What effects may children's toothpaste containing fluoride have on the human body?

Children under 6 years old have imperfect swallowing function and are not skilled enough in brushing their teeth. There is often a lot of toothpaste remaining between the teeth, and they may even swallow mouthwash. If they use fluoride toothpaste for a long time, they will This leads to increased fluoride intake in the body, resulting in "dental fluorosis" (commonly known as "macular plaque"). Popular science: Any substance may cause poisoning due to excessive intake, and fluoride toothpaste is no exception. However, fluoride toothpaste is safe if used normally. For an adult weighing 60 kg, the recommended daily fluoride intake should be less than 4.2 mg. The fluoride concentration of adult toothpaste is generally 1000~1500 mg/kg. If you use 1 gram of fluoride toothpaste (about 1 cm long paste) and brush your teeth twice a day, the total fluoride content will be only 2~3 mg. After brushing your teeth, spit out the toothpaste slurry and most of the fluoride has been spit out. The remaining fluoride swallowed into the body is only a small part and will not cause harm to the human body. For children, especially those under 6 years old, due to poor swallowing reflexes, they are prone to swallowing toothpaste when brushing their teeth. Care should be taken to prevent excessive fluoride intake. On the one hand, children should use children's toothpaste with less fluoride (fluoride concentration is generally 250~500 mg/kg), and should not exceed 2 times a day, and the amount used each time should not exceed the size of a pea. On the other hand, parents should supervise their children's toothbrushing and encourage them to spit out the toothpaste and not swallow it. Don’t worry too much about occasional swallowing, because even if you use toothpaste containing 1500 mg/kg of fluoride, a 1-year-old child would have to take 33 grams at one time to reach a potentially toxic amount. The Centers for Disease Control and Prevention also recommends that children start using fluoride toothpaste after they are 2 years old.