By the Dorelan Scientific Committee
Sleep is a very important factor for human health: it contributes to the balance of the body , of emotional strength and helps the memory consolidation [1]. Date the importance of sleep , its disorders or alterations they require attention in every age group. Epidemiological studies have shown that the prevalence of insomnia and the inability to create or maintain a good quantity and quality of sleep during nighttime hours increases with age [2]. Reduced sleep quality decreases an individual's ability to manage stress, increasing anxiety and irritability, consequently reducing productivity at work or study.
The sleep hygiene strategies are defined as a series of behavioral and environmental recommendations designed to promote healthy sleep [3]. Thanks to sleep hygiene strategies, people learn healthy habits and behaviors to promote during the day and in the hours before falling asleep, thus improving various aspects of their sleep. The factors that need particular attention to improve your sleep are: exposure to light, temperature and timing of meals. There light it is the primary synchronizer of the sleep-wake cycle. The duration of exposure to light, its intensity and spectral composition, affects the structure, quantity and quality of sleep [4]. Melatonin it is an important hormone that regulates falling asleep and nocturnal sleep and is synthesized by the epiphysis when it is dark. For this reason it is important to limit exposure to light in the hours before going to bed, trying to limit as much as possible or eliminate the use of electronic devices such as smartphones, PCs and tablets, as it has been scientifically proven that light emitted by light screens delays falling asleep and promotes disturbed sleep [5].
Another factor that can influence sleep is sleep temperature . Both room and body temperatures significantly influence sleep, as thermoregulation is a determining factor both for falling asleep and maintaining a good rest phase [6]. Our body, in preparation for sleep, activates a process of dilation of the blood vessels in the skin, facilitating heat loss and consequently producing a decrease in internal body temperature. If this process does not occur correctly, for example due to a room temperature that is too high (typical in summer) or too low (typical in winter), the quantity and quality of sleep is negatively affected. Studies state that the ideal room temperature should be 18-20 degrees, with a microclimate under the covers between 28 and 32 degrees [7].
Furthermore, to promote a correct reduction in temperature during falling asleep, it is recommended eat dinner at least two hours before going to bed. Digestion is a process that tends to increase body temperature, altering the heat dissipation process, leading to disturbances in falling asleep.
To conclude, here is a list of behaviors that are important to adopt to improve falling asleep and your sleep:
- Try to remain exposed to natural light during the day , especially in the morning hours, keeping windows and shutters open if you remain indoors;
- Decrease exposure to light in the hours before falling asleep (room light, bright screens of smartphones, PCs or televisions);
- Maintain the dark room at night ;
- Keep the most bedtime and wake-up times are as constant as possible;
- Maintain a temperature between 18° and 20° in the room where you sleep;
- Wear nightwear and blankets that allow you to have a comfortable temperature;
- Do not consume alcohol or caffeine in the hours before falling asleep;
- Have dinner at least 2 hours before going to bed;
- Read, listen to "relaxing" music, draw and meditate they are activities capable of promoting falling asleep, if carried out in one room other than the bedroom.
Bibliography
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[2] M. Montazeri Lemrasky, A. Shamsalinia, M. Nasiri, and M. Hajiahmadi, “The Effect of Sleep Hygiene Education on the Quality of Sleep of Elderly Women,” Aging Med. Healthc. , vol. 10, no. 1, pp. 32–38, 2019, doi: 10.33879/amh.2019.1830.
[3] MHH Leah A. Irish, Christopher E. Kline, Heather E. Gunn, Daniel J. Buysse, “The role of sleep hygiene in promoting public health: a review of empirical evidence,” Sleep Med Rev. , pp. 22: 23-36, 2015, doi: doi:10.1016/j.smrv.2014.10.001.
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[5] L. Exelmans and J. Van den Bulck, “Bedtime mobile phone use and sleep in adults,” Soc. Sci. Med. , vol. 148, pp. 93–101, 2016, doi: 10.1016/j.socscimed.2015.11.037.
[6] N. Obradovich, R. Migliorini, SC Mednick, and JH Fowler, “Nighttime temperature and human sleep loss in a changing climate,” Sci. Adv. , vol. 3, no. 5, pp. 1–6, 2017, doi: 10.1126/sciadv.1601555.
[7] G. Zheng, K. Li, and Y. Wang, “The effects of high-temperature weather on human sleep quality and appetite,” Int. J. Environ. Res. Public Health , vol. 16, no. 2, pp. 1–13, 2019, doi: 10.3390/ijerph16020270.