How to sleep better: what the research actually says
Most sleep advice is either obvious or wrong. The gap between generic tips and what actually changes your sleep is wider than most people realise. Here is what the research says, stripped of the noise.
Go to bed at the same time. Cut the caffeine. Put your phone down. You already know all of it, and you are still lying awake at 2am. The problem with generic sleep advice is that it skips the mechanism. It tells you what to do without telling you why, which makes it easy to give up when it does not work in three days. The fix for most people’s sleep is not a new pill or a smarter tracker. It is a handful of specific changes, in the right order, based on how the biology actually works. We checked the research. Here is what stands up.
Why sleep feels harder than it used to, and why that is not just you
According to The Sleep Charity’s 2024 Sleep Manifesto, 37% of UK adults experience insomnia, and 9 in 10 people report problems with their sleep, with two-thirds of those having experienced difficulties for more than six years. A 2024 survey of 15,000 UK adults by Dreams found that 60% are sleeping six hours or fewer per night, significantly below the healthy minimum. The rates have been climbing for years. This is not a discipline problem. Modern life disrupts the biology of sleep in ways that willpower alone cannot fix.
Your body regulates sleep through two overlapping systems. The circadian rhythm is your internal 24-hour clock, anchored almost entirely by light. Sleep pressure is the build-up of adenosine in the brain the longer you are awake. When both systems sync, sleep happens without thinking about it. When either is knocked off by irregular schedules, artificial light, stress or alcohol, the whole thing gets noisy.
Matthew Walker, Professor of Neuroscience and Bioengineering at UT Dallas and director of the Sleep Innovation Laboratories, puts the priority plainly: “Regularity is king”. Anchor your sleep and wake times to the same slot every day, and you improve both how much sleep you get and how useful it is.
Chronic poor sleep affects mood, concentration, immune function, metabolism, and heart health. The NHS recommends most adults need between 7 and 9 hours a night, yet according to YouGov surveys cited in the 2024–25 Annual Public Health Report, while 80% of adults aim for at least eight hours, only 19% actually achieve it. Not as a target to chase, but as a baseline, the body needs to do its work. If you are running consistently under that, everything else you do for your health is working uphill.
How does stress actually damage sleep?
Stress and sleep sit inside a feedback loop. Poor sleep raises cortisol the next day. Raised cortisol makes it harder to fall asleep the next night. Breaking the loop usually means working both ends at once, which is why the Reduce Stress approach matters as much as anything you do at bedtime.
In practice, this means your evening routine is doing double duty. It is not only winding you down for sleep. It is lowering the cortisol curve that would otherwise fragment your sleep at 3am. A 2018 study in JMIR Mental Health found that even moderate alcohol consumption reduced sleep quality by around 24%, largely by suppressing REM sleep in the second half of the night. A 2024 systematic review and meta-analysis in Sleep Medicine Reviews, covering 27 studies, confirmed that even a low dose of alcohol, equivalent to roughly two standard drinks, delays the onset of REM sleep and reduces its duration, with disruption worsening progressively with higher doses. A separate 2024 study published in SLEEP found that alcohol before bed increased slow-wave sleep early in the night while consistently decreasing REM sleep accumulation with the effect persisting across consecutive nights. The glass of wine that helps you fall asleep faster is the same glass waking you up at 3am four hours later. If you regularly wake in the small hours, alcohol and stress are the two most likely culprits, and they often travel together.
What the research says matters more than what does not
Not everything that gets blamed for bad sleep is guilty. A clearer picture.
Light is the biggest lever. The circadian clock is set almost entirely by light, not by willpower or habit. Morning light within an hour of waking, ideally outside, anchors your rhythm and signals to every cell in your body that it is daytime. A 2017 study in Current Biology led by Kenneth Wright at the University of Colorado Boulder found that one week of natural light exposure shifted participants’ circadian clocks earlier and improved their sleep timing. Evening light does the opposite. The blue spectrum from screens suppresses melatonin and delays sleep onset, which is why a lit bedroom at 11pm is working against you even if you feel tired.
Temperature is a real one. Core body temperature naturally drops as you approach sleep, and a bedroom that is too warm interrupts the process. The Sleep Foundation recommends keeping your bedroom between 15 and 19°C. Cool enough to want a duvet. That is a physiological lever, not a comfort preference. Look at your Bedding before you look at a supplement.
Caffeine hangs around longer than you think. It has a half-life of around five to six hours, which means a morning coffee can still be circulating in the afternoon. If you are sensitive, even a 10am cup can shorten deep sleep that night. Walker’s rule of thumb is to cut caffeine 12 to 14 hours before bed. For a 10pm bedtime, that means nothing after 8am.
Alcohol is not a sleep aid. It sedates, which is not the same as sleeping. Sedation fragments REM and leaves you less rested after eight hours in bed than you would be after six without the drink.
The sleep routine that holds up to scrutiny
A sleep routine is not a wellness ritual. It is a set of signals you give your nervous system so it knows what is coming. Consistency is doing most of the work, which is why sporadic “good sleep weeks” feel less restorative than they should. You need the body to expect it.
Fix your wake time first. It is the single most useful change you can make. Your wake time anchors the circadian rhythm, and everything else follows from it. Sleeping in at weekends feels restorative but creates what researchers call social jetlag: the circadian equivalent of flying between time zones twice a week. If you get one thing right this month, pick a wake time and hold it.
Wind down properly. Give yourself 30 to 60 minutes before bed without anything cognitively demanding. Passive screen time is not enough, and content matters as much as light. Scrolling work email in warm reading mode is still scrolling work email. A warm bath is worth trying for a specific reason. Immersion in warm water raises skin temperature, which triggers the compensatory drop in core body temperature that initiates sleep. Reading a book in dim light does more than it looks like it should. The Stress & Sleep range is built around this principle.
