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Does melatonin decrease dopamine? The melatonin and dopamine sleep connection

Does melatonin decrease dopamine? This is definitely a question you’ll want to ask if you’re thinking of using melatonin to overcome your issues with insomnia. As a substance naturally produced by the human body, melatonin seems like a relatively safe way to improve your sleep habits. However, it’s not without its downsides. 

Though extremely effective for some people, melatonin can interact negatively with some substances. It can cause side effects like nausea or dizziness, and it may even be responsible for poor mood. That’s because melatonin and dopamine seem to have a connection. 

Today, we’re going to be looking at the interactions between dopamine and melatonin you need to know, before you begin considering taking supplements.  

What you need to know about melatonin and dopamine

Dopamine is one of the better-known neurotransmitters in the human brain. This natural chemical plays a variety of crucial roles in ensuring the proper functioning of the human body. 

It’s responsible for things like creativity (or laziness when you’re lacking dopamine), and it also has a significant impact on your mood. In short, dopamine gets released from the nerve cells by stimulation and gives you motivation to get stuff done. 

According to recent studies, dopamine and melatonin also have a significant connection which may have an influence on our ability to maintain a stable circadian rhythm.

Melatonin, if you’re unfamiliar, is one of the most important organic chemicals in the body associated with sleep. It helps to signal to the brain when it’s time for you to rest. Usually, your brain is triggered to release melatonin at night, when it’s naturally dark. 

According to studies, dopamine has a somewhat counteractive effect to melatonin. Drugs responsible for increasing levels of dopamine in the brain, like Ritalin, can also increase feelings of wakefulness.

In most people the balance of dopamine and melatonin naturally evens out throughout the day, with your dopamine increasing while you’re awake, and your melatonin peaking when it’s time to sleep. 

Of course, if you take melatonin supplements to improve your sleep, or help you get to sleep at night, this could off-set the balance, leading to problems with dopamine release. Contrary to use of melatonin, adding dopamine to your system can also change your circadian rhythm.

Should you be concerned about melatonin and dopamine?

Dopamine and sleep clearly have a scientific connection. So, does melatonin decrease dopamine?Studies show when dopamine latches onto a receptor in a specific part of the brain, it signals the body to “wake up” by turning down the levels melatonin in your system. 

One group of researchers specifically asked the question “how does dopamine affect melatonin”. They found dopamine receptor 4 (a protein on the outside of some cells responsible for binding to dopamine) is active in the pineal gland.

The pineal gland is responsible for regulating your internal clock, or circadian rhythm, by releasing melatonin in response to darkness or light.

The scientists found the presence of this dopamine receptor on the pineal gland cells naturally changed with the time of day. Numbers where higher at night and lower during the day. As a result, researchers believe the dopamine receptor 4 protein may be relevant to our circadian rhythm.

During the night, the pineal gland produces the hormone melatonin, which makes you sleepy. This substance is produced in response to norepinephrine, another naturally-occurring hormone in the human body.

When additional dopamine is present in the brain, the D4 receptor hooks onto the outside of the gland with norepinephrine receptors, reducing the melatonin secretion signal when it’s time to rise and shine. 

How does melatonin affect dopamine?

So, we know dopamine and melatonin have a connection in one direction. Dopamine reduces the impact of melatonin on your mind and body. But does melatonin decrease dopamine? It seems it does.

Naturally, the norepinephrine complex in the brain increases melatonin levels at night. Hereby enhancing your sleepiness. In the morning, dopamine and its receptors form a complex of proteins designed to make you feel more active and awake. 

When dopamine reacts with its receptor, and the receptor is paired with the norepinephrine receptor outside the pineal cells, this interferes with the signals sent into the cell, reducing melatonin production. 

Fortunately, the light-dark cycle influencing the release of dopamine means the dopamine and norepinephrine combination really only happens at the end of the night. 

Where things start to get complicated is when unusual amounts of melatonin or dopamine enter your system. Taking a substance which heightens your dopamine levels would mess with your natural circadian rhythm, keeping you awake for longer. 

