Are you obese or overweight? Blame long term exposure to blaring horns and other noise from road traffic, said researchers.
The study, published in the journal Environment International, showed that a 10 decibel (dB) increase in mean noise level was associated with a 17 per cent increase in obesity.
There could be many reasons to explain this relationship. Noise generates stress, negatively affects our sleep, alters hormone levels and increases blood pressure.
Moreover, among other effects, sleep disturbance deregulates glucose metabolism and alters the appetite.
According to Maria Foraster, lead researcher from the Barcelona Institute for Global Health in Spain,
In the long term, these effects could give rise to chronic physiological alterations, which would explain the proven association between persistent exposure to traffic-related noise and cardiovascular disease or the more recently discovered associations with diabetes and obesity.
The study involved 3,796 adults and examined their body mass index (BMI), waist circumference, body fat, central obesity and overweight.
Foraster added, “Our findings suggest that reducing traffic-related noise could also be a way of combating the obesity epidemic”.
They also analysed exposure to noise generated by aircraft and railway traffic, but found no significant associations except in the case of long-term exposure to railway noise, which was associated with a higher risk of overweight, but not of obesity.