Circadian rhythm influences body temperature, hormone release, blood pressure, mood, and much more. Its disturbance could lead to many diseases like type 2 diabetes, heart-related conditions, mental illnesses, and many others. What can you do to optimize your circadian rhythm?
What is circadian rhythm?
Circadian rhythm is the 24-hour internal clock that regulates the physical, mental, and behavioral changes that occur throughout your day in response to light changes in the environment around you (1). An example of light-related circadian rhythm changes is the sleep-wake cycle, where people usually sleep during the night and are awake during the day.
You need circadian hygiene
Circadian hygiene is not to be confused with cleanliness. It is about maintaining healthy habits related to nutrition, physical activity, socializing, and other factors (2). For example, maintain consistent and appropriate eating time, interval, and quantity, among others.
Does the circadian rhythm only control sleep?
No, circadian rhythm controls much more. Sleep is just a part of what is regulated by circadian control. It influences aspects of your body like (1, 3):
- body temperature
- hormone release
- food digestion and eating habits
- blood pressure
- mood
You can learn much more about how circadian rhythm influences your daily life by talking to one of our experts at an online complimentary consultation.
What regulates your circadian rhythm?
The circadian rhythm is controlled by a process called the central circadian clock. It is located in your brain’s suprachiasmatic nucleus SCN (4). SCN exerts its effects based on your exposure to light. When light hits your eyes, it is translated to an electrical signal, which converts to a chemical signal when reaching the SCN (5).
In addition to the central clock, there are other regulators (called peripheral circadian clocks) found in various tissues, organs, and systems of your body, like the liver, gastrointestinal tract, skeletal muscle, pancreas, and reproductive system, among others (4, 5). SCN works in conjunction with these peripheral clocks to regulate your circadian rhythm.
At Healthy Longevity Clinic, we have various diagnostic and therapeutic approaches to evaluate your circadian rhythm, diagnose problems related to it, and provide interventions if needed – not only to correct it if deviated but also to boost it. Visit our clinical programs page to find out more.
Circadian affects your major organs
The circadian clock is involved in regulating many of your bodily activities. Let us explore how that works in some organs and systems.
Gastrointestinal tract
The gastrointestinal tract is subject to circadian rhythm, where the circadian clock controls processes related to intestinal motility, gastric acid secretion, digestive enzyme release, and much more (4, 5). In other words, many of the functions of the digestive tract are regulated by the circadian clock.
Cardiovascular system
Research on the connection between circadian rhythmicity and the circulatory system shows that the circadian clock regulates many important functions, like blood pressure and heart rate (4, 6). In this regard, the circadian clock governs these components depending on the time of the day. For example, during sleep, your blood pressure decreases.
Skeletal muscles
Just like other organs and systems, skeletal muscles are also influenced by circadian rhythms. Studies have shown that the circadian clock controls the metabolic rate and muscle capacity during various times of the day and activities (4, 7). This is seen through multiple adaptations that occur to the muscle depending on whether your exercise is aerobic or anaerobic.
Regarding the connection between skeletal muscle and metabolism, researchers were able to link how changes in the circadian clock influence your skeletal muscles and their capacity to take up glucose (as a source of energy) (7). This means that skeletal muscles also play a role in regulating your blood sugar level.
Skin
Your skin is the largest organ in your body (4). It is affected by multiple factors, like light, hormones, temperature, and other factors. Believe it or not, even your skin is regulated by circadian clocks. In this context, researchers found that the circadian clocks regulate many functions, like water loss, skin growth, repair, blood flow, and even temperature (8).
It does not stop there. In addition to the various organs and systems, the circadian rhythm influences how your body processes and how treatments and medications produce their effects (9).
At Healthy Longevity Clinic, we have personalized diagnostic and therapeutic approaches that help realign or even improve your circadian rhythm. This way, your organs are in a better position to function optimally. Learn more about how to become a longevity hacker.
Disturbance of circadian rhythm can affect your health
Since circadian regulation is involved in many organs, its disturbance has been linked to several diseases.
