im 32 and in good shape. for quite some time now ive suffered from brain fog, spaciness and confusion. the only thing ive found that will help to lift this is to run and break and sweat and get my heart rate up. had many neuro tests all normal. been to many doctors and all dismiss that this could be heart or circulation related because of my age and apperaring to be heathy. any ideas?

My best guess would be the reactive hypoglycemia. I know you eat primarily protein and carbs. Why not try to get the carbs as low glycemic as possible. Legumes (beans peas and lentils) are loaded with protein fiber and very low glycemic carbs. Perhaps a couple weeks where most of your carbs are coming from legumes might feel better.
It would probably be diagnostic as well. Those low glycemic carbs are filling and last a long time.

I doubt it's your heart.

Perhaps you feel better with exercise because exercise stimultes the release of glycogen which raises the blood glucose...just a guess, there.

Brain fog was one of my main symptoms with neurocardiogenic syncope, I guess it could've also been caused by my tachycardia. I am guessing you have had at least an ekg. How about a holter monitor or event monitor? How about a TTT (tilt table test), that's what they use to diagnose NCS.

I originally was sent to a neuro with symptoms of fatigue and brain fog, and just feel'g like I was losing my cog. abilities. He tested for about a year before he decided just for the heck of it to check my heart. He ordered the ekg and holter monitor and from there sent me to a cardio. The cardio ordered the TTT.

These are just some ideas.