Can you point to studies which confirm salt as the cause of these symptoms that MSG is unfairly blamed for?

I can eat consume copious amounts of salt without any ill effects, like finishing huge bowls of soup to the last drop.

I exercise a lot so I use salt liberally, and add it to water. If I don't supplement the salt intake, I start getting muscle cramps and a kind of lethargic feeling, particularly in hot weather.

I did an experiment, though, about 8 months ago: I started drinking bouillon. I prepared about a mug of hot water with a teaspoon of the soup stock. On one mug per day, I was okay. When I went up to three, the headaches and nausea showed up. I felt like crap, so I cut it short.

There is salt in that stuff, but that can't be it.