Nothing is quite as gross as waking up with cigarette-soaked hair after a late night. (Thanks to the smoking ban, it’s at least not a frequent occurrence.) But ever wondered why you can’t shake that smoke smell out of your hair easily? It’s because your hair is like an absorbent paper towel, sopping up all the unique smells in the air while you go about your business, and fresh air isn’t enough to fix it. In fact, your strands also have a mild electrical charge that attracts charged pollutant particles in humid weather, making smells even more difficult to shake. The only remedy? You guessed it: A squeaky-clean shower with a good clarifying shampoo. In the poker game of shampoo and smoke, shampoo wins every time.

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