New research suggests that menthol combined with nicotine in cigarettes inhibits the body’s ability to signal irritation from smoking.
Researchers at Georgetown University discovered that the menthol used in cigarettes acts as a painkiller on the nerves that transmit the effects of cigarette smoke to the brain.
"In addition to desensitizing the receptors in the lung and airways, menthol appears to slow or prevent the recovery of sensitivity after the first insult," the researchers say.
"The issue may be that menthol in the presence of nicotine may reduce the irritation enough that a smoker can inhale more deeply, bringing not just nicotine but toxic smoke products farther into the lungs," Ahern said in a press release. "While beyond the scope of this study, it is possible that such deeper inhalation of menthol cigarettes, to the extent it occurs, increases the already substantial health harms from smoking."
Read more; http://www.healthline.com/health-news/menthol-in-cigarettes-numbs-the-lungs-study-says-051615#3