DIY grounding and body voltage

I am looking into grounding to help with inflammation.  I made a grounding pad with a wire to a ground stake attached to an aluminum screen; but when I stand on the screen my body voltage increases.  Why would this be?  Also, when I stand on the wire without the aluminum screen my voltage goes negative, not to zero, why would that be and is that a bad thing?

Here are the results of the test that I did:

not touching ground is 2.6mV
w sock on wire = -30 mV then slowly reaching -50mV
bare foot = -50mV then reaching -25mV
with wool sock = is -2mV briefly then 1.5mV
bare foot on leather shiny jacket = 1.9mV
bare foot on leather more natural = 0mV then quickly levels to 1.8mV
barefoot on aluminum screen attached to wire = 470mV
barefoot on aluminum screen not attached to wire = 2.5mV
one foot off aluminum screen attached to wire = 430mV
one foot on aluminum screen attache to wire, one bare foot on wire = 160mV slowly rises to 350mV
a few minutes later on screen is 25mV, then back to 250mV a minute later vs. -25mV bare foot on wire

By wire do you mean you connected to the electric ground wire in the electric socket?
In some cases some ground wires in the electric socket will have some micro currents on and mV voltage.
In this case if you connect the ground pads to the electric socket you body voltage will rise.
I believe ground pads should be connected only to a ground pool in the yeard and only after testing it to see there are no  ground currents.
I hope this helps.
amirb

Thanks for your reply.  It is connected to a separate ground stake, not the ground outlet.  

How would I check for ground currents?

HI
Put an additional grounding pole 2 meters a way from the ground pole you already have and measure the voltage or current between them.
I hope this helps.
amirb

Thanks for sharing that trick.
I had a similar question some time ago here.
What voltage you consider to be too high ?

You are welcome.
I guess anything up then few mV.
Actually the current is more important.
If any current pass via the 2 poles, then there is a problem, even from few mA.
amirb