Highlighting the importance of circadian cycles in metabolic diseases, obesity, and cardiovascular and neurodegenerative conditions. Exposure to light—especially artificial light at night—can modulate and disrupt the balance of leptin and ghrelin levels in adults. This affects appetite regulation and metabolism, leading to increased caloric intake and contributing to issues such as obesity. Sleep deprivation disrupts the circadian rhythm and hormone production, resulting in a decrease in leptin (the satiety hormone) and an increase in ghrelin (the hunger hormone), which drives a greater craving for high-calorie foods.
An alteration of the biological clock has been observed in obesity, leading to an increase in the expression of inflammatory cytokines—a process further exacerbated by the condition itself. Furthermore, the disruption of the circadian rhythm may contribute to metabolic dysfunction in adipose tissue, thereby increasing the risk of developing cardiometabolic diseases.
The interplay between the circadian rhythm and cancer involves the regulation of cell division, DNA repair, immune function, and hormonal balance, as well as the potential for chronotherapy. Circadian rhythm disruptions can promote abnormal cell development and tumor metastasis, potentially due to immune system imbalances and hormonal fluctuations.
Dysfunction of the 24-hour circadian rhythm is a common occurrence in older adults; it is particularly severe in individuals with age-related neurodegenerative diseases, including dementias associated with Alzheimer’s disease and Parkinson’s disease. The manifestations vary depending on the type and severity of the neurodegenerative condition and, in some patients, may appear even before the onset of the typical clinical symptoms of neurodegeneration.
Thank you for your excellent report on the retina and the importance of circadian cycles. Experience is the mother of science, and a reflective journey through life is fundamental to health. The retina does more than just allow us to see; it also plays a crucial role in regulating our biological clock. It contains photosensitive ganglion cells that hold melanopsin and transmit light-related information to the suprachiasmatic nucleus of the hypothalamus—our primary control center for circadian rhythms. Time is an essential, though often underestimated, determinant of human physiology and disease. The circadian clock—a genetic synchronization system—coordinates transcriptional and signaling networks within tissues to maintain homeostasis. Recent discoveries have refined our understanding of this system, shifting the model from a linear transcription-translation feedback loop to a distributed, dynamically coupled network that integrates environmental signals with physiological processes. Genetic variation in core circadian genes and circadian misalignment are now recognized as key modifiers of disease risk.
While circadian regulation is best known for controlling the sleep-wake cycle, growing evidence demonstrates that peripheral clocks exert critical control over organ-specific physiology. The lung, for instance, is a highly rhythmic tissue in which local circadian oscillators coordinate airway tone, immune surveillance, inflammatory signaling, epithelial repair, and metabolic homeostasis. Disruption of the circadian rhythm—stemming from genetic alterations, environmental stressors, shift work, irregular light exposure, or chronic inflammation—has emerged as a significant factor in the development and progression of various respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, acute lung injury, sleep-related breathing disorders, and lung cancer.
The circadian system is a key regulator of cardiovascular and immune homeostasis. Emerging evidence suggests that the daily synchronization of immune responses can influence the progression of cardiovascular disease by coordinating leukocyte trafficking and inflammatory thresholds. Circadian rhythms, governed by the body’s endogenous clock mechanism, regulate daily fluctuations in cardiovascular function, optimizing physiological processes such as blood pressure regulation, cardiac metabolism, and myocardial repair. These rhythms also align cardiovascular reactivity with predictable environmental and behavioral cycles, facilitating normal function and influencing susceptibility to disease. Major adverse cardiovascular events—such as myocardial infarction, ventricular arrhythmias, and stroke—exhibit a distinct morning peak, underscoring the role of circadian regulation in cardiovascular health. Altering patterns of light exposure can disrupt circadian rhythms, leading to impaired reproductive function.
Natural light, particularly that received during the morning, helps synchronize the sleep-wake cycle, melatonin secretion, and other physiological rhythms. Conversely, exposure to intense light at night—especially light containing short wavelengths—can delay the circadian clock and disrupt sleep.
