Table of Contents
What’s this
The circadian rhythm is an internal biological clock that allows us to live in balance with the external environment, adapting to different times of day and night. It is a system regulated by complex physiological mechanisms that works over 24 hours cycles of about three hours, which is why it is also called the circadian cycle.
Thanks to the circadian rhythm, the body is therefore able to change body temperature, blood pressure, heart rate, sleep-wake rhythm, hormone levels, metabolism and other parameters during the day.
How does it work
The processes of regulation of the circadian rhythm are mainly related to hours of light and dark which affect the expression of certain genes. In response to the expression of these genes, molecules involved in the circadian cycle are produced and secreted which affect various organs. In the hours of darkness, for example, la is produced and secreted melatonin, hormone capable of promoting sleep and rest. At dawn, the light leads to a gradual decrease in melatonin and at the same time there is an increase in cortisol, with consequent awakening of the organism.
During the morning, cortisol constantly increases improving physical performance and ability to concentrate. These are the hours in which we are most active and productive, in which we are able to carry out manual work that requires effort or to apply ourselves better in the study. After lunch, on the other hand, the performance decreases due to the digestive processes that require energy from the body, while from mid-afternoon, approximately between 15 and 18, the muscular, cardiac and pulmonary efficiency improve. late afternoon and until after dinner the body prepares for sleep, so the body’s activity slows down, including the digestive one: this is why light and easily digestible meals are recommended for dinner. There evening, around 9 pm, melatonin gradually rises again, to reach its peak during the night in order to guarantee optimal rest.
Circadian rhythm disturbances
When our biological clock is tuned to the external environment and responds optimally to light and dark, we enjoy a state of psycho-physical well-being. On the contrary, if the circadian rhythm is out of alignment with the external environment, we suffer from sleep disturbances that lead to fatigue, difficulty in maintaining attention and concentration, irritability.
Circadian rhythm disturbances can be caused by internal or external causes. Those caused by endogenous causes include delayed sleep phase syndrome, early sleep phase syndrome, and hypernothermal syndrome. In the first two cases, sleep occurs very late or earlier than conventional times: generally those who suffer from delayed sleep phase syndrome does not fall asleep before three in the morning; on the contrary, in the early sleep phase syndrome – typical in older people – the need to sleep occurs by 9pm. In both situations it can be difficult reconcile sleep with daily commitments and, especially in delayed sleep to-do syndrome, the tendency is to sacrifice several hours of sleep for work commitments. Pernictemeral syndrome, on the other hand, is very rare and can occur in people who are blind from birth and with consequent important alterations in the production and secretion of melatonin and cortisol.
Among the external causes at the base of circadian rhythm disturbances we find instead the jet lag syndrome linked to the time zone when traveling and the shift syndrome which occurs in some workers who work night shifts.
How to adjust it
If the circadian rhythm is out of alignment with the external environment, it is possible to intervene by regulating one’s own lifestyle. For example, it is not recommended to carry out demanding physical activities and sports from 18.00 onwards: it is better to engage in exercise and particularly heavy work in the morning or in the time slot between 15.00 and 18.00.
Relieving circadian rhythm disorders is also good take care of nutrition and, in this case, pay attention to the quantity and the amount of food introduced in the various phases of the day, opting for a rich and energetic breakfast in the morning, a normal lunch and a light dinner, low in fat and very elaborate foods, anticipating when possible the last meal of the day by 20.00.
To promote relaxation it can be useful to take care of the bedroom, applying all those strategies that can help you sleep well, so choose carefully mattress and bed linen, opt for soft colors, spread relaxing essences such as lavender and lemon balm, make sure there are no disturbing elements in the room.
Before going to bed, you can indulge in relaxing activities such as a hot bath or sip an herbal tea based on valerian, chamomile, passion flower. Better to avoid instead of staying at the computer or smartphone until a few minutes before sleeping.
An effective remedy for circadian rhythm disorders is the melatonin, available in the form of a dietary supplement to be taken before bed. Finally, to regulate the circadian rhythm it is recommended to always go to bed at the same time, so as to accustom the body to a routine aligned with the external environment.
Read also
