5 year old with eating issues after allergies

[Pinkponk1]

Hi all I couldn't find a thread related.
My 5 yo son isn't gaining weight/height like he was and the doc has checked, had blood tests etc and all normal. He seems to have no appetite at all and I feel like I resort to coaxing him to eat which I worry now has lead to him using food as a control thing. Every meal time is a battle plus I'm lacing his food with butter cream cheese etc which can't be healthy!! He had allergies which has has outgrown so I've always had to be careful about what he eats which I'm sure can create hang ups. One other thing is he throat clears a lot and I always assume he has a sore throat but docs have checked countless times and said tonsils not too much of a prob.
Any advice anyone?? Thanks mums xx
Ps I'm only guessing this is the reason for his tiny appetitie any other thoughts?

Maybe he doesn't like the food with the added butter and cream, what happens if you just put normal healthy food on a plate and ignore his eating, just chat about something unrelated?

He loves butter it's an odd one!

has he been tested for environmental allergies?

and dont worry about stuffing with butter or double cream, anything you get thats high calorie and isnt a food allergy is ok.

We were advised to do the same for our son when he was small. he eats a healthy diet, one that is free of his allergies.

small amounts of high calories food, 3 meals and small snacks are best way forward.