Why Can’t I Stay Asleep? Causes of Middle-of-the-Night Wakeups

Few things are as frustrating as waking up in the middle of the night, staring at the ceiling in the dark, and wondering why restful sleep keeps slipping away. This common experience can leave people feeling tired, irritable, and anxious about the day ahead. While waking once or twice during the night is relatively normal, frequent or prolonged wakeups can affect overall wellbeing.

If broken sleep has become a regular pattern, it’s time to investigate what might be behind it—because understanding the cause is the first step to getting back to restorative rest.

Normal vs Abnormal Night Waking

It’s perfectly natural to wake up briefly during the night. In fact, the human sleep cycle consists of several 90-minute phases, and light awakenings can occur during transitions between these stages. These micro-awakenings often go unnoticed and don’t disrupt sleep quality unless they’re prolonged or happen too often.

However, when someone:

• Regularly wakes multiple times a night,

• Struggles to fall back asleep,

• Or wakes for long stretches (20+ minutes),

…it may signal an underlying issue.

Normal night waking includes:

• Briefly waking after a REM cycle

• Waking to use the toilet (once per night is common)

• Waking due to external noises or temperature changes

Abnormal patterns may include:

• Waking at the same time every night (e.g., 3am)

• Waking due to panic or racing thoughts

• Waking soaked in sweat or short of breath

Understanding whether night wakings fall within a typical range or hint at something deeper is essential for addressing the problem.

Medical and Hormonal Causes

Sleep Apnoea

One of the most common medical causes of middle-of-the-night waking is obstructive sleep apnoea (OSA). This condition causes repeated pauses in breathing during sleep, often accompanied by loud snoring, gasping, or choking. The result? Frequent awakenings as the body restarts breathing. OSA is often underdiagnosed and linked to daytime fatigue, high blood pressure, and poor concentration.

According to the NHS, sleep apnoea is more common in men, older adults, and people with excess weight. It can often be managed with lifestyle changes or the use of a CPAP machine.

Blood Sugar Imbalances

People with low blood sugar (hypoglycaemia), especially those with diabetes or insulin resistance, may experience nocturnal wakeups. Blood sugar dips can trigger the release of adrenaline and cortisol, which may jolt the body awake. Consuming too many refined carbs or sugars close to bedtime can contribute to this effect.

Cortisol Dysregulation

Cortisol is a stress hormone that follows a circadian rhythm—normally rising in the early morning to help wake the body. However, in people with chronic stress, burnout, or adrenal dysfunction, cortisol may spike too early, such as at 2–4am, causing early wakings and anxiety.

Studies published in journals like Psychoneuroendocrinology show that elevated night-time cortisol levels are linked to insomnia, especially when combined with emotional stress.

Menopause and Hormonal Changes

Hormonal fluctuations during perimenopause and menopause can significantly affect sleep. Night sweats, hot flashes, and changing levels of oestrogen and progesterone contribute to frequent wakings. The NHS confirms that sleep issues are a major complaint during menopause, often requiring a holistic approach including hormone replacement therapy (HRT), lifestyle adjustments, and stress management.

Other Medical Conditions

Additional health conditions that may disturb sleep include:

• Chronic pain syndromes (e.g., fibromyalgia, arthritis)

• Nocturia (frequent night urination)

• Restless legs syndrome (RLS)

• Gastroesophageal reflux disease (GERD)

• Thyroid imbalances

A GP or sleep specialist can run appropriate tests to rule out these causes.

Lifestyle Factors

Often overlooked, daily habits play a huge role in how well sleep is maintained.

Caffeine

Caffeine has a half-life of around 5–6 hours, meaning a 3pm coffee can still affect the body at bedtime. Caffeine not only makes it harder to fall asleep but can reduce deep sleep and cause fragmented sleep later in the night.

Consider switching to decaf after midday and avoiding caffeinated sodas or chocolate in the evening.

Alcohol

While alcohol may initially make you drowsy, it disrupts REM sleep and increases the likelihood of waking up in the second half of the night. Studies from the Journal of Clinical Sleep Medicine confirm that alcohol reduces sleep quality and alters sleep architecture.

Blue Light and Screens

Using screens before bed delays melatonin production—the hormone that signals it’s time to sleep. Engaging with social media or watching intense content can also cause mental overstimulation, making it harder to stay asleep.

Opt for blue-light filters or dim lighting in the evening, and try to stop screen use an hour before bed.

