What sounds like a lot of salt intake?
That sounds like a lot of extra salt intake. We make smoothies a lot or veggie ice creams (e.g., you can totally blend in cabbage without changing the taste and color of the ice cream). Also, we brainwash him with the concept that fruit and veggie are good. Those who don't eat them will get sick and will need shots from doctors. It's always been a struggle. But things do turn better - my son is 10 y.o. now and eats a little veggie and fruit everyday (not a lot, not his fav, but he eats now without much resistence). We've been working on this since he was 4.
Do you by any chance see an occupational therapist? My son has sensory integration disorder and many kids on the spectrum have overlapping sensory issues. My son also has issues with eating. His issues involve texture problems, gag reflex, chewing issues, hyper sense of smell, etc.
Our OT works on this.
There is a good book I believe called "food chaining" that goes through a process of getting kids to eat new foods and expand their diet.
We've had a lot of luck with 'dipping'. My son will try things and eat them that he otherwise wouldn't if he dips it into barbeque sauce or ranch dressing. Have you tried that. We also talk about being an adventurer like Indiana Jones and being daring. He doesn't have to eat what he doesn't like but he can try things. (and no pressure when he does-------- LOTS of praise if he eats it).