An ad from the early 1900's, with the opening paragraphs excerpted below:
Milly caught the bride's bouquet but everybody present knew that nothing would come of it...that she wouldn't be the next to marry by a long ways...and they knew the reason why, too.
People with halitosis (unpleasant breath) simply don't get by. It is the unforgivable social fault.
You never know when you have it—that's the insidious thing about it. Moreover, you are quite likely to have it, say dental authorities. Conditions present even in normal mouths constantly produce objections odors.
Don't take a chance
The one way to make sure that your breath does not offend others is to rinse the mouth with Listerine.
From How "Clean" Was Sold to America with Fake Science in Gizmodo. Worth a read if for nothing else than to see some of the photos of unbelievable ads about body odor. Even the use of the term “halitosis” to give bad breath a scientific term, as if it were some serious malady, is fiendishly clever. It's also shocking how the ads pictured are all targeted at women, reflecting the sexism of their times.
The tech industry has a lot to learn from consumer packaged goods companies about how to manufacture demand or consumer desire. The ads in this piece are negative and scare mongering, but companies like Procter & Gamble are just as good at generating desire with positive emotional triggers. It still feels like most tech brand advertising derives from viral stunts. One notable exception, of course, is Apple, most of whose ads now have more in common with fashion ads than technology ones.