Evening Eating and Hydration

Heavy meals, late-night snacking, or excessive liquids can cause:

• Acid reflux

• Increased urination

• Digestive discomfort

Try to finish eating at least 2–3 hours before bed and gradually reduce fluid intake in the evening.

Mental Health and Stress

Anxiety and Racing Thoughts

Waking up in the night with spiralling thoughts is a hallmark of stress-related insomnia. The stillness and silence of night can amplify worries. This type of hyperarousal keeps the body in a state of readiness, even during supposed rest.

Practices like journaling before bed, guided meditations, and relaxation techniques can help.

Depression

Depression is often associated with early morning wakings, such as 4–5am, accompanied by a sense of dread or emptiness. According to The Lancet Psychiatry, depression disrupts the balance of REM and non-REM sleep, resulting in poor sleep quality overall.

Trauma and PTSD

People with trauma or PTSD may wake due to nightmares, night terrors, or hypervigilance. Even when conscious memories aren't triggered, the body may remain alert, interrupting sleep.

Therapies such as EMDR, CBT, or trauma-informed mindfulness can offer long-term solutions.

The 3AM Wakeup Phenomenon

It’s common to hear people say: “Why do I always wake up at 3am?”

This specific time has become infamous in folklore, often dubbed “the witching hour”. While these spiritual theories are popular online, biological explanations are much more likely.

Circadian Rhythms

At around 3am, core body temperature is at its lowest, and melatonin production begins to taper as cortisol gradually rises. These natural changes can make the body more susceptible to waking.

Sleep Cycle Transitions

We move through 4–6 complete sleep cycles per night. Waking during a light sleep stage, especially near cycle transitions, is normal. People who are anxious or light sleepers may be more likely to remain awake once stirred.

Chinese Medicine Interpretation

In Traditional Chinese Medicine (TCM), the liver is thought to be most active between 1–3am. Emotional stress, toxin buildup, or unresolved anger are believed to disturb sleep during this window. While not evidence-based by Western standards, some find TCM perspectives helpful when used in conjunction with conventional approaches.

What To Do When You Wake Up in the Middle of the Night

Waking in the night isn’t inherently a problem—staying awake is. Here’s what to do if that 2am restlessness hits:

Avoid the Clock

Watching the clock can increase anxiety and create negative associations with the night. If possible, keep it out of sight.

Stay in Bed (But Not Restless)

If you can’t fall back asleep after 15–20 minutes, get up and do something calming in low light—like reading or stretching—then return to bed when drowsy.

Use Calming Techniques

• Deep breathing

• Progressive muscle relaxation

• Visualisation (e.g., imagining a peaceful scene)

Avoid Stimuli

Do not reach for your phone or turn on bright lights. Avoid stimulating tasks like housework or writing emails.

How to Stay Asleep Longer – Practical Fixes

Create a Sleep-Friendly Environment

• Keep the bedroom cool (16–18°C)

• Use blackout curtains to block light

• Reduce noise using earplugs or a white noise machine

• Keep electronics out of the bedroom

Establish a Wind-Down Routine

Your body needs cues that sleep is coming. Try:

• Herbal tea (chamomile, lemon balm)

• Warm bath or shower

• Low lighting and quiet music

Support Nutrient Needs

Some nutrients may support deeper sleep:

• Magnesium glycinate: known for relaxation

• Vitamin B6 and B12: support melatonin production

• L-theanine: an amino acid that promotes calm

Cognitive Behavioural Therapy for Insomnia (CBT-I)

CBT-I is the most effective long-term treatment for chronic insomnia. It addresses unhelpful beliefs and behaviours around sleep and teaches new patterns. Online CBT-I courses are now available in the UK and can be accessed via GP referral.

When to See a Sleep Specialist

If wakeups persist for more than 3 months, or interfere significantly with quality of life, it’s time to seek help.

Speak to a GP if:

• Snoring or gasping during sleep is reported

• Fatigue affects daytime function

• You suspect a hormonal imbalance

• You’ve already tried basic sleep hygiene without improvement

You may be referred to a:

• Sleep clinic for polysomnography (sleep study)

• Endocrinologist for hormone testing

• Therapist trained in CBT-I

Final Thoughts + Related Articles

Night wakings can be distressing, but they often have clear causes and manageable solutions. Whether the culprit is stress, sleep apnoea, or simply too much coffee, small changes and awareness can lead to major improvements.

Understanding your unique sleep patterns and stressors is the first step to regaining control. A combination of self-care, environment optimisation, and (if needed) professional guidance can help restore the deep, continuous rest everyone deserves.