What Is Melatonin
Melatonin is a hormone produced by your pineal gland when light exposure decreases. It communicates to your brain and body that sleep should begin. Your melatonin levels typically rise around 9 PM, peak between midnight and 3 AM, then drop gradually through the morning hours. This cycle aligns with your circadian rhythm, the 24-hour internal clock that governs sleep, body temperature, and hormone release.
How Your Body Makes and Uses Melatonin
The pineal gland produces melatonin from the neurotransmitter serotonin. This conversion happens in darkness. When light enters your eyes, photoreceptors send signals to suppress melatonin production, which is why exposure to screens before bed can delay sleep onset by 30 to 90 minutes. Your natural melatonin output declines with age. People in their 20s produce roughly 50% more melatonin than those over 50, which explains why insomnia becomes more common with aging.
Melatonin in Sleep Disorders
People with insomnia often have disrupted melatonin timing. Delayed Sleep Phase Disorder involves melatonin release happening too late, causing people to fall asleep at 2 AM or later. Advanced Sleep Phase Disorder causes early melatonin release, leading to 5 AM wake times.
Those with light exposure issues from night shift work or jet lag have misaligned melatonin peaks relative to their desired sleep schedule. Melatonin supplementation can help reset this timing when combined with light management, though timing matters significantly. Taking melatonin 2 to 3 hours before your target sleep time produces better results than taking it immediately before bed.
Cognitive Behavioral Therapy for Insomnia (CBT-I) addresses melatonin-related problems differently. Rather than replacing melatonin, CBT-I retrains your brain to respond naturally to darkness cues. This approach changes how your body regulates melatonin on its own, producing longer-lasting improvements than supplements alone.
Melatonin as a Supplement
Over-the-counter melatonin supplements range from 0.5 mg to 10 mg per dose. Research shows 0.5 to 3 mg is effective for most adults with circadian misalignment. Higher doses do not improve effectiveness and may cause morning grogginess. The FDA does not regulate melatonin as strictly as prescription medications, so product quality varies. Look for third-party testing certification on labels.
Melatonin works best for shift work adjustment, jet lag, and delayed sleep phase issues. It is less effective for primary insomnia when circadian timing is normal. Polysomnography testing can confirm whether your sleep problem stems from timing (where melatonin may help) or from other factors like sleep apnea (where other treatments are necessary).
Common Questions
- Is melatonin safe for long-term use? Melatonin appears safe for extended use, though research on durations longer than 3 years is limited. Unlike benzodiazepines, melatonin does not cause dependency or tolerance buildup. However, it works best as a short-term tool while you address underlying sleep patterns through sleep hygiene or CBT-I.
- Why does melatonin stop working after I take it for weeks? This typically reflects improved sleep habits or natural circadian adjustment rather than true tolerance. If effectiveness genuinely declines, discontinue use for 2 to 4 weeks, then reintroduce it. Rotating melatonin with other timing strategies (light exposure management, schedule consistency) maintains effectiveness.
- Can I take melatonin with other sleep medications? Consult your doctor before combining melatonin with prescription sleep aids, as interactions vary by medication. Melatonin generally pairs safely with antidepressants, but your prescriber needs to know all supplements you take.