Keep the bed for sleep. Working from bed, eating in bed or lying awake scrolling trains your brain to associate the bed with wakefulness. Not a glamorous piece of advice. The reason it works is that the brain learns context quickly, and once it has decided the bed is where you answer emails, it will keep you alert there. Rebuilding the association takes a few weeks of discipline. Your Bedroom & Sleep environment should cue one thing only.
Your wake time anchors everything else. Get that right, and most of the other pieces follow.
Does magnesium actually help you sleep?
The sleep supplement market is enormous and largely underregulated. Most products do not have the evidence behind them that their packaging implies. A few do.
Magnesium is the one worth knowing about. It plays a direct role in regulating the nervous system and GABA receptors, which calm neural activity before sleep. A 2012 study in the Journal of Research in Medical Sciences found that magnesium supplementation improved sleep time, sleep efficiency and early morning waking in older adults. This has since been reinforced by a landmark 2025 randomised controlled trial of 155 adults, published in Nature and Science of Sleep, which found magnesium bisglycinate (250mg elemental magnesium daily) produced a statistically significant reduction in insomnia severity scores versus placebo over four weeks, the largest placebo-controlled trial on magnesium and sleep conducted to date.
Form matters. Magnesium glycinate absorbs better than cheaper oxide forms and is less likely to cause digestive issues. Browse our Supplements for magnesium glycinate and other options that passed the Ziracle standard.
L-theanine, an amino acid found in green tea, has decent evidence for reducing sleep-onset anxiety without causing grogginess the next morning. A 2019 study in Nutrients found improvements in sleep quality and next-day cognitive performance in adults with stress-related symptoms. Worth trying if anxiety is what is keeping you awake rather than a circadian issue.
Melatonin works for shifting circadian timing, particularly for jet lag or shift work, but it is not a traditional sleep aid. It signals darkness to the brain rather than inducing sedation, which means taking it to “sleep better” on a regular schedule misses the point.
Ashwagandha and valerian have both been studied with mixed results. The honest position: the evidence is thinner than the marketing suggests. If they work for you, fine. The research does not yet justify building a routine around them.
What the evening toolkit looks like
The evidence points to a few consistent categories. None of these are loosely adjacent to sleep. Each is directly implicated in it.
The wind-down is where most people go wrong, because they treat it as optional. Products that support it, whether bath soaks, body oils, a simple skincare ritual or a low-stim candle, are not extras. They are cues to the nervous system that sleep is coming. The Aromatherapy range is built around the evening transition, with formulations that use lavender, chamomile and vetiver for their genuine sedative properties rather than because they smell expensive.
Stress support pulls double duty. Adaptogens, magnesium and breathwork tools lower the cortisol load that keeps the nervous system activated when you want to be winding down. If you have been reading sleep advice for years and nothing has stuck, the missing piece is usually this one. For a longer look at the evening side, our guide to stress routines covers what works beyond the obvious.
Sleep support at the supplement level is worth trying in order: magnesium glycinate first, L-theanine if anxiety is the block, glycine or tart cherry as secondary options. Stacking five things at once rarely tells you what is working. Prefer products certified Organic where the formulation allows, and look for B Corp brands where supply chain matters to you.
If you want to add something to your day rather than your night, meditation has some of the strongest evidence in the category. Even ten minutes before bed, or at a fixed point earlier in the day, reduces the sympathetic activity that keeps people awake. Our piece on daily meditation walks through the least annoying way to start, and our round-up of mindfulness picks covers the tools worth owning.
Where to start if you are still awake at 2am
If you are still lying awake at 2am, the answer is rarely a new supplement or a stricter bedtime. Wake-time consistency, morning light and a bedroom that works with your temperature rather than against it will do more than anything else. Get those right first, for three weeks, before you change anything else. Most people who do this find they do not need the supplements they were about to order.
Sleep is one of those things you only notice when it stops working. The fix is not a product. It is a sequence.
Start with the wake time.
Browse Sleep Better for products that passed the Ziracle standard on efficacy and ethics: Sleep Better.
FAQs
Middle-of-the-night waking is usually a sign of disrupted sleep architecture rather than trouble falling asleep. Alcohol in the evening is one of the most common causes, because it fragments the second half of the night. Raised cortisol from stress is another. If a 2am or 3am wake is consistent, it is worth paying attention to rather than waiting out.
Yes, within limits. The evidence is strongest for the glycinate and bisglycinate forms, which absorb better than cheaper oxide forms and are much less likely to cause digestive issues. A 2012 study in the Journal of Research in Medical Sciences first established the link, and a 2025 randomised controlled trial of 155 adults in Nature and Science of Sleep confirmed that magnesium bisglycinate significantly reduced insomnia severity scores versus placebo, with most improvement in the first two weeks. Not a silver bullet, but one of the few sleep supplements with genuine evidence behind it.
Expect two to three weeks before a new routine feels natural, and four to six weeks before the effects on sleep quality are clear. The temptation is to abandon it after three bad nights. Do not. The circadian system takes time to reset, and the first week is always the worst.
For most people, yes. Caffeine has a half-life of around five to six hours, which means a morning coffee can still be active in the body by mid-afternoon. If you are sensitive, even a 10am cup can shorten deep sleep that night. Try pushing your last cup to before 8am and see whether anything shifts.
It is less about the screen and more about what is on it. Blue light does suppress melatonin, but the bigger effect is cognitive. Scrolling work email, news or social media keeps the nervous system activated when it needs to wind down. A warm-toned reading mode helps. Reading a book helps more.
