The current clinical consensus is that daily melatonin consumption is considered safe. However, according to a 2020 article published in Antioxidants, more research is needed to determine the correct dose and time and understand potential long-term effects.
Regardless of whether it truly helps with sleep or not, Dr. Ramkissoon doesn't recommend taking melatonin long-term.
Taking an unknown dose of serotonin for a long time can affect your heart, blood vessels, and brain. People taking medication for a mood disorder should be especially careful, as these medications already boost serotonin so an extra dose of serotonin can particularly impact them.
How many 10 mg melatonin should you take? In adults, 10 mg is the maximum recommended dosage. However, most people do not need doses of melatonin this high. While there is no risk of addiction, research shows that melatonin administration is effective at the lowest dose for the short term.
Melatonin is not associated with weight gain.
Do not use melatonin if you are pregnant or breastfeeding or have an autoimmune disorder, a seizure disorder or depression. Talk to your health care provider if you have diabetes or high blood pressure.
Furthermore melatonin has been shown to have valuable effects on cardiovascular health, blood pressure, and endothelial function and it might benefit patients with heart failure.
Most people overdo it with melatonin by taking upward of 10 milligrams or more prior to bed and then claim it doesn't work. Taking too much melatonin can actually cause rebound insomnia —either rendering the supplement ineffective or worse, exacerbating your already sleepless nights further.
In the UK and most of Europe, it's classed as a medicine, not a health supplement and as such, requires a prescription. This is because melatonin is considered “medical by function” which means that it requires a drug licence.
In several clinical trials, melatonin was found to be well tolerated and not associated with serum enzyme elevations or evidence of liver injury. Despite wide scale use, melatonin has not been convincingly linked to instances of clinically apparent liver injury.
Sometimes your doctor will recommend that you only take melatonin 2 or 3 times a week to see if that improves your sleep first. Melatonin should only be taken for a maximum of 13 weeks to treat short-term sleep problems in adults, but longer courses may be used on the advice of a specialist.
Does Melatonin Make It Hard to Wake Up? There is a low risk of fast-release melatonin or low doses of melatonin causing side effects such as grogginess after waking up. However, taking higher doses of melatonin or extended-release melatonin may lead to daytime sleepiness or drowsiness in some people.
Stopping the use of melatonin
You should not get any harmful discontinuation or withdrawal effects if you stop taking melatonin. However, you may get your old symptoms back. If you are on a high dose, then the doctor may wish to reduce the dose slowly before stopping it completely.
You cannot build up a tolerance to melatonin. This means that the same dosage of melatonin taken every day will not build up in the body, and you won't need a higher dosage over time to experience the same effect.
Melatonin's target sites are both central and peripheral. Binding sites have been found in many areas of the brain, including the pars tuberalis and hypothalamus, but also in the cells of the immune system, gonads, kidney, and the cardiovascular system (39, 40).
What are the health benefits of taking melatonin? Melatonin supplements may help with certain conditions, such as jet lag, delayed sleep-wake phase disorder, some sleep disorders in children, and anxiety before and after surgery.
Symptoms of Melatonin Overdose
Generally, an adult dose is thought to be between 1 and 10 mg. Doses near the 30 mg mark are usually considered to be harmful.
You Might Increase Your Risk for Some Health Issues
"For example, some people might experience side effects after taking melatonin, including drowsiness, stomach aches or dizziness," says Dr. Weiss. Since supplemental melatonin is relatively new in the grand scheme of human existence, the long-term effects are TBD.
The research findings suggest that melatonin has a beneficial effect on body composition and fat oxidation (burning). Supplementing with melatonin for 12 months could help reduce body fat, increase lean mass, and increase levels of adiponectin (which improves fat burning).
Hormones such as adrenaline, testosterone, dihydrotestosterone (DHT), and enzymes such as 5-alpha reductase are monitored and regulated during the sleep cycle when melatonin is generated. Too little melatonin can allow these to go out of balance and that may result in thinning hair.