Of course industry scientists were well aware of this, but well aware that real smokers don’t smoke light cigarettes like machines. Partly by covering vent holes with fingers, and partly by inhaling more per cigarette, smokers inhaled more tar and nicotine from light cigarettes than was being measured by the machine testing method used to create the numbers printed on the packs. Companies like PM were also conducting surveys of smokers to find out their reasons for switching to Lights in high numbers. The results clearly showed that smokers believed so called “Light” and “Lowered Tar and Nicotine” cigarettes to be less harmful to health.

The companies knew that in fact the smokers don’t typically absorb less tar and nicotine from Light cigarettes and cenrtainly that the numbers printed on the packs did not reflect true absorption. However, the companies did nothing to inform consumers of this. They were happy to let consumers be tricked into continuing to smoke light cigarettes (rather than quit), in the false belief that these were less harmful.

It wasn’t until decades later (after losing their first product liability lawsuit) that some companies attached “onserts” onto the packs to explain this to consumers.