The Importance of Melatonin and The Repair Cycle

Executive Summary

  • Melatonin is known as the sleep supplement or hormone, however, it has a critical role in the body’s repair cycle.


Melatonin is normally discussed in terms of helping people get to sleep. This is the primary reason most people take melatonin. However, there is a lesser-discussed feature of melatonin with respect to body repair that will be illuminated in this article.

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The Relationship Between Sleep and Repair

Melatonin tells the body to get ready for sleep, and also to repair the body. Sleep is the time where the body can switch from performing activities to repair. During sleep, there are few demands on the body and few stresses. This is explained in some of the following quotes.

During sleep, a higher level of collagen is released into the body. Collagen proteins help strengthen skin cells and repair those that are damaged. This is important for the healing process. As a side benefit, collagen reduces wrinkles and helps skin look younger.

During the day as you rush to work, head to the gym in the afternoon and get a few chores done before bed, your muscles are working hard and burning energy. Your body releases adrenaline, cortisol and other hormones to meet the energy demands. When you fall asleep, these hormone levels decrease and different beneficial hormones including the human growth hormone are released, which help with muscle repair, growth and general maintenance.

Your body is busy with all your life tasks from walking to working all day long. When you head to bed, your body turns attention to the immune system. Proteins, white blood cells and other substances are sent out to fight off germs, infection and disease. Lack of sleep can actually decrease your resistance to infection and disease because this immune system boost is not able to be completed. Increasing your sleep when you are fighting disease or infection allows your immune system more time to do its work and helps with recovery. – Whitehall

Immunocompromised During the Day?

This quote explains that one is essentially “immunocompromised” during the day. This is because the immune system cannot work at full capacity while one is awake as the body can be viewed as in its production mode.

This is generally not very well explained, as one is normally taught to think of the immune system as just a general defense system that is always functioning. This quote above illustrates the strong connection between melatonin and immunity. Melatonin is also connected to human growth hormone or HGH. HGH also increases during sleep, again to promote repairs.

Repair happens disproportionately when we sleep.

Therefore, rather than viewing sleep as a passive activity (which is how most people look at it), it is more accurate to view it as active. We are not conscious of course, which is a major reason that we underestimate its importance (how can something be so important if the body prefers us to be unconscious?) but our body and brain are very active. Just our consciousness is not and our body is not active in that it is not moving around. It is most accurate to consider the period of sleep as one of the most critical to one’s health. This means not only getting a lot of sleep, but also providing a good sleep environment, regulating the timing of sleep, and providing the best nutrients to the body so it can take advantage of the time of sleep. This last part is nearly entirely ignored by the population and in much of the available information on the topic.

Melatonin and Immunomodulation

As I cover in the article The Cover Up by the Medical Establishment on Vitamin D Levels, vitamin D is an immunomodulatory. This means it keeps the immune system in healthy range, neither overreacting and attacking non foreign entites (auto immune disorders) or underreacting (poor immune response). Melatonin is another immunomodulator, as is explained in the following quotation.

Taking a synthetic supplemental form of that hormone might help people who aren’t producing the hormone naturally because of age, one of several health disorders, or because they’re trying to go to bed at a different time than usual. But it’s less likely to help in most other circumstances and could cause side effects like next-day drowsiness.

Melatonin and Wound Repair

Melatonin helps us do general repair, however, it should not be surprising that it improves more serious types of repair.

The following quote describes this relationship and illustrates the influence of melatonin as wound repair.

We propose that melatonin is an ideal candidate to enhance the process of wound healing. The present study assessed the effects of exogenously administered melatonin (1.2 mg/kg intra-dermal), on scar formation using a full-thickness incisional rat model of dermal wound healing. Melatonin treatment significantly improved the quality of scarring, both in terms of maturity and orientation of collagen fibres. – PubMed

Melatonin also enhances the repair of skeletal muscle.

Melatonin is a highly evolutionary-conserved ancient molecule that was only recently rediscovered as a safe dietary supplement in muscle disorders and in exercise. This review attempts to shed light on potential and promising therapeutic roles of melatonin to limit muscle deterioration, mainly mitochondrial function, and sarcopenia. – NCBI

And this quote shows the benefits to overall body composition improvement.

The participants who had been supplemented with melatonin showed decreased fat mass by 7% compared to the placebo group. They were also able to increase lean mass by 2.9% compared to the placebo participants. Additionally, adiponectin levels increased significantly (by 21%) in the melatonin group.

