Look at the end of the day, you can't force feed him. It really is as simple as that. If he doesn't eat, then he doesn't eat.
Its probably just a stage that he is going through, my 3.5yr old is doing the same thing.
I just make sure i implement some of the foods into his diet, like if he wants yogurt, well thats his dairy intake, if he feels like eating strawberries all day, well thats his fruit intake.
Have you tried making up a platter for him? Im going to try this with my DS, put all the fruits and healthy options onto a platter and sit it in the lounge room so he can go to and from it.
With my thinking, my son is only 3.5yrs, he is stubborn and he does not want to budge, he has PLENTY of time to learn to eat things and how much and the consequences.
TBH i would be focusing on getting him to eat, whatever he likes (of course healthy options) let him eat it.
You just can't make him eat, its stressful for you and its stressful for him. And eventually he will rebel something chronic and when dinner time is coming up he already has it in his head he must refuse food because he knows its going to be stressful.
Maybe just relax a little, be calm, let him eat what he wants, whether thats strawberries for dinner or whatever, but it will be a lot less stressful for the both of you if you just relax.
Well thats my take on it. I went through the same thing with my oldest, i used to force him to eat his dinner really bad, eventually we both dreaded meal times and he would never eat. As soon as i relaxed, and let him lead it became a lot more easier and he was more prepared to try new things.
He is 7 now and its a FANTASTIC eater with a grea appeitite and loves trying new things.