1) Melanopsin and photosensitive retinal ganglion cells — Nature (2002). A foundational piece of work for understanding how the eye detects light, with functions that extend beyond vision. https://www.nature.com/articles/415493a
Sleep, exercise in nature, and the consumption of raw fruits and vegetables—rich in a variety of colors, biophotons, enzymes, and phytochemicals—form a solid foundation for health. Circadian rhythms are endogenous biological cycles that regulate essential cardiovascular functions, such as blood pressure, heart rate, vascular tone, and metabolic homeostasis. The disruption of these rhythms—caused by factors such as shift work, exposure to artificial light at night, irregular sleep-wake cycles, or eating at inappropriate times—is increasingly recognized as an independent risk factor for cardiovascular disease. A growing body of research links circadian misalignment to key pathophysiological mechanisms, including endothelial dysfunction, oxidative stress, inflammation, and autonomic imbalance. Melatonin, a hormone produced primarily by the pineal gland, plays a fundamental role in circadian regulation and possesses potent antioxidant, anti-inflammatory, and cardiometabolic properties.
Maintaining a healthy circadian rhythm requires a consistent sleep schedule, regular exposure to light, and daily physical exercise. The use of artificial light in our homes and the prevalence of electronic devices have led more people to report shorter sleep duration and irregular sleep patterns. During sleep, our cells utilize this rest period to repair damaged structures and regenerate new cells following apoptosis.
The CLOCK (Circadian Locomotor Output Cycles Kaput) gene is a core component of the circadian clock and serves as a primary regulator of circadian rhythms, mediating various biological processes. Consequently, abnormal expression of CLOCK impairs its role within the circadian clock, as well as its broader function as a direct regulator of gene expression. Cortisol is a promising biomarker for detecting early signs of circadian rhythm disruption induced by stress. Early detection of a subpathological alteration in the circadian rhythm could point to a reversible state, offering an opportunity to preserve health.
It has been shown that circadian rhythm disruption is associated with an increased risk of developing obesity and obesity-related diseases, and is closely linked to tumorigenesis in cancer.
Emerging evidence suggests that exercise—a potent modulator of muscular adaptation—can also influence circadian regulation, providing a potential avenue for improving muscle repair in older populations.
Dysfunction of the 24-hour circadian rhythm is a common occurrence in older adults and tends to be more severe in individuals with age-related neurodegenerative diseases. The provided links are for those interested in further exploring the topic. https://www.tandfonline.com/doi/abs/10.1080/13813455.2021.1988110 (2024).--
I have had floaters for as long as I can remember. Yes, I also had bad reactions to vaccines, grew up on a main road, in a major city, when leaded petrol was the go, ate some crappy food, had loads of wheat & dairy but didn't know I was Coeliac and allergic to dairy etc. No wonder I had floaters! Such a toxic load I carried...
I remember telling the Optometrist in my late teens/early 20s that I noticed more floaters when I was tired. He found that odd. But did not offer an explanation, other than floaters were proteins 'floating' about in the eye. In other words, he did not know why I should find them higher in number & more noticeable when I was tired. Nor did he tell me WHY I might have extra proteins floating about in my eye. Your article finally explained things to me. Thankyou!
But you know, Schneider might be onto something. If I shake my eyes about behind the eyelids (bright light not required, though!), the floaters DO move! They are most definitely mobile in the vitreous humour.
I'm in my late 40s now, and I have LESS floaters than 30 years ago! So much for being an age-related problem. As you rightly pointed out, it's a "correlation with duration of exposure
rather than with age itself." Perhaps I have far less floaters these days because I've been taking much better care of my health for many years, now.
However, I've noticed a few more floaters in recent times - since they've done heaps of chemtrails spraying around my area (Northern Rivers in NSW) INCLUDING FROM A C17 ARMY PLANE DROPPING THEM THE OTHER DAY, in tandem with the usual suspects (little white planes). Just in case you're wondering if the government is trying to poison and kill you, the answer is an unequivocal YES. Doesn't that make you feel better when you pay your taxes?
