Measuring how much current is required before a person perceives this sensation allows determination of their taste sensitivity.

The 28 smokers in the study group scored worse than the 34 non-smokers. Upon close examination with a contact endoscope, the smoker's tongues had flatter fungiform papillae, with a reduced blood supply.

'Nicotine may cause functional and morphological alterations of papillae, at least in young adults,' Pavlos said.

These findings were published in the open access journal BMC Ear, Nose and Throat Disorders.