The circadian rhythm is our internal clock. It is synchronized mainly by the light and dark cycle, social interactions, nutrition and physical exercise. It regulates the production of various hormones throughout the 24-hour cycle.
The hormone melatonin has high values during the night, or in the absence of light, and low values during the day. It not only has the ability to regulate circadian rhythms, but also inflammatory pathways, as well as helping to eliminate free radicals.
In contrast, cortisol rises earlier in the day, when we should be more alert and feel less tired. But if our state of health is altered, or we take certain medications, such as glucocorticoids, or live under chronic stress, it can affect the levels of these hormones.
It is not surprising, therefore, that a relationship has been found between the alteration of these circadian rhythms with the activity of our immune system, resulting in inflammatory diseases such as rheumatoid arthritis.
Lack of sleep is related to lower resistance against infections and higher production of proinflammatory cytokines.
Sleeping less than 6 hours is associated with increased vulnerability to viral infection.
Recommendations to achieve a good balance of the circadian rhythm
- Regular schedules for sleeping and waking up. Do not use your cell phone alarm clock as an alarm clock, use a traditional one and avoid spending hours looking at social networks or email, subtracting hours of sleep. In addition, the use of screens can reduce melatonin levels due to exposure to blue light. There are even some alarm clocks that have sunrise simulation lamps, gradually increasing the light they emit and with nature sounds, so as not to wake us up too alert.
- Make your biological clock coincide with the environmental clock. It is better to go to sleep coinciding with the dark phase and expose ourselves to sunlight early.
- Keep the room ventilated during the day and at off-peak hours, and sleep at a temperature between 18 and 21 °C.
- Use programs that change the light emission spectrum of electronic devices by shifting the blue light towards yellow or amber, anticipating bedtime. Some examples are: Blue Light Filter, Blue Light Filter – Night Mode, Twilight, F.Lux, Screen Shader.
- Sleeping area is not the same as working area. Don’t take work to bed, your stress levels may stay elevated for longer. Good health is also synonymous with setting boundaries and self-care.
- Adjust meal times. During the day our organs prepare for digestion and the use of energy and nutrients, while at night the digestive process slows down and the body starts cell regeneration. For proper coordination, the biological clock sends signals to the various tissues and organs through the endocrine and nervous systems. Sleeping fewer hours can lead to higher food and/or energy intake throughout the day. If we do not eat at the right time, if we eat when we should be sleeping, those compounds that would aid in better digestion and absorption of nutrients, regulation of glucose and insulin levels, or energy use may be reduced. This may increase the risk of metabolic diseases such as diabetes.
- Melatonin and magnesium supplements. They may be useful in certain cases. They should always be prescribed by a health professional.
- Avoid substances that disrupt the circadian cycle. These are those that excite or cause drowsiness such as tea, alcohol or foods and drinks containing caffeine, especially 6 hours before bedtime.
- Perform regular and adapted exercise. If possible, avoid doing it close to sleeping hours.
- Reduce stress levels. Knowing the cause is important to know where to focus. What is the first thing you could change in your daily life to reduce it? Asking for help from our environment, going to a psychology professional, setting limits, working on flexibility instead of living under rigid decisions… are actions that can help us to better manage it. In addition, incorporating meditation into our lives can not only help us reduce stress and sleep better, but also improve the intensity of pain.
- Sleep the necessary time for each vital stage. According to the Spanish Sleep Society, the following hours are recommended.
- Newborns (0-3 months): 14-17 h.
- Infants (4-11 months): 12-15 h.
- Young children (1-2 years old): 11-14 hours.
- Preschool age (3-5 years): 10-13 h.
- School age (6-13 years old): 9-11 h.
- Adolescents: (14-17 years old): 8-10 h.
- Adults (18-64 years old): 7-9 h.
- Elderly (> 65 years): 7-8 h.
