What does the Pineal Gland do?

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Renee Descartes described the pineal gland as the "Seat of the Soul." This tiny gland can be located in the brain's center. So what makes this super tiny gland so important in our day-to-day functioning?

The pineal gland is a pea-sized and shaped gland located in the brain's center. While researchers do not yet fully understand its function, they do know that it produces and regulates hormones, including melatonin. Melatonin is important in the regulation of sleep.

The pineal gland is super important because of its impact on hormone regulation. While more research needs to verify its exact function, the information we do have is vital in understanding our minds and bodies.

Where Is The Pineal Gland Located?

The pineal gland can be located in the brain's center and sits in a groove above the thalamus (the part that coordinates sensory functions).

It is made up of neurons, neuroglial cells, and pinealocytes. The pinealocytes are the part believed to create and secrete melatonin into the cerebrospinal fluid.

Cerebrospinal fluid flows around the hollow areas in the brain and the spinal cord, where melatonin is absorbed into the bloodstream. (Cleveland Clinic)

The pineal gland is a cone-shaped gland that is around 0.8 centimeters long and weighs about 0.1 grams. 

All About The Pineal Gland

The pineal gland is one of the twelve glands that form part of the endocrine system.

The pineal gland plays a really vital role in regulating our sleep patterns by receiving and conveying information about the current light-dark cycle from the environment.

During the dark cycle or nighttime, the pineal gland produces and secretes melatonin.

A few retinal ganglion cells in the eye contain melanopsin, a class of photoreceptors, and have the ability to send neural signals to non-image-forming areas of the brain – one of these areas include the pineal gland.

More often, the pineal gland is triggered by photic information from the retina receiving light signals, which inhibits the production of melatonin and causes wake signals. (National Library of Medicine)

Melatonin levels often peak at night, with them being almost 10 times higher than the daytime concentrations.

Additionally, melatonin also has a seasonal (or circannual) rhythm, with higher levels in the autumn and winter when nights are longer, compared to spring and summer.

Alongside melatonin production, the pineal gland also regulates female hormone levels that may impact a woman's fertility and menstrual cycle.

In a 2016 study, researchers also suggested that melatonin could contribute to protection against cardiovascular ailments such as atherosclerosis and hypertension.

So a pretty important gland for sleeping and possibly for other common disorders.

Let us look into how the pineal gland and melatonin production impacts the rest of your body.

The Pineal Gland And Melatonin Production

If you are medically diagnosed with a sleep disorder, it is very likely that your pineal gland is not producing and secreting the right amount of melatonin.

Certain alternative medicine practitioners believe you can activate your pineal gland by detoxing and opening up your third eye, but no scientific research supports these claims.

A way to control melatonin production in your body is by utilizing supplements that will typically make you feel tired but realign your circadian rhythm.

These supplements can also help you to fall asleep faster if you're jet-lagged or experience insomnia. 

In most, low-dose melatonin supplements are effective and safe to use in the short and long term.

These doses can range from 0.2 to 20 milligrams – but your doctor will prescribe the correct dose.

Melatonin supplements could result in the following side effects:

  • Drowsiness and sleepiness
  • Grogginess
  • Extremely vivid dreams
  • A slight increase in blood pressure
  • A moderate drop in body temperature
  • Anxiety and confusion

In the case that you are attempting to become pregnant, are pregnant, or are nursing, you should consult your doctor before using melatonin supplements.

Melatonin is also reported to interact with medications in these groups:

  • Fluvoxamine
  • Nifedipine
  • Birth control pills
  • Blood thinners
  • Diabetes medications
  • Immunosuppressants

If you are using medication in any of these categories, you should consult your doctor before using melatonin supplements. (Healthline)

Cardiovascular Health And The Pineal Gland

A 2016 literature review analyzed past research to determine if melatonin was connected to cardiovascular health.

They found evidence suggesting that melatonin produced by the pineal gland can positively impact one's heart and blood pressure – but more evidence is required to support this belief.

The same review suggested that melatonin significantly affects lipid metabolism and is an inexpensive and well-tolerated drug – which is fantastic for developing countries facing health problems of this caliber.

This paper also suggests that the pineal gland is a neuroendocrine gland that is closely related to human aging.

It is believed that melatonin is an indole neuroendocrine hormone that is secreted by the pineal gland – making it a vital hormone for maintaining physiological function in anti-aging-related cardiovascular diseases.

The Effect Of Melatonin On Female Hormones

Some sources suggest that light exposure to melatonin could aid in menstruation-related issues like mood changes, infertility, and pregnancy complications.

If a woman has reduced amounts of melatonin, they may also experience irregular menstrual cycles – but these studies are limited and often dated, which means new research is needed.

This study also looks at how melatonin affects the female reproductive system, its participation in the aging process, and the formation of pathological menopause.

Other studies have also looked at how melatonin production can help women facing estrogen deficiencies in their postmenopausal years – mainly the cause of increased appetite and related increase in weight.

They suggest that women who face these problems use melatonin supplements to treat these disorders.

The Effect Of The Pineal Gland On Mood Stabilization

It has been indicated that the size of your pineal gland could put you at risk for certain mood disorders – specifically if it's smaller.

This study indicates that if you have a smaller pineal gland, you have an increased risk of developing schizophrenia and related mood disorders.

Another study found that the size of the pineal gland does not contribute to mood disorders but rather the volume of melatonin secreted by the pineal gland.