The participants who had been supplemented with melatonin showed decreased fat mass by 7% compared to the placebo group. They were also able to increase lean mass by 2.9% compared to the placebo participants. Additionally, adiponectin levels increased significantly (by 21%) in the melatonin group.

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).

The results of the study suggested that:

Athletes who were supplementing with melatonin showed an increase in total antioxidant capacity for muscle protection compared to the placebo group.

Melatonin supplementation appeared to prevent the increase of chemical toxins created during oxidative stress compared to the placebo group.

Participants taking melatonin had reduced levels of harmful chemicals, which indicated they experienced less exercise-induced muscle damage from oxidative stress compared to the placebo group.

The melatonin group maintained a higher ratio of protective enzymes that help preserve muscle tissue compared to the placebo group.

Total cholesterol levels were reduced in the melatonin group compared to the placebo.

Though this was a small trial, the researchers concluded that melatonin was beneficial to resistance-trained athletes. Melatonin might help prevent exercise-induced oxidative stress and could offer muscle tissue protection against oxidative damage. – VeryWellFit

Melatonin and Cancer

Before I performed the research I had never heard of a relationship between melatonin and cancer prevention or treatment.

I found the following quotes on this topic.

Melatonin has been shown to play a fundamental part in neuro immune modulation. Besides regulating the circadian rhythm it works as a natural antioxidant with immune stimulatory and anti-cancer properties. Melatonin is a regulator of hemopoiesis and modifies various cells and cytokines of the immune system. Melatonin elicits oncostatic properties in a variety of different tumor cells. A number of studies have documented that melatonin, given in combination with chemotherapy to patients with disseminated disease, increases the overall survival and reduces toxic side effects.

The last decade has shown an increasing interest in melatonin, a pleiotrophic molecule, which functions as sleep regulator, immune stimulant, antioxidant, is a modulator of apoptosis and has oncostatic properties [5-8]. Thus, women who work with night shifwork, and therefore exposed to light at night, have a suppressed level of melatonin and at the same time an increased risk of developing breast cancer [9].

Melatonin significantly improves complete and partial remission as well as the one-year survival rate by around
50% [10]. These effects probably reflect the pleiotropic functions of melatonin as an immune stimulant and its protection from chemotherapeutic-induced bone marrow suppression, the increased efficacy of chemotherapy, reduce cellular immune levels of oxidative stress [13] as well as the oncostatic and anti-proliferative properties of melatonin [8] (Figure 1).

Melatonin displays low toxicity with no serious side effects
reported with doses as high as 20 mg/day [10-12].

Melatonin protects CD4+ T-lymphocytes [20] and monocytes
[21] from apoptosis. This effect seems to be mediated by a protection of the mitochondria and activation of intracellular signal pathways [21].

The influence of melatonin on infectious and autoimmune
diseases has been the focus for a number of studies. These studies show that melatonin administration can be beneficial for patients with infectious diseases by shorting disease duration and improve clinical outcome [6,22]. When it comes to melatonin and autoimmune diseases, the results are few and contradictory [6,22]. Here more research is required, and it is possible that melatonin might not be beneficial in this area.

Melatonin definitely seems to improve overall survival and increase the rate of both partial remissions in cancer patients treated with chemotherapy and in patients in palliative care. Furthermore, the studies show that
melatonin administration reduces the toxic side effects of radio- and chemotherapy on the bone marrow reducing lymphocytopenia, thrombocytopenia and anaemia. At the same time there has been reported a protective effects towards neurotoxicity, cardiotoxicity, fatigue and neoplastic cachexia [10-13,22,30]. – Clin Med Journal

One question might be is if any of this is specific to cancer, or if it melatonin simply improves the functioning of the immune system. I bring up this same issue Why Are Some Supplements Treatments for Covid with respect to the melatonin improving the response versus the immune system.

The Impacts of Aging on Melatonin Production

As we age, our melatonin production declines. This means we sleep less well, and this means that we repair ourselves less well. Many health websites treat melatonin as an unnecessary supplement. However, on the other hand, they acknowledge both the increase in sleep problems as people age and the fact that the body creates less melatonin as we age. This seems like a strange position to hold that melatonin supplementation may not be necessary particularly for older individuals.