Anyway, we're now at the point where we keep the ball valve partially OPEN to let the water out before it makes it to the water tanks, and only close it when we want to save water that we know is clean, after all the sprayed chemicals have rained down! The water runs clear and stops smelling funky. You can also tell the difference in the air. I also get an itchy nose and cough again when they're spraying. Plus the air is often a bit frigid, even on warm days. When it's blue sky, it's easy to see if they're spraying. But I have to rely upon my bodily senses when it's all grey, however. Luckily, my body responds very well! So, at least we're avoiding capturing the poisoned water, which will be better for my vitreous humour - but unfortunately, we are all still breathing in those chemicals when THE GOVT does chemtrails.
Back to the eyes, I also think it's shocking that they basically put a blue light filter on the cataract lenses. I mean, sure, I have the blue light filter (night light) switched on on my laptop on all the time, but it's a laptop. My eyes don't want a hideously bright screen, nor do I want it to affect my ability to sleep at night if I'm using the computer late sometimes. But our bodies NEED sunlight! Our eyes need it! It affects so much! I've only ever owned one proper pair of sunglasses. Barely wore them. They always annoyed the bridge of my nose! I played tennis for years in the sun. No sunnies. I like seeing natural light, unfiltered, with my real eyes. I feel alive doing that!
We've been told for so long that the sun is BAD, and we should limit our exposure. Yet another way to get ill! I mean, sure, don't fry yourself in the middle of the day in high Summer, but I am just flabbergasted by how many LIES we have all been told about our health. From the very people we are meant to trust! And maybe that's the problem. We put our trust in others instead of holding onto our self-sovereignty. Instead of believing in ourselves and using our intuition, we willingly hand over our personal power to some nitwits masquerading as doctors with financial gain - at the expense of your health! - in mind. No wonder people are sick!
I have had cataract surgery on one eye. The 4 weeks of eye drops following that was horrific. I had terrible side effects. I haven’t had the other eye done and now finding out about the UV rays being blocked. I’m in no hurry. I spend a lot of time outside most especially early morning. I love to see the sunrise. I understand the circadian clock very well. I sleep very well most nights and sure don’t want to mess that up.
Don't miss the bit about castor oil applied to your eye lids (mention in this essay). Externally applied castor oil has healing benefits mentioned is other essays on unbekoming.
Shift work is associated with a significant increase in cancer risk. In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus houses the "master clock," which synchronizes with the ambient light cycle by directly coordinating efferent and neuroendocrine signals from the autonomic nervous system. Specifically, several proteins involved in the cellular clock mechanism are closely associated with positive and negative transcriptional feedback loops.
Various studies have revealed that shift workers face a higher risk of developing breast and prostate cancer, as evidenced by a strong correlation between long-term shift work (>20 years) and an increased cancer risk. Furthermore, previous research indicates that people in modern society have adopted less-than-healthy lifestyle habits—such as excessive caloric intake around midnight or continuous calorie consumption throughout the 24-hour day—which mimic aspects of shift work and may potentially increase the risk of prostate and breast cancer. The rest/activity rhythm has also been identified as a key factor, given its significant impact on the clinical management of patients with metastatic colorectal cancer (CRC), who often experience poor quality of life characterized by erratic rest/activity patterns.
The dysregulation of sleep-wake cycles, such as prolonged sleep deprivation, disrupts the immune system. Disruptions to normal sleep-wake cycles can lead to abnormal inflammatory responses—demonstrated by the upregulation of pro-inflammatory cytokines (notably IL-6 and CRP)—which serve as potential risk factors for various types of cancer, including ovarian, brain, breast, and colorectal cancer. In particular, hyperphagia and weight gain are closely linked to sleep deprivation; being overweight or obese facilitates increased secretion of adipokines and the release of macrophages from adipose tissue, which triggers chronic inflammation—leading to subsequent oxidative stress and DNA damage—thereby contributing to cancer development. Chronic disruption of sleep-wake cycles can cause greater DNA damage and impair DNA repair, representing a potential risk factor for tumorigenesis.
