What Causes Insomnia?

Insomnia—difficulty falling asleep, staying asleep, or waking up too early—affects millions of people worldwide. While occasional sleepless nights are common, chronic insomnia can lead to daytime fatigue, mood changes, and impaired concentration. Understanding what causes insomnia is the first step toward finding strategies that help you get restful sleep.

How Common Is Insomnia?

• Up to 30% of adults report some symptoms of insomnia.*
• Around 10%–15% experience chronic insomnia that lasts three months or longer.*
• Women and older adults tend to report insomnia more often than men and younger people.

* Based on population studies of sleep patterns

Major Categories of Causes

Insomnia usually arises from a mix of factors. Experts classify these into three broad groups:

1. Physiological causes
2. Psychological causes
3. Behavioral and environmental causes

1. Physiological Causes

Medical conditions and certain substances can directly disrupt sleep:

• Chronic pain (arthritis, back pain)
• Respiratory issues (asthma, sleep apnea)
• Hormonal changes (menopause, thyroid disorders)
• Neurological disorders (Parkinson’s disease, Alzheimer’s)
• Medications such as some antidepressants, steroids, and blood pressure drugs
• Caffeine, nicotine, alcohol, and certain recreational drugs

If you suspect a medical issue is at the root of your sleep troubles, it’s important to discuss this with your doctor—some conditions may require prompt treatment.

2. Psychological Causes

Stress, worry, and mood disorders play a big role in preventing quality sleep:

• Stressful life events (job loss, relationship changes, bereavement)
• Anxiety and generalized worry about work, health, finances
• Depression, which can disrupt both falling asleep and staying asleep
• Post-traumatic stress, leading to nightmares or hyperarousal

Dr. Allison Harvey’s cognitive model of insomnia shows how negative thoughts about sleep (“I’ll never fall asleep”) create a vicious cycle: worry keeps you awake, which then increases anxiety about future nights.

3. Behavioral and Environmental Causes

Your habits and surroundings shape your sleep patterns:

• Poor sleep hygiene
  • Irregular bedtime or wake-up schedules
  • Using the bedroom for work or screen time
  • Excessive napping during the day
• Stimulating activities before bed—intense exercise, exciting TV shows, bright screens
• Suboptimal sleep environment
  • Noise, light, or uncomfortable temperature
  • An unsupportive mattress or pillow
• Shift work or jet lag, which disrupts your natural “body clock” (circadian rhythm)

Dr. Michael Perlis and colleagues describe how behaviors like lying in bed awake for hours actually train your brain to associate your bedroom with sleeplessness.

How Different Models Explain Insomnia

Experts use various frameworks to understand insomnia’s development:

• Roth’s Model highlights interplay between predisposing factors (genetics, personality), precipitating events (stress), and perpetuating behaviors (bad sleep habits).
• Perlis’s Behavioral Model focuses on how bed-time routines and sleep-related behaviors reinforce insomnia.
• Harvey’s Cognitive Model centers on worry, hyperarousal, and unhelpful beliefs about sleep.

Together, these models show insomnia isn’t just one thing—it’s a cycle of thoughts, behaviors, and physical reactions that feed on each other.

Common Triggers and Risk Factors

While everyone’s experience is unique, certain triggers and risks often appear:

• Family history of insomnia or mental health disorders
• Personal history of trauma or chronic stress
• High-pressure jobs or caregiving responsibilities
• Frequent travel across time zones
• Living in noisy or crowded settings
• Use of electronic devices close to bedtime

Signs You May Have Insomnia

• Trouble falling asleep (taking more than 30 minutes)
• Waking up frequently or too early and being unable to return to sleep
• Daytime tiredness, irritability, or slowed thinking
• Worrying about sleep each night
• Dependence on sleep aids (prescription, over-the-counter, or alcohol)

If these symptoms persist for weeks or months, it’s worth exploring both self-help strategies and professional support.

Practical Steps to Address Insomnia

1. Establish a consistent sleep schedule
   • Go to bed and wake up at the same time every day.
2. Create a calming pre-sleep routine
   • Read a book, take a warm shower, practice gentle stretching or meditation.
3. Optimize your bedroom
   • Keep it dark, quiet, and cool (around 60–67°F or 15–19°C).
   • Invest in comfortable bedding.
4. Limit stimulants and screen time
   • Avoid caffeine and nicotine in the late afternoon and evening.
   • Stop using smartphones, tablets, or computers at least an hour before bed.
5. Be active—but time workouts early
   • Regular exercise can improve sleep, but vigorous activity too close to bedtime can be stimulating.
6. Avoid long day naps
   • If you need a nap, keep it under 30 minutes and before mid-afternoon.
7. Manage stress and worry
   • Use journaling to offload concerns before bed.
   • Try relaxation exercises (deep breathing, progressive muscle relaxation).

When to Seek Professional Help

• Your sleep problems last longer than three months and occur at least three nights per week.
• You experience severe daytime impairment (falling asleep at unsafe moments, serious mood changes).
• You think an underlying health issue or medication is contributing.

Consider doing a free, online symptom check for insomnia to get personalized feedback and next-step suggestions.

Treatment Options

Depending on severity and underlying causes, treatments include:

• Cognitive Behavioral Therapy for Insomnia (CBT-I)
  • Considered first-line treatment; addresses thoughts and behaviors that maintain insomnia.
• Prescription sleep aids
  • Short-term use under medical supervision; risk of tolerance and dependence.
• Over-the-counter remedies (melatonin, antihistamines)
  • May help in the short run; discuss with a pharmacist or doctor.
• Alternative methods
  • Relaxation therapy, acupuncture, mindfulness meditation.

Take-Home Message

Insomnia is rarely caused by a single factor. It often involves an intricate mix of medical issues, mental-health challenges, daily habits, and environmental influences. By understanding what causes insomnia, you can take steps to break the cycle:

• Improve sleep routines and environment
• Address stress and unhelpful sleep thoughts
• Seek professional guidance when needed

If you ever experience symptoms that could be life-threatening—such as difficulty breathing at night, severe chest pain, or thoughts of harming yourself—please seek immediate medical attention or call emergency services. For persistent sleep troubles, speak to your doctor or a qualified sleep specialist about the best approach for your situation.