it is typically dimmer. A bright red light would still disrupt sleep.
The published evidence for red light as a positive sleep intervention is very limited. A handful of small studies in athletes have shown some improvements in sleep quality and melatonin levels, but these involve quite specific protocols, specific wavelengths, and specific populations. No well-powered randomised controlled trial has demonstrated that commercial red light therapy devices improve sleep in the general adult population. The devices available on the consumer market make claims that considerably exceed the evidence.
My view is that if you want to use lower-intensity, warmer-toned lighting in the evenings, that is a sensible environmental modification with some biological rationale. A standard lamp with a warm-toned bulb in the evening is probably doing much the same job at a fraction of the cost. The specific claim that red light has unique therapeutic properties for sleep, beyond simply being dimmer and less stimulating than white or blue-white light, is not yet supported by the clinical evidence.
Cooling Mattress Pads
Products such as the Chilipad, Eight Sleep, and similar systems use water or air circulation through the mattress to actively cool the sleeping surface. They are marketed as maintaining the optimal sleep temperature throughout the night and are positioned as one of the more serious biohacking tools available for sleep. Some cost well over two thousand pounds.
The underlying biology here is genuine. Core body temperature needs to fall by approximately one to two degrees Celsius to initiate sleep. The body achieves this partly by dissipating heat through the skin, which is why a cool environment facilitates sleep and a hot environment disrupts it. Research consistently shows that sleeping in a room that is too warm reduces total sleep time, increases night waking, and reduces deep sleep. A 2023 systematic review of ambient heat and sleep found that higher indoor temperatures were generally associated with degraded sleep quality and quantity, with effects most pronounced during hot months and in vulnerable populations such as the elderly [1].
A cool bedroom is well evidenced. The question of whether an expensive active cooling mattress does meaningfully more than a window open and the duvet pulled back is one the evidence has not yet answered.
The challenge is that the research supporting cool bedrooms does not straightforwardly translate into research supporting expensive active cooling systems. Most of the evidence is for environmental temperature (room temperature between approximately 15 and 22 degrees Celsius) rather than for localised mattress cooling. Humans regulate body temperature during sleep partly through natural adjustments, pulling the duvet back, moving limbs outside the covers, naturally shifting position. A 2025 randomised trial of a temperature-controlled mattress cover found significant improvements in subjective sleep quality and thermal comfort, but no significant differences in objective sleep metrics from actigraphy [2]. People felt better, but the objective measurements did not change.
A practical concern is that in the UK context, where summer temperatures rarely exceed 25 degrees Celsius for sustained periods and most bedrooms are naturally cool for much of the year, the case for a two-thousand-pound cooling mattress is much weaker than in climates where bedroom temperatures regularly exceed 28 or 30 degrees Celsius at night. Opening a window, using lighter bedding in warmer months, or a standard fan providing airflow may produce a very similar effect at negligible cost. I am not dismissing these products, and in genuinely hot climates they may have real utility. But I would encourage you to evaluate the evidence, not the marketing, before spending significant money.
Pink Noise, Brown Noise, and Sound Machines
White noise machines have been used as a sleep aid for years, based on the idea that a consistent sound background masks disruptive environmental noises such as traffic, a partner's breathing, or intermittent sounds that might cause arousals. Pink noise is a version of broadband noise weighted to have more power at lower frequencies, giving it a softer, more natural quality (think rainfall or wind). Brown noise has even more energy at the lower frequencies.
The evidence for noise masking to maintain sleep in environments with unpredictable sound disturbances is intuitively reasonable, and there is some support for it. A 2020 systematic review of studies examining continuous noise and sleep by Riedy and colleagues found highly variable results across 38 included studies, with some showing improvement and others showing disruption [3]. The reviewers rated the quality of evidence as very low, largely because of enormous heterogeneity in how noise was characterised and measured across studies.
More interesting, and more relevant to the sleepmaxxing context, is research on phase-locked acoustic stimulation of slow-wave (deep) sleep. Several research groups have shown that delivering brief acoustic stimuli timed to the up-phase of slow oscillations during deep sleep can enhance slow-wave activity and improve memory consolidation. A 2021 meta-analysis by Wunderlin and colleagues covering ten studies with 177 participants found a combined effect size of 0.25 for acoustic stimulation on overnight episodic memory consolidation, which is small to moderate [4]. Crucially, the authors noted that the quality of evidence was not yet sufficient to recommend commercial devices for this purpose, and that the effects were more robust in younger adults.
The idea of enhancing deep sleep with specifically timed acoustic stimulation is genuinely interesting science. The consumer devices making this claim are largely ahead of the clinical evidence, and individual responses vary substantially.
For most people, the most practical application of noise machines is simply masking: reducing the disruption caused by an unpredictable noise environment, whether that is a snoring partner, traffic, or thin walls. For this purpose, the distinction between white, pink, and brown noise is probably less important than simply finding a sound that feels neutral and non-distracting. The other potential benefit is for people who are highly hyperaroused at night and tend to be startled easily into wakefulness by small sounds. A consistent sound background raises the effective threshold for those arousals, which may meaningfully improve sleep continuity. This is a low-risk intervention, costs very little, and has reasonable face validity. Just be aware that very loud continuous noise may itself disrupt sleep and carries potential implications for hearing health over the long term.
References
[1] Chevance G, et al. A systematic review of ambient heat and sleep in a warming climate. Sleep Medicine Reviews. 2023;68:101765. Systematic review of studies examining real-world ambient temperature and sleep; higher outdoor or indoor temperatures generally associated with degraded sleep quality and quantity; effects strongest during hottest months, in vulnerable populations, and in warmer regions.
[2] Stevenson S, et al. Under the Covers: The Effect of a Temperature-Controlled Mattress Cover on Sleep and Perceptual Measures in Healthy Adults. Clocks and Sleep. 2025. 34 healthy adults; randomised crossover; 14 nights with temperature feature on or off; significant improvements in subjective sleep quality and thermal comfort but no significant differences in objective actigraphy measures.
[3] Riedy SM, et al. Noise as a sleep aid: A systematic review. Sleep Medicine Reviews. 2020;55:101385. Systematic review of 38 studies examining continuous noise and sleep; highly variable findings; evidence quality rated very low; both improvement and disruption reported across different studies.
[4] Wunderlin M, et al. Modulating overnight memory consolidation by acoustic stimulation during slow wave sleep: a systematic review and meta-analysis. Sleep. 2021;44(1):zsaa151. 10 studies, 177 participants; combined effect size g=0.25 for episodic memory consolidation; subgroup of phase-locked stimulation approaches in young adults showed stronger effects (g=0.44); evidence insufficient to recommend commercial devices.
Contact Professor Vik Veer
If you would like to know more or to arrange a consultation, please use the links below.
Private secretary: 0207 458 4584