My 6 yo DS has just started - like yesterday, but he's done it a couple of times - to threaten not to eat/refuse to eat when things are going badly. Yesterday, even though he was very hungry after school he would not eat until his father got home at 6.15. I think he was trying to make him come quicker. (works away Monday to Friday)
Today he was very cross because I asked him not to do something just before lunch. He said he wasn't going to eat until he got his way (which he wasn't going to because the thing he wanted to do wasn't safe).
Don't get me wrong, I don't think DS is about to start starving himself but I worry that if we don't handle this carefully the germ of a seed of a problem is there...