Highlighting the importance of circadian cycles in metabolic diseases, obesity, and cardiovascular and neurodegenerative conditions. Exposure to light—especially artificial light at night—can modulate and disrupt the balance of leptin and ghrelin levels in adults. This affects appetite regulation and metabolism, leading to increased caloric intake and contributing to issues such as obesity. Sleep deprivation disrupts the circadian rhythm and hormone production, resulting in a decrease in leptin (the satiety hormone) and an increase in ghrelin (the hunger hormone), which drives a greater craving for high-calorie foods.
An alteration of the biological clock has been observed in obesity, leading to an increase in the expression of inflammatory cytokines—a process further exacerbated by the condition itself. Furthermore, the disruption of the circadian rhythm may contribute to metabolic dysfunction in adipose tissue, thereby increasing the risk of developing cardiometabolic diseases.
The interplay between the circadian rhythm and cancer involves the regulation of cell division, DNA repair, immune function, and hormonal balance, as well as the potential for chronotherapy. Circadian rhythm disruptions can promote abnormal cell development and tumor metastasis, potentially due to immune system imbalances and hormonal fluctuations.
Dysfunction of the 24-hour circadian rhythm is a common occurrence in older adults; it is particularly severe in individuals with age-related neurodegenerative diseases, including dementias associated with Alzheimer’s disease and Parkinson’s disease. The manifestations vary depending on the type and severity of the neurodegenerative condition and, in some patients, may appear even before the onset of the typical clinical symptoms of neurodegeneration.
https://www.sleepfoundation.org/circadian-rhythm (2023).----
https://link.springer.com/article/10.1007/s10549-022-06792-0 (2023).---
https://www.sciencedirect.com/science/article/pii/S1044579X23000366 (2023).---
https://undergradsciencejournals.okstate.edu/index.php/MRCMB/article/view/17654 (2023).--
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10069698/ (2023).---
https://www.mdpi.com/2072-6694/15/2/408 (2023).--
https://link.springer.com/chapter/10.1007/978-3-031-63657-8_2 (2024)---
https://link.springer.com/article/10.1007/s13679-025-00610-6 (2025)---
https://www.researchgate.net/profile/Kampala-International-University-Vi/publication/401243161_Circadian_Rhythm_Disruption_Sleep_Disorders_and_Their_Role_in_Obesity-Linked_Diabetes/links/69a016a364ca8a382091f5ec/Circadian-Rhythm-Disruption-Sleep-Disorders-and-Their-Role-in-Obesity-Linked-Diabetes.pdf (2026)---
https://iadns.onlinelibrary.wiley.com/doi/full/10.1002/fsh3.70108 (2026)---
Thank you for your excellent report on the retina and the importance of circadian cycles. Experience is the mother of science, and a reflective journey through life is fundamental to health. The retina does more than just allow us to see; it also plays a crucial role in regulating our biological clock. It contains photosensitive ganglion cells that hold melanopsin and transmit light-related information to the suprachiasmatic nucleus of the hypothalamus—our primary control center for circadian rhythms. Time is an essential, though often underestimated, determinant of human physiology and disease. The circadian clock—a genetic synchronization system—coordinates transcriptional and signaling networks within tissues to maintain homeostasis. Recent discoveries have refined our understanding of this system, shifting the model from a linear transcription-translation feedback loop to a distributed, dynamically coupled network that integrates environmental signals with physiological processes. Genetic variation in core circadian genes and circadian misalignment are now recognized as key modifiers of disease risk.
While circadian regulation is best known for controlling the sleep-wake cycle, growing evidence demonstrates that peripheral clocks exert critical control over organ-specific physiology. The lung, for instance, is a highly rhythmic tissue in which local circadian oscillators coordinate airway tone, immune surveillance, inflammatory signaling, epithelial repair, and metabolic homeostasis. Disruption of the circadian rhythm—stemming from genetic alterations, environmental stressors, shift work, irregular light exposure, or chronic inflammation—has emerged as a significant factor in the development and progression of various respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, acute lung injury, sleep-related breathing disorders, and lung cancer.
