Long-Term Side Effects of Melatonin

Individuals who suffer from occasional sleep difficulties may benefit from the short term effects of melatonin supplements. Melatonin is known for its effects on sleep cycle rhythms, and for its role as an antioxidant within the body. Relatively few short term effects are associated with the use of this drug, however, information regarding its long-term effects is uncertain.

Identification

• Melatonin is a naturally occurring hormone in the body that's secreted by the pineal gland and synthesized from the amino acid, tryptophan. As a person ages, melatonin levels gradually decrease over time. It's presence is associated with sleep cycles in humans, and is used as a supplement to treat certain sleep disorders. Melatonin is also known for its antioxidant effects on the immune system. Conflicting research results show both negative and positive results from long-term use, and so expected long-term side effects are unclear.

Function

• As an antioxidant, melatonin is found to aggressively attack free radicals within the body. Free radicals are byproducts from normal cellular processes. These molecules carry charges that can have adverse effects on cell structures. Melatonin's status as a hormone means its able to permeate every cell in the body, as well as the internal structures contained within cells. In terms of sleep cycle rhythms, melatonin levels may play a significant role in sleep disturbances. Melatonin levels are shown to be their highest right before bedtime. Low levels of melatonin may be associated with difficulties in falling asleep and staying asleep.

Anti-Aging Effects

• Melatonin's long-term antioxidant effects may contribute to the body's overall longevity througout the aging process. It's elimination of free radicals in the body works to reduce the effects of oxidative damage in the system. Oxidative damage is the result of unstable oxygen molecules, and contributes to the degeneration of system processes that accompanies the aging process. Degeneration caused by oxidative damage can impair blood glucose metabolism processes, decrease immune system responses and cause a breakdown of proteins in the body. Sustained levels of melatonin within the body may work to extend a person's life span in the long run.

Psychological Effects

• Long-term side effects of melatonin supplements on individuals with mild and major depression have been associated with a reduction in depression symptoms. Low levels of melatonin are believed to contribute to symptoms of mild and major depression, according to the University of Maryland Medical Center. When taken as a supplement, the hormone is shown to cause a surge in serotonin, a brain neurotransmitter involved in regulating the emotions. Possible adverse effects on the body's circadian rhythms require amounts to be administered in specified doses under a doctor's supervision.

Sleep Cycle Disturbances

• When taken in supplement form as a sleep aid, melatonin works to induce a state of relaxation and sleepiness. However, the body may respond by secreting less of its own melatonin when its natural levels are supplemented. In effect, a person would have to keep increasing the supplement dosage in order to obtain the same desired effects. As melatonin plays a key role in regulating the body's circadian rhythms, continued use can significantly offset the body's ability to regulate its sleep cycle. Symptoms of this condition may appear as fatigue, disorientation and insomnia.