Answer:
It poses a risk to his safety.
Explanation:
The information that he posted is personal information; his name can be used to identify him, the name of his school can be used to know where he is at what hours of the day, basically, he can easily be kidnapped at this rate. He can reduce the risk by taking off some information like the name of his school and his teachers's names. He can also reduce it by ceasing to post personal information about himself. I personally do not see how this affects his health though.