Type 2 diabetes
The circadian rhythm is involved in regulating glucose metabolism by influencing several aspects that contribute to blood sugar uptake, regulation, and sensitivity, such as insulin, melatonin, physical activity, and much more (5, 10). Therefore, disrupting the circadian rhythm could potentially contribute to an increased risk of developing type 2 diabetes. In addition, when combined with adverse lifestyle, environmental, and behavioral aspects, the risk of type 2 diabetes substantially increases (10).
Cardiovascular diseases
Remember how we mentioned that the circadian rhythm controls many aspects of the circulatory system, such as the heart rate, blood pressure, blood coagulability, and others? This means that interrupting the natural flow of the circadian rhythm could potentially put you at risk of diseases affecting the heart and other organs (4, 6, 11).
For example, scientists found that misaligning the circadian clock by disrupting the sleep cycle resulted in a higher risk of developing heart diseases and fat accumulation in major arteries supplying the heart (12, 13). In addition, a misaligned circadian clock affects hormonal release, which is another factor contributing to the development of heart-related diseases.
It does not stop there. Studies have shown that the circadian clock even influences how the body of patients with heart disease responds to treatment and how their risk of complications changes throughout the day (11).
Gastrointestinal diseases
Since the circadian rhythm influences the activity of various parts of the digestive system, disruption of the 24-hour cycle could contribute to the development of diseases (14). For example, researchers found that the risk of gastroesophageal reflux disease (flow of acid from the stomach to the esophagus and mouth) is greater in people who work night shifts.
Studies attributed the above-mentioned effect to disturbances in circadian rhythm factors, like melatonin. In this regard, the scientific literature suggests that melatonin (mainly secreted at night) decreases stomach acid secretion and has anti-inflammatory properties.
In addition, there are other factors that contribute to preventing the reflux of stomach acid (14). Disruption of the circadian rhythm causes a disturbance in melatonin, which translates into an increased risk of stomach acid reflux.
Examples of other diseases that affect the digestive tract due to abnormalities in the circadian rhythm include inflammatory bowel diseases (both Crohn's disease and ulcerative colitis), stomach ulcers, and several types of cancers that affect the digestive tract (14).
Other diseases caused by circadian rhythm disturbance
The circadian rhythm plays a role in almost the whole body; therefore, its disturbance is linked to a large number of diseases. Examples of other diseases caused by circadian disruption include:
- cancer
- mental illnesses
- disorders that affect the neurons
- respiratory ailments
- immunity-related conditions
- and others (3, 15, 16).
How can you maintain and improve your circadian hygiene?
There are certain lifestyle modifications that you can easily implement to ensure that you maintain your circadian hygiene. Examples of these include (2):
- Avoid meals at least two hours before bedtime.
- Maintain physical activity and exercise regularly.
- Go to bed and wake up at regular intervals, preferably close to sunrise and sunset.
- Avoid prolonged exposure to electronics, especially close to bedtime.
- Maintain healthy eating habits with regard to food type, quantity, content, and meal interval.
- Make sure your room has a suitable temperature and is quiet.
At Healthy Longevity Clinic, we will assess your circadian health using various diagnostic measures and provide several options, treatments, and programs that could help you correct the problem and optimize its function. Start with a complimentary consultation with a specialist.
What is circadian rhythm?
Circadian rhythm is the 24-hour internal clock that regulates the physical, mental, and behavioral changes that occur throughout your day in response to light changes in the environment around you (1). An example of light-related circadian rhythm changes is the sleep-wake cycle, where people usually sleep during the night and are awake during the day.
You need circadian hygiene
Circadian hygiene is not to be confused with cleanliness. It is about maintaining healthy habits related to nutrition, physical activity, socializing, and other factors (2). For example, maintain consistent and appropriate eating time, interval, and quantity, among others.
Does the circadian rhythm only control sleep?
No, circadian rhythm controls much more. Sleep is just a part of what is regulated by circadian control. It influences aspects of your body like (1, 3):
- body temperature
- hormone release
- food digestion and eating habits
- blood pressure
- mood
You can learn much more about how circadian rhythm influences your daily life by talking to one of our experts at an online complimentary consultation.