Melatonin Versus Cortisol

Cortisol is the stress hormone and stops the body from repairing itself. Cortisol rises to unhealthy levels when we over-exercise or experience high levels of stress. Melatonin blocks the effect of too much cortisol production.

This is another reason that melatonin is so good prior to sleep. If a person has higher cortisol levels, they will not repair themselves as well.

Melatonin and Artificial Light

Humans evolved without all of the artificial lights that we have today. For this reason, it was much easier for the body to begin producing melatonin earlier, as melatonin production in part is modulated by light. In the past, the light level decline when the sun went down. However, that is no longer the case. Anyone who uses a computer or other lit screen is further reducing their melatonin production.

The Relationship Between Melatonin and Vitamin D

Vitamin D is the signal to the body that it is not winter, and to not be parsimonious with the repair work. Melatonin gets the body into the state of optimal repair. This is the relationship between these two supplements and a relationship that I do not see written about much, however, it is obvious. One might say that this relationship is less well-proven.

I put the relationship together through understanding how each of these items works. And as I showed in the article Why Are Some Supplements Treatments for Covid, it is very rare that I see a relationship like this, and that relationship later proves to be invalid.

WebMD on Melatonin

WebMD had an article on melatonin that was far more negative than my experiences taking melatonin. See the following quotes from this WebMD article.

One review of 15 studies involving 284 subjects found that those who took melatonin before bed fell asleep 3.9 minutes faster on average and slept 13 minutes longer. Another, of 19 studies involving 1,700 people, found melatonin users fell asleep 7 minutes faster on average and slept 8 minutes longer.

The dosage is not listed. However, one of the strategies of the medical establishment is to use very low doses of the supplement and then say that there is little effect. Here is another good example of this under dosage.

For instance, start with 0.5 mg (500 micrograms) or 1 mg 30 minutes before going to bed. If that does not seem to help you fall asleep, try increasing your dose to 3–5 mg. – Healhline

I have never heard of a dose of .05 MG.

.05 MG is so low, it is difficult to find a supplement pill of that size. The minimum pill size for melatonin is normally 3 GM, or 6x .05 MG.

This might be because the naturally produced level of melatonin is actually less than this as is explained in the following quotation.

Most studies begin with a conservative dose (less than 0.3 mg per day)—which is close to what our body produces naturally. – VeryWellFit

The idea that someone should start at .05 MG of melatonin is curious. Yes, I understand it is higher than the average internal production, but supplements are always higher than this.

The following claim is also ridiculous.

Taking more melatonin than this likely will not help you fall asleep faster. The goal is to find the lowest dose that’ll help you fall asleep. – Healhline

That would be true if melatonin had widely reported side effects, but it doesn’t. The following quote by Healthline addresses this issue of potential side effects.

That being said, some people may experience mild side effects, such as:

nausea – Healhline

And these side effects…

Disruption of circadian rhythms if too much is taken
Drowsiness if taken during the day
Drowsiness upon waking if too much is taken the night before
Vivid dreams or nightmares
Some people report additional side effects, such as stomach cramps, dizziness, headache, irritability, reduced libido, and reduced sperm count in men. – VeryWellFit

However, I do not agree that these are widespread side effects. The following quote also claims side effects from Melatonin.

Taking a synthetic supplemental form of that hormone might help people who aren’t producing the hormone naturally because of age, one of several health disorders, or because they’re trying to go to bed at a different time than usual. But it’s less likely to help in most other circumstances and could cause side effects like next-day drowsiness. – Consumer Reports

First, that quote is bizarre, as it is known that melatonin production drops with age. And everyone ages.

Even at 30 MG of melatonin per night, I have never had any side effects, (although I did not measure my sperm count before and after) and obviously, this is a much higher dosage than anything described in Healthline.

In fact, Jeff T Bowles recommends even higher levels of melatonin supplementation than this. Either I have a bizarrely high tolerance level of melatonin supplementation, or these side effects are being exaggerated.

Here are several low dosages of melatonin studies that purport to show that taking melatonin will not reduce one’s own internal melatonin production.

A physiological dose of melatonin (0.5 mg) or placebo was given at bedtime to night shift workers (n = 21) for seven days, and endogenous melatonin profiles were measured on the eighth day. The amplitude of endogenous melatonin secretion was unchanged by treatment. Also, a melatonin treatment trial using a 50 mg daily bedtime dose for 37 days to a blind subject resulted in no change in the endogenous melatonin profile. We conclude that circulating melatonin can shift the phase, but does not alter the amplitude, of pineal melatonin secretion. – PubMed

And then this study.

