Melatonin in Urine

Melatonin is a hormone produced by the pineal gland in response to darkness (decreasing light). It helps regulate the sleep-wake cycle, known as the circadian rhythm, and functions as a potent antioxidant. Melatonin production peaks at night, with blood levels rising sharply at dusk, leading to feelings of sleepiness. Melatonin is present in urine because it is excreted from the body this way. You can have this test done at IntroLab in Belgrade.

The Importance of Melatonin

Melatonin is essential for several vital functions, including protecting the cardiovascular system, regulating endocrine functions, modulating the immune system, and controlling body temperature. It also has significant antioxidant properties, stimulates the production of growth hormone, and helps alleviate symptoms of seasonal affective disorder (SAD).

Melatonin Urine Test

This test measures the levels of 6-Sulfatoxymelatonin (MT6s), the main metabolite of melatonin, in the urine. While MT6s itself is not physiologically active, its levels in urine reflect the body’s melatonin production. Low urinary MT6s levels may suggest the need for additional melatonin supplementation.

Clinical Significance

Low melatonin levels can lead to sleep issues (insomnia or waking during the night), a weakened immune system, mood changes, fatigue, and low growth hormone levels. High melatonin levels, on the other hand, can inhibit ovulation in women and lower body temperature.

Melatonin level changes may be linked to:

• Sleep disorders
• Stress
• Depression
• Anorexia nervosa
• Schizophrenia
• Sexual maturation during puberty
• Immune disorders

Procedure for Measuring Melatonin in Urine

For a melatonin urine test, a 20 ml urine sample is required. The samples are extracted and dried under nitrogen before immunoassay. Melatonin levels are measured using a competitive enzyme immunoassay (EIA) with anti-melatonin and biotinylated melatonin.