What regulates your circadian rhythm?
The circadian rhythm is controlled by a process called the central circadian clock. It is located in your brain’s suprachiasmatic nucleus SCN (4). SCN exerts its effects based on your exposure to light. When light hits your eyes, it is translated to an electrical signal, which converts to a chemical signal when reaching the SCN (5).
In addition to the central clock, there are other regulators (called peripheral circadian clocks) found in various tissues, organs, and systems of your body, like the liver, gastrointestinal tract, skeletal muscle, pancreas, and reproductive system, among others (4, 5). SCN works in conjunction with these peripheral clocks to regulate your circadian rhythm.
At Healthy Longevity Clinic, we have various diagnostic and therapeutic approaches to evaluate your circadian rhythm, diagnose problems related to it, and provide interventions if needed – not only to correct it if deviated but also to boost it. Visit our clinical programs page to find out more.
Circadian affects your major organs
The circadian clock is involved in regulating many of your bodily activities. Let us explore how that works in some organs and systems.
Gastrointestinal tract
The gastrointestinal tract is subject to circadian rhythm, where the circadian clock controls processes related to intestinal motility, gastric acid secretion, digestive enzyme release, and much more (4, 5). In other words, many of the functions of the digestive tract are regulated by the circadian clock.
Cardiovascular system
Research on the connection between circadian rhythmicity and the circulatory system shows that the circadian clock regulates many important functions, like blood pressure and heart rate (4, 6). In this regard, the circadian clock governs these components depending on the time of the day. For example, during sleep, your blood pressure decreases.
Skeletal muscles
Just like other organs and systems, skeletal muscles are also influenced by circadian rhythms. Studies have shown that the circadian clock controls the metabolic rate and muscle capacity during various times of the day and activities (4, 7). This is seen through multiple adaptations that occur to the muscle depending on whether your exercise is aerobic or anaerobic.
Regarding the connection between skeletal muscle and metabolism, researchers were able to link how changes in the circadian clock influence your skeletal muscles and their capacity to take up glucose (as a source of energy) (7). This means that skeletal muscles also play a role in regulating your blood sugar level.
Skin
Your skin is the largest organ in your body (4). It is affected by multiple factors, like light, hormones, temperature, and other factors. Believe it or not, even your skin is regulated by circadian clocks. In this context, researchers found that the circadian clocks regulate many functions, like water loss, skin growth, repair, blood flow, and even temperature (8).
It does not stop there. In addition to the various organs and systems, the circadian rhythm influences how your body processes and how treatments and medications produce their effects (9).
At Healthy Longevity Clinic, we have personalized diagnostic and therapeutic approaches that help realign or even improve your circadian rhythm. This way, your organs are in a better position to function optimally. Learn more about how to become a longevity hacker.
Disturbance of circadian rhythm can affect your health
Since circadian regulation is involved in many organs, its disturbance has been linked to several diseases.
Type 2 diabetes
The circadian rhythm is involved in regulating glucose metabolism by influencing several aspects that contribute to blood sugar uptake, regulation, and sensitivity, such as insulin, melatonin, physical activity, and much more (5, 10). Therefore, disrupting the circadian rhythm could potentially contribute to an increased risk of developing type 2 diabetes. In addition, when combined with adverse lifestyle, environmental, and behavioral aspects, the risk of type 2 diabetes substantially increases (10).
Cardiovascular diseases
Remember how we mentioned that the circadian rhythm controls many aspects of the circulatory system, such as the heart rate, blood pressure, blood coagulability, and others? This means that interrupting the natural flow of the circadian rhythm could potentially put you at risk of diseases affecting the heart and other organs (4, 6, 11).
For example, scientists found that misaligning the circadian clock by disrupting the sleep cycle resulted in a higher risk of developing heart diseases and fat accumulation in major arteries supplying the heart (12, 13). In addition, a misaligned circadian clock affects hormonal release, which is another factor contributing to the development of heart-related diseases.
It does not stop there. Studies have shown that the circadian clock even influences how the body of patients with heart disease responds to treatment and how their risk of complications changes throughout the day (11).
