Chronobiology corresponds to the study of the biological rhythms of the organism. Respecting our internal clock, whether it is nutrition or sleep, would be the key to preserving our well-being and especially our health. Explanations.

Like all living things, our body is subject to biological rhythms that affect our brains and the functioning of our hormones and cells. Respecting and taking into account these rhythms in our daily life and in our activities are essential to maintain our body in good health. There are three main types of rhythms: 

• The circadian rhythm: a cycle lasting 24 hours which has an influence on the majority of the body’s functions and in particular on the sleep-wake rhythm, the body temperature and the cyclical secretion of several hormones; 
• The ultradian rhythm: they concern the organs and functions whose rhythm is faster than the circadian rhythm such as the heart or respiratory rate for example;
• Infradian rhythms: that is to say rhythms that exceed 24 hours such as the menstrual cycle.

We owe the progress of research on the different mechanisms of our internal clocks to three American geneticists who were awarded a Nobel Prize in 2017: Jeffrey C. Hall, Michael Rosbash and Michael W. Young.

Depending on the different times of the day, the body does not claim the same physiological and biological needs. It is estimated that 20 to 40% of the molecules produced by the body depend on our internal clock. Hence the importance of respecting these natural rhythms under penalty of seeing his state of health deteriorate.

According to the National Institute of Health and Medical Research (Inserm), circadian rhythm disorders are associated with an increase in several risks: 

• Cancers ; 
• Drowsiness and sleep disturbances;
• Impaired cognitive functions; 
• Metabolic and cardiovascular disorders;
• Mood disorders ;
• Dépression
• Anxiety.

Depending on the individual, there is a drop in body temperature at the best time to go to bed. At 22 p.m., the body begins to secrete melatonin, the sleep hormone, and the pulse slows down to prepare the body for sleep. It is the secretion of cortisol, the wake-up hormone, which will then help us get out of bed in the early morning.

Factors such as age, illness, poor lifestyle, sensitivity to light or night work can cause circadian sleep rhythm disturbance. Medical support may be necessary to understand the origins of the disorder and find a classic rhythm.

Still according to Inserm, the rate of food intake has an impact on health. Hence the importance of listening to your needs and respecting as much as possible a routine, which may vary from one individual to another, for taking meals. For example, studies have highlighted the fact that eating less than an hour before bedtime could have long-term repercussions on our health.

The principle of chrononutrition developed by Doctor Alain Delabos at the end of the 80s is based on this precept. It is based on the idea that food will not be assimilated by the body in the same way depending on the time at which it is eaten. It is therefore a question of consuming food groups at the appropriate times. “Many so-called chronoregimes or diets based on chrononutrition are already proposed, but their effectiveness and their superiority compared to other approaches have not been demonstrated by scientific studies”, however, recalls Inserm.