Still a serum test will only reveal the 2% of the potassium of the body. I said it would be constant, but a better expression would be within range.
Some of the most magnesium deficient (by symptoms) people I knew of, came up normal to high on the serum test. Some of the most hypo thyroid people I knew, came out hyper thyroid upon testing. There is, IMO a question if the tests are valuable enough. For me not; it is so much easier to go by symptoms. But thats me.
Sulfur is something to consider as it increases the permeability of the cell wall itself. Nutrients in, waste out, the sodium / potassium pump. It may be the missing link for some. //www.curezone.org/forums/fm.asp?i=2012733#i