baking powder contains alkaline and acidic substances, and the acidic substance is alum. If used too much, it will do harm to the body and bring a series of diseases. Now there are clear regulations that prohibit baking powder from adding substances harmful to health, that is, alum in traditional baking powder Now baking powder on the market will replace alum with other acidic substances, and it is aluminum-free baking powder, which will not cause harm to human body.