They found that abnormal melatonin secretion is present in patients with major depressive disorders and bipolar disorders.

While both these studies are preliminary research into something significant for the world of mental health, they are a wonderful stepping stone to developing technologies that could become a reliable indicator for identifying and treating these mood disorders.

The Pineal Gland And Cancer

Similar to mood disorders, some research suggests that there could be a connection between impaired pineal gland functioning and one's risk for cancer.

Recent studies on rats found that lowering pineal gland function through overexposure to light resulted in increased cell damage and an increased risk for colon cancer.

Other studies found that when used with traditional treatments, melatonin could improve the outlook in people with cancer – especially those with more advanced tumors.

A study into the epigenetic approach to malignant tumors found that melatonin doesn't directly inhibit tumor growth but is beneficial in overcoming sleep disturbances.

Better sleep fosters the endorphin system to lead a better quality of life which facilitates the mobilization of defense mechanisms.

However, more research is required into cancer and the effect of the pineal gland to establish how melatonin affects tumors and which dosages would be appropriate as a complementary treatment.

What Happens When The Pineal Gland Malfunctions?

The pineal gland is located around other super important structures and interacts quite actively with blood and other bodily fluids.

If the pineal gland becomes impaired, it can lead to a few problems, including (but not limited to):

  • Hormone imbalances
  • Disrupted sleep or insomnia
  • Female fertility and menstrual cycle

Pineal gland tumors are also problematic, and early signs of a tumor can include:

  • Seizures
  • Headaches
  • Nausea
  • Damage to your vision or other senses
  • Memory disruption

None of these are desirable, so talk to your doctor if you're experiencing any of these symptoms and ask about melatonin supplementation.

Conditions That Affect The Pineal Gland

Experiencing any problems with the pineal gland is highly problematic, but so are conditions that affect it.

The pineal gland's function can be affected by some of the following diseases and conditions:

Pineal Gland Tumors

Tumors of this nature are extremely rare, but there are several types, and these tumors are more likely to affect children and adults under the age of 40.

Pineal gland tumors aren't always cancerous but are problematic in that they press against other parts of the brain, which can block the normal flow of cerebrospinal fluid.

When there is an abnormal flow, the pressure inside the skull increases significantly and requires immediate treatment.

Injury To The Pineal Gland

The position of the pineal gland makes it a challenge to injure.

Still, approximately 30% to 50% of people who experience traumatic brain injury will experience a problem with at least one endocrine gland in their brain.

This kind of injury can happen when people experience:

  • A blow to the head
  • Gunshot wounds
  • Car accidents
  • Concussions

Out of these four, concussions are the most common type of traumatic brain injury. In fact, the CDC reports that there are about 3.8 million recorded sports-related concussions per year in the US alone.

That's not including non-sport-related concussions on an international scale.

Calcification Of The Pineal Gland

Pineal gland calcification is quite common – so much so that healthcare providers often use a calcified pineal gland as a landmark on x-rays to identify brain structures.

Calcification occurs as a result of calcium buildup in bodily tissues, which causes the tissue to harden.

It is somewhat natural for the pineal gland to calcify as you age, but excessive calcification can inhibit the pineal gland from functioning properly.

In some studies, it has been determined that people who are affected by Alzheimer's are more likely to have a higher degree of calcification.

It has also been indicated that there could be a correlation between a calcified pineal gland and frequent experiences of migraines and cluster headaches.

As with most parts of the brain, more studies need to be conducted to determine the exact effects that pineal gland calcification could have on the brain and the body.

Tests To Check Pineal Gland Health

Pineal gland issues are quite problematic – and can sometimes be super difficult to identify.

So, how can you ensure that your pineal gland stays healthy and verify that you don't have any possible underlying issues?

You can start by going to your local healthcare provider and telling them what side effects you've been experiencing.

They are likely to start by checking your melatonin levels through blood tests.

Depending on their analysis, they will then conduct a magnetic resonance imaging scan (also known as an MRI) or a computed tomography (or CT) scan.

These images will help them determine if you have any pineal gland tumors or cysts.

They can also use X-ray scans to see if you are experiencing pineal gland calcification and determine if the amount of calcification is normal.

To keep your pineal gland healthy, you want to look into reducing fluoride consumption and talk to your doctor or a dietician about following a diet that improves pineal gland function and reduces calcification.

How Can Pineal Gland Conditions Be Treated?

The only condition that you can effectively treat without melatonin supplements is a pineal glandtumor or cyst.

Healthcare providers are likely to utilize one or more of these therapies:

  • Surgery
  • Radiation therapy
  • Chemotherapy

You can also keep your pineal gland healthy by creating an environment that promotes healthy pineal gland functioning by getting enough good-quality sleep every night and reducing your amount of blue-light exposure.


While researchers do not fully understand the pineal gland and related melatonin production, we do know that it plays a vital role in sleeping – specifically sleep and wake cycles.

Other research suggests that it plays a vital role in mood disorders and regulation of the menstrual cycle – which could greatly impact how medicine and treatments develop in the future.

It has been found that melatonin supplements could be helpful in managing sleep disorders – but it is always wise to consult with a general practitioner before using these supplements.





Reference this article:

Practical Psychology. (2022, August). What does the Pineal Gland do?. Retrieved from https://practicalpie.com/what-does-the-pineal-gland-do/.

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