In the same vein, taking regular melatonin would disrupt the flow of dopamine in your brain. This could potentially cause a range of problems. For instance, reduced dopamine in the human body can lead to reduced motivation and increased symptoms of Parkinson’s and RLS. 

If you’re wondering “does melatonin inhibit serotonin” – another form of feel-good chemical created by the brain, you’re in luck. Some studies indicate a small dose of melatonin can actually improve your serotonin levels. Of course, this means you will need to be cautious about taking melatonin at the same time as serotonin-boosting drugs.  

Does melatonin decrease dopamine?

Further study into the connection between dopamine and melatonin is definitely required. We need to develop a better understanding of the way all our organic chemicals influence sleep. But, current studies do suggest dopamine and melatonin have a significant relationship. 

According to one study, the introduction of melatonin over a 5-week period reduced the production of dopamine in the posterior pituitary by 50%. 

The natural connection between dopamine and melatonin in the brain means it’s important to be cautious about the way you use supplements. While melatonin can be a useful tool for people with insomnia issues, it could be dangerous if low dopamine can present significant issues for you. 

Already, most medical professionals recommend staying away from melatonin if you fall into specific categories. For instance, you should likely avoid melatonin if you have:

Chronic insomnia
If you’ve been struggling to fall asleep for longer than a month, it’s probably best to stay away from melatonin. According to the American College of Physicians and Academy of Sleep Medicine, other remedies are often safer. You might want to consider making some lifestyle changes. This could be updating your sleep hygiene strategy, and exploring therapeutic strategies like CBT.

Restless Legs Syndrome
RLS is a common problem for people with insomnia, and something frequently associated with other sleep conditions. If you do have Restless Legs Syndrome, lowering levels of dopamine in the brain can be particularly problematic for you. If you’ve been diagnosed with this condition, your doctor will often advice looking at other therapeutic strategies. 

Dementia
Dementia can have a significant impact on the way you live and sleep. Often, dementia is associated with insomnia. This can lead to significant problems for both patients and caregivers alike. Melatonin can sometimes make the condition worse for people, because dementia can cause the body to metabolize the supplement faster. In moderate or severe dementia, melatonin supplementation can increase the risk of falls.

Understanding melatonin, dopamine, and sleep

Taking melatonin does have its benefits. Crucially, it’s important to know exactly how taking a sleep supplement is going to influence you in the long-term. 

Generally, taking melatonin an hour or two before bedtime is something many doctors will recommend for shorter periods. Evidence suggests this strategy can be effective in dealing with issues like jet lag when you’re travelling between time zones, for instance. 

Shift workers with irregular schedules can also benefit from regular melatonin use, as can people with a condition called delayed sleep-wake phase disorder, which makes it harder to fall asleep at night, leading to frequent issues of daytime fatigue. 

Even older people may be able to use melatonin to improve their sleep pattern, as melatonin production can naturally decline with age. This means you’re less likely to create an imbalance between melatonin and dopamine at a later stage in your life. 

Generally speaking melatonin is rarely a one-size-fits-all solution for long-term sleep management. It can frequently cause problems with things like nausea and day-time drowsiness, which may mean it’s harder for you to live your life as normal, when you’re taking melatonin. 

Additionally, the evidence of melatonin’s ability to decrease dopamine levels means you’re at greater risk of mood disorders, and issues caused by low dopamine. 

Managing your sleep with melatonin

As with most things when it comes to improving sleep and overcoming insomnia, it’s best to speak to your doctor before taking action. Speaking to your healthcare provider will give you a good insight into whether taking melatonin short-term is a good idea for you – or whether it’s something you need to avoid based on your existing conditions.

For the most part, melatonin is a natural and relatively safe substance for people to use if they’re suffering from short-term periods of insomnia. However, you shouldn’t use melatonin without getting the insights of a doctor first. Your sleepiness could be a sign of something more significant, like a mental health issue, hormonal imbalance, or a sleep disorder, like sleep apnea.

Siestio. Sleep Matters.

Medical disclaimer
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