Eating plenty of fluoride toothpaste is likely to only lead to stomach upset. But eating a lot of fluoride toothpastes can be fatal. Children are more vulnerable to fluoride poisoning. Just one toothpaste tube contains enough fluoride to kill a child weighing 30 kilograms. If a child consumes only 3% of a toothpaste, he will inject an acute fluoride intoxication, which is similar to flu, dizziness and pain.