An increase of 10 dB in the mean noise to which it is exposed means 17% more obesity. This concludes a new study, published in Environment International, which highlights how sustained exposure to noise is a public health problem and is more serious than previously thought.
Long-term exposure to noise from road traffic is associated with an increased risk of obesity. This is shown by the conclusions of a study in which the Institute of Global Health of Barcelona (ISGlobal) participated , a center promoted by the “la Caixa” Banking Foundation. The research has been published in the journal Environment International.
The work contrasts previous results that had already shown relationships between traffic noise and various obesity markers. For this, they had 3,796 adults who participated in the SAPALDIA Swiss cohort and to whom two follow-up visits were made between 2001 and 2011.
The research was based on objective measures such as weight, height, body mass index, waist circumference and the percentage of abdominal fat of each participant. These data were combined with estimates of the noise exposure generated by means of transport developed in the framework of the Swiss project SiRENE. (Also read: Strong evidence links depression to obesity)
“Our analysis shows that, effectively, people who are more exposed to road traffic noise have a higher risk of obesity. For example, we observed that an increase of 10 dB in the mean noise to which participants were exposed resulted in 17% more obesity, ” explains Maria Foraster, ISGlobal researcher and first author of the study.
The study also analyzed the noise exposure generated by air and rail traffic, without finding significant associations, except in the case of long-term exposure to noise from rail traffic, which was related to an increased risk of overweight, but not of obesity.
The methodological design contemplated the approach of the data from two different approaches: a transversal approach allowed to perform an analysis of the participating population at a specific time of the study and to examine several objective measures, while the longitudinal perspective evaluated the evolution of the obesity risk of the period investigated as a whole.
In both cases, the associations found with regard to traffic noise were consistent. This was not the case with regard to overweight, which was only related to exposure to traffic noise in the cross-sectional analysis. Nor was there a relationship between noise and change in body mass index, measured continuously, in longitudinal analyzes.
“Our study increases the evidence about the possible effects of traffic noise on obesity, finding the same results as previous studies in a new population. However, more longitudinal work is required to confirm the association and to examine some inconsistencies for which, to date, we have not been able to find a consensus explanation “, declares Maria Foraster.
Sustained exposure to noise is a public health problem that, unfortunately, is widespread and more serious than previously thought. Noise generates stress and affects sleep. Stress produces hormonal changes and increases blood pressure. In addition, the alteration of sleep dysregulates glucose and alters appetite, among other effects.
“In the long term, this can lead to chronic physiological alterations. This would explain why persistent exposure to traffic noise is associated with cardiovascular disease, which is proven, or recent associations with diabetes and obesity. Reducing traffic noise could also be a way to fight the obesity epidemic, “adds Maria Foraster.