Gastrointestinal diseases
Since the circadian rhythm influences the activity of various parts of the digestive system, disruption of the 24-hour cycle could contribute to the development of diseases (14). For example, researchers found that the risk of gastroesophageal reflux disease (flow of acid from the stomach to the esophagus and mouth) is greater in people who work night shifts.
Studies attributed the above-mentioned effect to disturbances in circadian rhythm factors, like melatonin. In this regard, the scientific literature suggests that melatonin (mainly secreted at night) decreases stomach acid secretion and has anti-inflammatory properties.
In addition, there are other factors that contribute to preventing the reflux of stomach acid (14). Disruption of the circadian rhythm causes a disturbance in melatonin, which translates into an increased risk of stomach acid reflux.
Examples of other diseases that affect the digestive tract due to abnormalities in the circadian rhythm include inflammatory bowel diseases (both Crohn's disease and ulcerative colitis), stomach ulcers, and several types of cancers that affect the digestive tract (14).
Other diseases caused by circadian rhythm disturbance
The circadian rhythm plays a role in almost the whole body; therefore, its disturbance is linked to a large number of diseases. Examples of other diseases caused by circadian disruption include:
- cancer
- mental illnesses
- disorders that affect the neurons
- respiratory ailments
- immunity-related conditions
- and others (3, 15, 16).
How can you maintain and improve your circadian hygiene?
There are certain lifestyle modifications that you can easily implement to ensure that you maintain your circadian hygiene. Examples of these include (2):
- Avoid meals at least two hours before bedtime.
- Maintain physical activity and exercise regularly.
- Go to bed and wake up at regular intervals, preferably close to sunrise and sunset.
- Avoid prolonged exposure to electronics, especially close to bedtime.
- Maintain healthy eating habits with regard to food type, quantity, content, and meal interval.
- Make sure your room has a suitable temperature and is quiet.
At Healthy Longevity Clinic, we will assess your circadian health using various diagnostic measures and provide several options, treatments, and programs that could help you correct the problem and optimize its function. Start with a complimentary consultation with a specialist.
1. Reddy S, Reddy V, Sharma S. Physiology, circadian rhythm. StatPearls [Internet]: StatPearls Publishing; 2022.
2. Moreno CRC, Raad R, Gusmão WDP, Luz CS, Silva VM, Prestes RM, et al. Are We Ready to Implement Circadian Hygiene Interventions and Programs? Int J Environ Res Public Health. 2022;19(24).
3. Farhud D, Aryan Z. Circadian Rhythm, Lifestyle and Health: A Narrative Review. Iranian journal of public health. 2018;47(8):1068-76.
4. Zhang S, Dai M, Wang X, Jiang SH, Hu LP, Zhang XL, et al. Signalling entrains the peripheral circadian clock. Cell Signal. 2020;69:109433.
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10. Mason IC, Qian J, Adler GK, Scheer F. Impact of circadian disruption on glucose metabolism: implications for type 2 diabetes. Diabetologia. 2020;63(3):462-72.
11. Rabinovich-Nikitin I, Lieberman B, Martino TA, Kirshenbaum LA. Circadian-Regulated Cell Death in Cardiovascular Diseases. Circulation. 2019;139(7):965-80.
12. Chellappa SL, Vujovic N, Williams JS, Scheer F. Impact of Circadian Disruption on Cardiovascular Function and Disease. Trends Endocrinol Metab. 2019;30(10):767-79.
13. Medic G, Wille M, Hemels ME. Short- and long-term health consequences of sleep disruption. Nature and science of sleep. 2017;9:151-61.
14. Voigt RM, Forsyth CB, Keshavarzian A. Circadian rhythms: a regulator of gastrointestinal health and dysfunction. Expert Rev Gastroenterol Hepatol. 2019;13(5):411-24.
15. Fishbein AB, Knutson KL, Zee PC. Circadian disruption and human health. J Clin Invest. 2021;131(19).
16. Walker WH, Walton JC, DeVries AC, Nelson RJ. Circadian rhythm disruption and mental health. Translational Psychiatry. 2020;10(1):28.
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