Activated Charcoal toothpaste or powders are user-friendly unless your teeth are super sensitive or your product has some strong chemicals in it which could hurt you. You can use them 4-5 times a week easily. It could be every day depending on the type of product you are using. Use them when you feel like your teeth need more protection than usual. This could be because you consumed more coffee, wine or oily food than usual which could leave a stain on your teeth or give you bad breath. You can also use this before going to an important date or a date with your crush!