Why do elders rotate crystal salt, lemon around head?

Salt can be considered as the first antibiotic. Not only that, the salty and acidic substances would less affect the magnetic field. Keeping these properties if lemon and salt in mind, we revolve salt and lemon around the person.The salt and lemon when revolved around, it would kill all the bacteria around the person. It forms an aura layer of antibiotics around the person. Not only has this, revolving around the person balance the magnetic field too. This would make the person affected with drastic feel better.