Sleep problems in children's mental health

Sleep difficulties affect between 50 and 75 per cent of children and young people with mental health conditions, compared with around 25 per cent of the general paediatric population. This is not coincidental. Sleep and mental health have a bidirectional relationship: poor mental health disrupts sleep, and poor sleep worsens mental health. Inadequate sleep reduces emotional regulation capacity, increases anxiety, impairs concentration and memory consolidation, and lowers the threshold at which the brain perceives threats. For a young person already struggling with anxiety, ADHD, or depression, poor sleep is not simply a side effect. It is an active maintaining factor that needs to be addressed alongside the primary condition.

How different conditions affect sleep

Anxiety typically produces difficulties getting to sleep: the young person lies awake with an active, ruminative mind that cannot disengage from worry. The bedroom becomes associated with anxiety rather than rest. Hyperarousal (the physiological state of threat readiness) is incompatible with the neurological transition to sleep. ADHD produces a different pattern: many children with ADHD have delayed sleep phase syndrome, a circadian rhythm disruption in which the brain is not ready to sleep until two or three hours after a conventional bedtime. Forcing an early bedtime does not resolve this; it simply means the child lies awake longer. Depression is associated with early morning waking: the child falls asleep normally but wakes at four or five in the morning with low mood and cannot return to sleep. Trauma is associated with nightmares, hypervigilance at bedtime, and fear of the dark.

The role of screens and light

Blue light emitted by smartphones, tablets, and computer screens suppresses melatonin production, delaying the onset of biological sleepiness by up to ninety minutes. This effect is physiological, not a matter of willpower or discipline. A young person using a smartphone in a dark bedroom at ten o'clock is not simply being disobedient; their brain is receiving a signal that it is mid-afternoon. The social and emotional content of social media interactions adds a further layer of arousal that compounds the light effect. The combination of delayed melatonin, social comparison, and the unpredictable reward schedule of social media notifications creates a set of conditions that are extremely hostile to sleep onset. Device removal from the bedroom at a consistent time is one of the most evidence-supported sleep interventions available.

Cognitive behavioural therapy for insomnia in young people

CBT for insomnia (CBT-I) is the most evidence-based treatment for chronic sleep difficulties and is recommended by NICE ahead of sleep medication for most presentations. Adapted versions for children and adolescents address the cognitive and behavioural factors that maintain insomnia: unhelpful beliefs about sleep, inconsistent sleep schedules, excessive time in bed, and the development of conditioned arousal in the bedroom. Key components include sleep restriction (temporarily limiting time in bed to consolidate sleep efficiency), stimulus control, relaxation techniques, and psychoeducation about sleep. Results are typically seen within four to six weeks and, unlike medication, the effects are maintained after treatment ends.

Melatonin: what it is and what it is not

Melatonin is a naturally occurring hormone that signals to the brain that darkness has arrived and sleep should begin. Exogenous melatonin, taken as a supplement or medication, is not a sleeping tablet. It does not produce sedation; it shifts the circadian clock. This makes it most useful for delayed sleep phase presentations, which are particularly common in adolescents and in children with ADHD or autism. Melatonin has a good safety profile in the short to medium term and is now licensed in the UK for children aged six and over with ADHD-related sleep difficulties. It is not a substitute for behavioural sleep interventions, and for most insomnia presentations without a circadian component, CBT-I is a more appropriate first-line treatment.

Practical steps that make a meaningful difference

Consistency is the single most important factor in sleep hygiene: a consistent wake time seven days a week, including weekends, is more important than a consistent bedtime, because the wake time anchors the circadian rhythm. Bright light exposure in the morning (ideally natural daylight) reinforces this anchor. Avoiding screens for at least an hour before bed, keeping the bedroom cool and dark, and not using the bed for activities other than sleep all reduce the association between the bed and wakefulness. Exercise improves sleep quality substantially, though vigorous exercise in the two hours before bed can increase arousal. If sleep difficulties are severe or persistent despite consistent sleep hygiene, clinical assessment is appropriate. Sleep problems that are left unaddressed extend and compound the mental health difficulties they accompany.