The circadian system is a key regulator of cardiovascular and immune homeostasis. Emerging evidence suggests that the daily synchronization of immune responses can influence the progression of cardiovascular disease by coordinating leukocyte trafficking and inflammatory thresholds. Circadian rhythms, governed by the body’s endogenous clock mechanism, regulate daily fluctuations in cardiovascular function, optimizing physiological processes such as blood pressure regulation, cardiac metabolism, and myocardial repair. These rhythms also align cardiovascular reactivity with predictable environmental and behavioral cycles, facilitating normal function and influencing susceptibility to disease. Major adverse cardiovascular events—such as myocardial infarction, ventricular arrhythmias, and stroke—exhibit a distinct morning peak, underscoring the role of circadian regulation in cardiovascular health. Altering patterns of light exposure can disrupt circadian rhythms, leading to impaired reproductive function.
Natural light, particularly that received during the morning, helps synchronize the sleep-wake cycle, melatonin secretion, and other physiological rhythms. Conversely, exposure to intense light at night—especially light containing short wavelengths—can delay the circadian clock and disrupt sleep.
1) Melanopsin and photosensitive retinal ganglion cells — Nature (2002). A foundational piece of work for understanding how the eye detects light, with functions that extend beyond vision. https://www.nature.com/articles/415493a
2) The retina and human circadian regulation — New England Journal of Medicine (2007). A review of how light influences the biological clock, sleep, and human physiology. https://www.science.org/doi/10.1126/science.1067262------------------------------------------------------------------
Sleep, exercise in nature, and the consumption of raw fruits and vegetables—rich in a variety of colors, biophotons, enzymes, and phytochemicals—form a solid foundation for health. Circadian rhythms are endogenous biological cycles that regulate essential cardiovascular functions, such as blood pressure, heart rate, vascular tone, and metabolic homeostasis. The disruption of these rhythms—caused by factors such as shift work, exposure to artificial light at night, irregular sleep-wake cycles, or eating at inappropriate times—is increasingly recognized as an independent risk factor for cardiovascular disease. A growing body of research links circadian misalignment to key pathophysiological mechanisms, including endothelial dysfunction, oxidative stress, inflammation, and autonomic imbalance. Melatonin, a hormone produced primarily by the pineal gland, plays a fundamental role in circadian regulation and possesses potent antioxidant, anti-inflammatory, and cardiometabolic properties.
Maintaining a healthy circadian rhythm requires a consistent sleep schedule, regular exposure to light, and daily physical exercise. The use of artificial light in our homes and the prevalence of electronic devices have led more people to report shorter sleep duration and irregular sleep patterns. During sleep, our cells utilize this rest period to repair damaged structures and regenerate new cells following apoptosis.
The CLOCK (Circadian Locomotor Output Cycles Kaput) gene is a core component of the circadian clock and serves as a primary regulator of circadian rhythms, mediating various biological processes. Consequently, abnormal expression of CLOCK impairs its role within the circadian clock, as well as its broader function as a direct regulator of gene expression. Cortisol is a promising biomarker for detecting early signs of circadian rhythm disruption induced by stress. Early detection of a subpathological alteration in the circadian rhythm could point to a reversible state, offering an opportunity to preserve health.
It has been shown that circadian rhythm disruption is associated with an increased risk of developing obesity and obesity-related diseases, and is closely linked to tumorigenesis in cancer.
Emerging evidence suggests that exercise—a potent modulator of muscular adaptation—can also influence circadian regulation, providing a potential avenue for improving muscle repair in older populations.
