Alcohol

While having a few drinks may loosen your inhibitions the night of, drinking on the regular can cause a chemical reaction in the body that impairs the nervous system and greatly inhibits the manufacturing of testosterone, explains Pasquella. Plus, that cocktail may give you the nerve to talk to the most attractive man in the room—but when it comes to actual bedroom activity, booze will make you less sensitive and drowsy. Off the sauce, all sex can be as good as morning sex.