Smoking and obesity, along with exposure to loud noise in the workplace, can lead to permanent hearing damage, the former by reducing blood flow to the ear, researchers say.

The BBC reported June 9 that researchers from Antwerp University led by Erik Fransen said that smokers and obese individuals ages 53-67 had reduced ability to pick out high-frequency sounds.

"The hearing loss is proportional to how much you smoke and your body mass index (BMI)," said Fransen. "It starts getting worse once you have smoked regularly for more than one year."

"There are so many young people who think that they can give up in middle age and escape some of the other diseases associated with smoking,"  said Amanda Sandford of the group Action on Smoking and Health. "In this case, some of the damage may already have been done."

The research was published in the Journal of the Association for Research into Otolaryngology.