Dysfunction of the 24-hour circadian rhythm is a common occurrence in older adults and tends to be more severe in individuals with age-related neurodegenerative diseases. The provided links are for those interested in further exploring the topic. https://www.tandfonline.com/doi/abs/10.1080/13813455.2021.1988110 (2024).--
https://www.mdpi.com/1422-0067/25/11/5846 (2024).--
https://www.nature.com/articles/s43018-024-00759-4 (2024).--
https://link.springer.com/chapter/10.1007/978-981-99-3746-2_25 (2024).--
https://www.nature.com/articles/s41420-024-01960-1 (2024).--
https://www.sciencedirect.com/science/article/abs/pii/S0167488924001253 (2024).--
https://www.mdpi.com/1467-3045/47/8/664 (2025).-
https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2025.1633835/full (2025).--
https://www.mdpi.com/1422-0067/26/18/9141 (2025).--
https://www.nature.com/articles/s41576-026-00962-2 (2026)
https://pmc.ncbi.nlm.nih.gov/articles/PMC12882775/ (2026)
https://www.sciencedirect.com/science/article/abs/pii/S0024320526000305 (2026)
https://pmc.ncbi.nlm.nih.gov/articles/PMC13139736/ (2026)
https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2026.1867223/full (20
Excellent article!
I have had floaters for as long as I can remember. Yes, I also had bad reactions to vaccines, grew up on a main road, in a major city, when leaded petrol was the go, ate some crappy food, had loads of wheat & dairy but didn't know I was Coeliac and allergic to dairy etc. No wonder I had floaters! Such a toxic load I carried...
I remember telling the Optometrist in my late teens/early 20s that I noticed more floaters when I was tired. He found that odd. But did not offer an explanation, other than floaters were proteins 'floating' about in the eye. In other words, he did not know why I should find them higher in number & more noticeable when I was tired. Nor did he tell me WHY I might have extra proteins floating about in my eye. Your article finally explained things to me. Thankyou!
But you know, Schneider might be onto something. If I shake my eyes about behind the eyelids (bright light not required, though!), the floaters DO move! They are most definitely mobile in the vitreous humour.
I'm in my late 40s now, and I have LESS floaters than 30 years ago! So much for being an age-related problem. As you rightly pointed out, it's a "correlation with duration of exposure
rather than with age itself." Perhaps I have far less floaters these days because I've been taking much better care of my health for many years, now.
However, I've noticed a few more floaters in recent times - since they've done heaps of chemtrails spraying around my area (Northern Rivers in NSW) INCLUDING FROM A C17 ARMY PLANE DROPPING THEM THE OTHER DAY, in tandem with the usual suspects (little white planes). Just in case you're wondering if the government is trying to poison and kill you, the answer is an unequivocal YES. Doesn't that make you feel better when you pay your taxes?
Anyway, we're now at the point where we keep the ball valve partially OPEN to let the water out before it makes it to the water tanks, and only close it when we want to save water that we know is clean, after all the sprayed chemicals have rained down! The water runs clear and stops smelling funky. You can also tell the difference in the air. I also get an itchy nose and cough again when they're spraying. Plus the air is often a bit frigid, even on warm days. When it's blue sky, it's easy to see if they're spraying. But I have to rely upon my bodily senses when it's all grey, however. Luckily, my body responds very well! So, at least we're avoiding capturing the poisoned water, which will be better for my vitreous humour - but unfortunately, we are all still breathing in those chemicals when THE GOVT does chemtrails.
Back to the eyes, I also think it's shocking that they basically put a blue light filter on the cataract lenses. I mean, sure, I have the blue light filter (night light) switched on on my laptop on all the time, but it's a laptop. My eyes don't want a hideously bright screen, nor do I want it to affect my ability to sleep at night if I'm using the computer late sometimes. But our bodies NEED sunlight! Our eyes need it! It affects so much! I've only ever owned one proper pair of sunglasses. Barely wore them. They always annoyed the bridge of my nose! I played tennis for years in the sun. No sunnies. I like seeing natural light, unfiltered, with my real eyes. I feel alive doing that!
