Melatonin Test: When Is It Necessary and How to Interpret

What Is Melatonin?

Melatonin is a natural hormone that helps regulate your sleep. It’s produced in the pineal gland in your brain, mainly during the night, and tells your body it’s time to sleep. 

This process starts with tryptophan, an amino acid, and is linked to serotonin, another important hormone.

Melatonin doesn’t just affect sleep—it also plays a role in mood, puberty, and some immune responses. 

When Is Melatonin Testing Recommended?

While doctors sometimes check melatonin levels when you have trouble sleeping, this test is uncommon and not routinely performed. Additionally, it has not been approved by the U.S. Food and Drug Administration (FDA) for widespread clinical use. 

It is often used in research or specific cases where understanding melatonin levels is essential:

• Trouble falling or staying asleep.
• Jet lag that lasts longer than usual.
• Depression or mood disorders.
• Abnormal menstruation.
• Neurological problems, like multiple sclerosis.
• Heart issues, such as coronary artery disease.
• Problems related to hormone imbalance.

How Is Melatonin Testing Done?

Melatonin is usually tested through a blood test. This test measures how much melatonin is in your body, usually at specific times of the day. Sometimes saliva or urine tests are used, but blood tests are the most accurate.

Generally, no special preparation for the test is needed. However, it's important to inform your doctor about any medications you're taking, as some can affect melatonin levels. Your doctor may provide specific instructions based on your situation.

What Are Normal Melatonin Levels?

Normal melatonin levels usually range between 0.02-0.2 ng/mL.

Note: Normal ranges and measurement units can vary depending on the laboratory, the specific testing methods used, the time of day, and the patient’s age. Always discuss your results with a healthcare provider.

What Do Abnormal Melatonin Levels Mean?

High Melatonin Levels

If your melatonin levels are too high, it could be due to:

• Melatonin supplements: Overuse can raise levels too much.
• Delayed puberty: Late hormonal changes can increase melatonin.
• Menopause: Hormonal shifts during menopause may raise melatonin levels.
• Low libido: High melatonin can affect sexual desire.
• Mental health issues: Mental health issues, such as bipolar disorder, seasonal affective disorder (SAD), and major depressive disorder, can lead to high melatonin levels.
• Pineal gland problems: The pineal gland produces melatonin, and any issues here can cause an increase.

• Reduce or stop taking melatonin supplements (with your doctor’s approval).
• Maintain a consistent sleep schedule to balance melatonin production.
• Seek medical advice to address hormonal or gland-related issues.
• Practice calming activities, like gentle exercise or meditation.

Low Melatonin Levels

Low levels of melatonin can happen for several reasons:

• Poor nutrition: Not eating enough or lacking key nutrients affects melatonin production.
• Vitamin or mineral deficiencies: Your body needs these to produce melatonin.
• Certain medications: Certain medications, such as beta-blockers, antidepressants, and nonsteroidal anti-inflammatory drugs (NSAIDs), can suppress melatonin levels.
• Sleep disruptions: An irregular sleep pattern can reduce natural melatonin.
• Liver problems: The liver plays a part in melatonin synthesis; any issues here can cause lower levels.

• Eat foods high in tryptophan, such as nuts, seeds, and eggs.
• Avoid screens before bed to let your body produce melatonin naturally.
• Follow a regular sleep routine, even on weekends.
• Talk to your doctor about adjusting medications if needed.

Which Specialist Should You See?

If your melatonin test shows abnormal results, you may need to see a specialist. Here are some options:

• Family Doctor: For general advice and initial evaluations.
• Endocrinologist: For hormonal or gland-related problems.
• Gynecologist: If issues related to reproductive health or menopause.
• Neurologist: For sleep disorders or other nervous system problems.