The academics of the Technological Institute of Higher Studies of the West (ITESO), Everardo Camacho and Claudia Vega Michel, have worked for several years on the issue of stress and its relationship with continuous exposure to noise.
Indeed noise annoys, but in addition, it is now known that indirectly it can also cause people to develop diseases due to viruses or bacteria, affect the quality of their sleep and consume more alcohol.
This knowledge has been possible thanks to the meeting of the exact sciences and psychology, and is enriched by the research carried out by these academics from the Department of Psychology, Education and Health of ITESO.
Among its conclusions is the certainty that there are differences between the stress levels of people who are chronically exposed to noise overdose - more than 85 decibels - and those who remain in quiet environments and, therefore, relaxed.
Five years ago, Everardo Camacho and Sergio Galán Cuevas, academics from the Autonomous University of San Luis Potosí, compiled a series of articles and published Stress and health: basic and applied research (Ed. Manual Moderno, 2012).
Within that book, Camacho and Claudia Vega published a systematic review on various investigations around the world that document the relationship between noise and stress.
“Also, we realized that there is a noise problem in the city. A severe problem caused by motor vehicles —which cause 80 percent of the shrillness—, airplanes and, of course, workshops and clubs ”, they report.
Hence the interest to enrich local research on stress levels related to noise and health.
In 2016, his research "Analysis of urban noisy areas, against non-noisy areas, with respect to cortisol levels, depression, hours of sleep and alcohol consumption" was published.
The specialists wondered if the daily inhabitants of three spaces in the city where the sounds are above 85 decibels, at least eight hours a day, for five years or more, have higher levels of stress.
As well as different behavior habits than those that make their lives in three areas that do not exceed 65 decibels, which is recommended by the World Health Organization (WHO).
The researchers conducted their study based on lifestyle reports and the analysis of the hormone cortisol, which is concentrated in saliva and rises in response to stressful stimuli.
Cortisol has an adaptive response that, in the face of stress, produces metabolic changes in the body: it turns off our immune system.
It is important to say that a prolonged blackout does not occur with sporadic situations that cause us stress such as a meeting, exam, or a sudden thunderous noise, but with chronic situations.
The research on noise as a stressor is formidable because, through the observation of saliva, it brings together the so-called hard or exact sciences with those of behavior. And because these analyzes, those of saliva and cortisol, are done in the ITESO laboratories.
In turn, the explanation of noise as a cause of stress, and of stress as a cause of physical conditions is fascinating, among many other reasons, because it talks about how the human body works.
To function, the immune system requires a lot of energy. At the same time, the positive sense of stress is the generation of an alert for survival, which also requires high doses of vigor, for example, fleeing from danger.
When we are subjected to chronic stress, wakefulness or immune blackout is chronic. This encourages a bacterium or virus to enter the body and attack it, the researchers note.
All, apart from the fact that noise waves have effects on the heart and circulatory system, and continuous exposure through hearing aids is causing young people to become almost deaf in their 40s, according to research from the National Autonomous University of Mexico (UNAM).
In the case of the ITESO research, Camacho and Vega took saliva samples from the participants four times a day. Then, through the test known as Elisa, they closely checked the spittlebugs, under a microscope, and followed a series of rigorous methodological steps.
Among them, they interviewed the owners of saliva about their daily behaviors. Then they discovered that those who are exposed to street noise on a daily basis - eight hours a day, for a minimum of five years - sleep an hour longer and consume more beer.
These data were not significant, so they remained an open line of research for the future.
What was demonstrated was the relationship between exposure to noise and the expenditure of cortisol in saliva. Those most exposed to loud sounds suffer the most stress and are therefore more vulnerable to physical illness.
After completing their work, Everardo Camacho and Claudia Vega affirm that it is important for people to identify whether they are continuously exposed to a noisy place. “There are people who think they get used to it and it is not true; what happens is that he loses his hearing and hears less noise ”.
After identifying the problem, they would have to take action, they say. For example, the use of earplugs and accessories that help reduce the impact of shrillness, and the performance of activities to deal with stress, such as physical exercise and recreational activities in quiet places, of course.
There are also telephone applications with which it is possible to calculate decibels to know what is the daily exposure to noise (goo.gl/0tjKOH) to request the intervention of the authorities, when necessary.
With their studies, these ITESO academics contribute to making the most invisible pollutant according to the WHO more evident: noise. Camacho affirms that the studies will continue. As with science, research generates certain knowledge, but asks new questions.