The aim of this study was to assess further the entraining effects of a daily dose of 0.5 mg melatonin on the
cortisol rhythm and its acute effects on subjective sleep in blind subjects with free-running 6-sulphatoxymelatonin (aMT6s) rhythms (circadian period [τ] 24.23-24.95 h). Ten subjects (9 males) were studied, aged 32 to 65 years, with no
conscious light perception (NPL). In a placebo-controlled, single-blind design, subjects received 0.5 mg melatonin or placebo p.o. daily at 2100 h (treatment duration 26-81 days depending on individuals’ circadian period). – SagePub

I have to ask why such a low dosage was used in these studies. This is normal, however. The dosages are set low so that the result or impact of the effect is low.

How Melatonin Reduces the Need for Drug Sleep Aids

Something left out of any of the articles I read that listed the concerns with the potential side effects of melatonin, is that melatonin can replace drug sleep aids.

I know something about this as melatonin eliminated my need for relying on an anti-histamine, which I had been doing to bring about sleep on some nights. There is little doubt that melatonin has far fewer side effects than an anti-histamine. If I take a full anti-histamine dose, or pill, I feel “rubbery” the next day. This is why I limit myself to 1/2 or 1/3 of an anti-histamine pill.

However, I have taken up to 40 MG of melatonin and I have never felt any side effects.

Furthermore, the WebMD article entirely left out the other positive aspects of melatonin. This is not true of the more general health websites that I have quoted above, but it is true of WebMD.

All of this makes it appear that establishment medical sources are deliberately undermining natural supplements like melatonin. Furthermore, the claim made by WebMD that there may be safety concerns is just not believable. WebMD does not do the math of comparing the risks of drugs, which are far far higher as I cover in the article A Calculation of the Relative Risks of Pharmaceuticals Versus Nutrition Supplements.

Do We Really Need More Studies to Endorse Melatonin Supplementation?

The WebMD articles and other articles repeatedly state that more studies are necessary to prove melatonin’s safety, however, melatonin is one of the more widely taken supplements. I am taking large doses of melatonin as are others that follow the advice of Jeff T Bowles. You can see people commenting on Jeff T Bowles website on the topic of melatonin. People are not complaining about side effects from taking high dosages of melatonin.

We live in a health information environment where we are warned against the dangers of something like melatonin or vitamin D but then told to take covid vaccines, which as I cover in the article How Safe Are Covid Vaccines, are bad for our immune system. However, before I was vaccinated, I don’t recall these health sources warning me about the vaccines.

As I cover in the previous article link, on risk calculation, the math of the medical establishment does not add up. They will hide and accept high-risk treatments if they are drugs, but then change the threshold to ridiculous levels when the topic changes to natural supplements.

The Lack of Integrated View of Melatonin

There are a lot of independent observations regarding melatonin’s benefits. However, there is certainly a lack of an integrated view of these benefits.

For example, the first problem is that melatonin is presented as primarily for initiating sleep. This is why I first took melatonin supplements years ago. However, the more one investigates the topic, the more connections melatonin has to different things. Melatonin is intertwined with the immune system, and is an immunomodulator. At least one reason is that melatonin, sleep, and immunity are all connected to each other. Yet I have never heard of melatonin recommended for those with auto immune disorders. In fact, the Mayo Clinic recommends against it as you can see in the following quotation.

Don’t use melatonin if you have an autoimmune disease. – Mayo Clinic


Why not? The Mayo Clinic does not explain.

However, I did find the explanation on the LiveStrong website.

Despite melatonin’s antioxidant properties, it has demonstrated a tendency to stimulate inflammation in people with certain autoimmune disorders. A study published in the October 2007 issue of the “British Journal of Clinical Pharmacology” demonstrated that rheumatoid arthritis actually worsened in study subjects who took melatonin. This finding surprised and disappointed the study’s authors, who thought supplemental melatonin might benefit people with autoimmune diseases. However, these results mirror more recent research published in May 2014 in the “Journal of Immunology Research,” which confirms that high levels of melatonin seem to worsen rheumatoid arthritis by stimulating immune cells to release inflammatory cytokines. – LiveStrong

That is a bizarre result, as melatonin has the opposite effect on the immune system.