The Unspoken Truth about Melatonin
Melatonin is well known for its attributes to enhancing the quality of sleep. It is available for sale in many major department stores and even local bodegas. The dosage amount for melatonin varies from brand to brand. Some claim to deliver 5 milligrams while others provide 10 milligrams over a certain number of hours. Personally, I have worked with the nutrient, conducting experiments to optimize its delivery power. However, there is more to melatonin than simply putting someone to sleep. It can be considered a floater because of its many features in human metabolism. The role it plays in women's reproductive health needs more attention, especially for women battling PCOS.
Plants and humans both produce melatonin, which is a naturally occurring molecule. Among the many sites where this compound is created are the gastrointestinal tract, skin, retina, and lymphocytes (immune cells) to name a few. The mitochondria are responsible for generating this nutrient within the cell. Circulating melatonin is primarily supplied by the pineal gland, the circadian pacemaker, where it is intentionally released into the bloodstream and cerebrospinal fluid. Because light inhibits its secretion, it is produced and emitted at night in response to darkness. Growth hormones and glucocorticoids, for example, are also hormones that act on cellular metabolism with regular rhythmic fluctuations in their action. By rearranging metabolic tissues, melatonin prepares organs for interactions with other circadian-dependent hormones. The following are other attributes of our dear friend melatonin that deserve special attention:
regulates energy consumption
controls energy flow to and from storages
policies glycemia and lipidemia
enhances both central and peripheral insulin action
syncing to the body’s internal rhythm:
skeletal muscle metabolism
white adipose tissue metabolism
hepatic metabolism
Insulin synthesis secretion and action
an antioxidants, stabilizes free radicals by sharing an electron and becoming friends
supports the immune system
oncostatic effects – may help mitigate the spread of a cancer
In this article, we will discuss melatonin's effects on insulin, its role in circadian metabolic processes, which are coordinated with the activity-feeding-resting-fasting cycle, and its role in maintaining an adequate energy balance by regulating energy flow. Melatonin levels and circadian synchronization are intrinsically linked and need to be maintained at appropriate levels.
Check this out: Melatonin regulates energy metabolism during waking and feeding hours by triggering energy intake and storage. Insulin responsiveness is high, indicating that energy is stored in various ways as shown below.
liver: Glycogen synthesis and glycolysis promote the storage of glucose for energy reserves
white adipose tissue: lipogenesis and adiponectin– makes fat cells to store more energy
pancreas – increase insulin in the blood to bring in more glucose into tissues and cells
During times of rest/sleep and fasting, energy expenditure increases. In this state, insulin resistance takes precedence. The following course of action takes place:
Liver: the breakdown of glycogen, the energy reserve to supply energy to needed cells and organs
white adipose tissue – the breakdown of fat cells to create ATP
pancreas - Glucagon are emitted to increase their levels to help breakdown glycogen to tap into the energy reserves
When melatonin levels are low or absent, energy metabolism no longer functions optimally. During waking hours, insulin resistance takes precedence while in the fasting state, insulin sensitivity is high. This encourages weight gain eventually leading to obesity. The browning of white adipose tissue is caused by this molecule at adequate levels, meaning many calories are used up in the process of making heat. It is through the transition from white to brown adipose tissue that glucose and fatty acids are converted into energy and fat is prevented from being stored as fat. In the end this reaction helps control body weight. Factors that can contribute to the absence and reduction of melatonin are the following:
aging
graveyard shifts
illuminated environments during the night – using a cellphone late at night
induced insulin resistance
glucose intolerance
sleep disturbance
obesity
metabolic disease
In terms of female reproductive health, our friend melatonin has some cool effects. One of the major causes of female reproductive system problems like infertility is oxidative stress. Seeing as melatonin is a potential free radical scavenger, it aids in defending oocytes and eggs from oxidative stress, specifically during ovulation. This mechanism also protects the developing fetus from oxidative stress. There tends to be more melatonin in the follicular fluid than there is in the bloodstream. During follicle maturation, melatonin concentrations rise. Tests can be done on urine samples to determine melatonin levels by measuring 6-sulfatoxymelatonin, the most relevant metabolite. It's a reliable indicator of how much melatonin the body produces. Melatonin emissions can be controlled by testosterone and estrogen.
The situation is different for women with PCOS. Melatonin levels in the follicular fluid of PCOS women are particularly low compared to healthy women with PCOS. Gonadotropin secretion is altered by melatonin deficiency, resulting in reduced FSH levels and high LH levels. This further contributes to PCOS's sick cycle due to excessive LH production. When there's not enough melatonin, the hypothalamic axis becomes blocked, and cystic follicles start to die. PCOS women have higher levels of 6-sulfatoxymelatonin concentration compared to their counterparts. It could mean the body is producing melatonin but not utilizing a lot of it. Additionally, the issues mentioned earlier can also affect women without PCOS.
The benefits of melatonin as a whole should not be underestimated. An adequate amount of it in the body is necessary for it to function properly. Nutrition and dietary supplements may have a positive effect, but other variables must be incorporated into the intervention plan to see improvement. Stress management, regular physical activity, getting quality sleep, and staying on top of your health are examples. Consider these other benefits of melatonin gummies next time you pop one in before heading to sleep. On that note, let’s pause and enjoy the rest of the day. As always, Stay Strong & Stay Vivid!
References
Mojaverrostami, D.V.M., et, al. (2019). The role of melatonin in polycystic ovary syndrome: A review. International Journal of Reproductive BioMedicine. https://doi.org/10.18502/ijrm.v17i12.5789.
Cipolla-Neto, J. et al. (2014). Melatonin, energy metabolism and obesity: a review. Journal of Pineal Research. https://doi.org/10.1111/jpi.12137.