We've been told for so long that the sun is BAD, and we should limit our exposure. Yet another way to get ill! I mean, sure, don't fry yourself in the middle of the day in high Summer, but I am just flabbergasted by how many LIES we have all been told about our health. From the very people we are meant to trust! And maybe that's the problem. We put our trust in others instead of holding onto our self-sovereignty. Instead of believing in ourselves and using our intuition, we willingly hand over our personal power to some nitwits masquerading as doctors with financial gain - at the expense of your health! - in mind. No wonder people are sick!
I have had cataract surgery on one eye. The 4 weeks of eye drops following that was horrific. I had terrible side effects. I haven’t had the other eye done and now finding out about the UV rays being blocked. I’m in no hurry. I spend a lot of time outside most especially early morning. I love to see the sunrise. I understand the circadian clock very well. I sleep very well most nights and sure don’t want to mess that up.
Don't miss the bit about castor oil applied to your eye lids (mention in this essay). Externally applied castor oil has healing benefits mentioned is other essays on unbekoming.
Shift work is associated with a significant increase in cancer risk. In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus houses the "master clock," which synchronizes with the ambient light cycle by directly coordinating efferent and neuroendocrine signals from the autonomic nervous system. Specifically, several proteins involved in the cellular clock mechanism are closely associated with positive and negative transcriptional feedback loops.
Various studies have revealed that shift workers face a higher risk of developing breast and prostate cancer, as evidenced by a strong correlation between long-term shift work (>20 years) and an increased cancer risk. Furthermore, previous research indicates that people in modern society have adopted less-than-healthy lifestyle habits—such as excessive caloric intake around midnight or continuous calorie consumption throughout the 24-hour day—which mimic aspects of shift work and may potentially increase the risk of prostate and breast cancer. The rest/activity rhythm has also been identified as a key factor, given its significant impact on the clinical management of patients with metastatic colorectal cancer (CRC), who often experience poor quality of life characterized by erratic rest/activity patterns.
The dysregulation of sleep-wake cycles, such as prolonged sleep deprivation, disrupts the immune system. Disruptions to normal sleep-wake cycles can lead to abnormal inflammatory responses—demonstrated by the upregulation of pro-inflammatory cytokines (notably IL-6 and CRP)—which serve as potential risk factors for various types of cancer, including ovarian, brain, breast, and colorectal cancer. In particular, hyperphagia and weight gain are closely linked to sleep deprivation; being overweight or obese facilitates increased secretion of adipokines and the release of macrophages from adipose tissue, which triggers chronic inflammation—leading to subsequent oxidative stress and DNA damage—thereby contributing to cancer development. Chronic disruption of sleep-wake cycles can cause greater DNA damage and impair DNA repair, representing a potential risk factor for tumorigenesis.
https://www.sleepfoundation.org/circadian-rhythm (2023).----
https://jhoonline.biomedcentral.com/articles/10.1186/s13045-022-01238-y (2022).---
https://link.springer.com/article/10.1007/s10549-022-06792-0 (2023).---
https://www.sciencedirect.com/science/article/pii/S1044579X23000366 (2023).---
https://undergradsciencejournals.okstate.edu/index.php/MRCMB/article/view/17654 (2023).--
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10069698/ (2023).---
https://www.mdpi.com/2072-6694/15/2/408 (2023)---
https://link.springer.com/article/10.1186/s12889-024-19518-2 (2024)---
https://www.nature.com/articles/s41523-025-00863-3 (2025)---
https://www.sciencedirect.com/science/article/pii/S2667005425000651 (2025)---
https://onlinelibrary.wiley.com/doi/abs/10.1111/jsr.70172 (2026)--
https://oem.bmj.com/content/early/2026/10/05/oemed-2026-111219.abstract (2026)--
https://pure.amsterdamumc.nl/en/publications/night-shift-work-circadian-disruption-and-risk-for-hormone-relate/ (2026)
Thank you for this illustrative explanation on an important health issue - circadian rhythm. Blessings to you!
I heard submarines are not as we are told. That they don't go as deep as we are told and that nuclear weapons do not exist
Really? How interesting and completely on point with the subject being presented here.