Cosmo Wants You To Get an STD!
Otherwise why would they they print advice like "Brush your teeth with minty toothpaste before going down on me. It'll feel extra shivery." - Patrick, 24.
Aside from not believing that "Patrick" gave that advice at all but it was generated during some sort of "How To Ruin Sex for Straight Women" type of brainstorming meeting, it's a great way to possibly cause bloody wounds in your mouth so you can be extra prone to infection when sucking cock.
I know that I am not a heterosexual woman and all and thus not their target audience, but bad sex advice pisses me off to no end. And our culture is lousy with it.