Could Reset Your Circadian Rhythm

An estimated 25% of the US population suffer from some form of circadian rhythm disorder. [R] With it near impossible to avoid artificial light in the modern world this isn’t surprising but it also makes melatonin a highly useful supplement for a multiplicity of individuals. Melatonin has the ability to more strongly entrain circadian rhythms in the absence of normal light/dark cycles. This can benefit both people who are blind and cannot perceive light, people who have insomnia due to circadian issues but also hypothetically the healthy individual, who cannot escape unnatural light, meaning that a better circadian entrainment could benefit their mood, cognitive function and overall health. [R1] [R2] [R3] [R4] [R5]

Furthermore, both melatonin supplements and melatonin receptor agonists can shift the circadian rhythm forwards or backwards given that they are taken at sensitive times (8-11pm to advance so you wake up earlier or 12pm-3am to delay so you wake up later). This quality is incredibly useful for preventing of jet lag but also for anyone wanting to alter their sleep patterns. [R1] [R2] [R3] [R4]

Could Sleep Better

Slow-release melatonin supplementation improves sleep quality and the delay to sleep onset in elderly people and children with sleep-related issues. [R1] [R2] [R3] High doses of melatonin also enhance sleep quality in healthy rodents suggesting they supplementation may have benefits for the healthy person as well. [R1] [R2]

Ramelton, on the other hand, a very high affinity MT1 and MT2 receptor agonist, dramatically reduces sleep onset latency (time to fall asleep) and total sleep time in insomnia patients. [R] It is also much safer than commonly prescribed sleep medication such as benzodiazepines. [R]

While it is most commonly reported that melatonin-based drugs are not as powerful for insomnia prevention as GABAergic sleep medication (benzodiazepines, ambien/zolpidem, etc), they are safer, enhance sleep quality more, are effective for the long term and could additionally target the root of insomnia (depression, circadian issues, etc) rather than just knocking you out. [R]

May Have Antidepressant Activity

Chronic melatonin supplementation enhances hippocampal neurogenesis (neuronal growth), something that is suppressed in people with major depressive disorder, and is known to have an antidepressant effect. [R1] [R2] [R3] This enhanced the interest of the scientific community in melatonin, speculating that it could be a powerful antidepressant target. Unfortunately, most melatonin agonist seems to have very weak effects upon depression. That is, apart from one. [R]

Agomelatine is a mixed MT1 and MT2 agonist and 5HT2c (serotonin receptor 2c) antagonist. [R] In clinical trials, agomelatine is as effective as selective serotonin reuptake inhibitors (SSRIs) and serotonin/norepinephrine reuptake inhibitors (SNRIs) in treating depression but with a better side effect profile. [R]

Could Prevent Cancer

Population wide, natural serum concentrations of melatonin during the night are inversely associated with breast, lung and cervical cancer risk. [R] Indeed, according to David S and colleagues not only night shift workers but also those with the, “brightest bedrooms,” have a significantly higher risk of getting breast cancer. [R]

This has caused melatonin to be seriously looked at as a treatment for a variety of different cancers, including breast and prostate. [R] Thus far, melatonin treatment has been shown to enhance both the effectiveness and tolerability of chemotherapy in cancer treatment. [R]