Red Onion Apple Cider Vineger Shampoo It retains the pH level of your scalp and leaving you with soft, shiny and smooth hair. It tames rough hair cuticles and fights split ends. Apple cider vinegar & Onion extract have potent anti-bacterial properties and help fight infections of the scalp. They are naturally potent antioxidants, which is why they help reverse the effects of premature greying. It also make your hair uninhabitable for lice. It also can be used to fight dandruff owing to their rich anti-bacterial properties.