Why Does a Multimeter Show Voltage Across My Body? Human Body as Battery & Electrolyte?

I'm a layman who's been wondering about batteries and electricity and have a few questions.  Forgive my lack of knowledge and thanks for any info you might have.
1. If I switch to DC voltage on a multimeter and hold the red probe in one hand and black probe in the other hand I get a reading of around 10 millivolts.  Why is this?  Is it because the human body is a kind of battery that generates electricity?
2. I hold an AA battery between my index finger (covering positive) and thumb (covering negative).  I slip a probe between that same index finger and the positive end of the battery.  I hold the black probe with my other hand. I get the full reading of the battery.  Why is that?  Is the current passing through my body?
3. Now this is the question that mosts interest me and is really what I'm trying to get at:If the human body is a battery, is the blood the electrolyte?  Would it then be possible to pass ions of different types through the blood?  Maybe this could be therapeutic for some conditions?
Again thanks for any info,Steve L.

Accounting Coursework Writing Services are hard to come across for those in need of Accounting Writing Services and accounting essay writing services. 

Hi.
1) The human body is an electric Wire (about 2000-50000 Ohm) and it is also an Antenna2) The body is similar to a potentiometer...3) Not.... to generate voltage you need two plates of opposite charge (example Zinc and Copper) and a fluid that transports iones.
RegardsGiovanni Di Maria

Fascinating!  Thanks for the info.  I wonder if there's an electrical apparatus that could  introduce copper ions into the bloodstream?  Or maybe drinking them?  It might help Covid. 

Steve,1) There can be many reasons for this, and it's probably a combination of all of them.  Here's another:  Every junction of two materials forms a small battery, so touching the probes makes two small batteries, and unless the materials in them are identical, there's a small difference between their voltages.  That includes all impurities on the probe surfaces.The body also does have many electrical things going on inside it.  That's also why things like EKGs and polygraphs (lie detectors) work, by small amounts of electricity generated by our bodies.2) Your body conducts electricity.  Each finger might have a potential that's close to that of the battery terminal it's touching.  There is a rather small current passing through your body too, but that causes the voltage to become smaller because of voltage drop between the battery and the probes.  Voltage doesn't require current; they are two different things but both related to "electricity".3) Who says the human body is a battery?  It's true that many things inside our bodies act like batteries, but I wouldn't claim that the body IS a battery.  Just about all fluids in our body (most of which is blood) act as an electrolyte because of their ionic content.  Ions of different types already flow through our blood.  I'm sure that is a component of how some medicines work.  Ions in liquids are not unusual.Please don't even think about treating COVID-19 with copper!  Ions or otherwise.  Don't do stupid things.  Don't listen to the orange dude.

By the way, I seriously doubt that an "electrical apparatus" could somehow introduce or transport copper atoms into our bodies.The ways to add matter to our bodies are by eating, breathing, or direct insertion via hypodermic needle.  Not much can move through the skin barrier, but a little does get in that way too.  Other ways are far more efficient.Electricity generally involves the movement of electrons, not entire atoms, whether or not they are ionized.  (Yes, fluids are somewhat different, because many have free ionized atoms too which are free to move, but they can't get through a barrier.)

Thanks for the info!  I'll be very careful before I drink any copper ions--or hydroxychoroquine or lysol for that matter. 

The battery effect you observe in 1) is probably occurring at the surface of the skin where the probes are touching.  A battery requires dissimilar metals, electrolyte between them and a conductive path between them.  (The same three are required for corrosion and for electroplating, all of which are the same phenomenon).I just tried the same with my meter and got a few mV as you did.  Then I licked one finger and saw little change.  But with both fingers licked I saw over 200 mV.Interestingly, Luigi Galvani discovered what he termed "animal energy" when he probed the legs of a freshly dissected frog with metal instruments and saw the legs jump.  What he didn't realize was, he had dissimilar metals, electrolyte (frog juices) and a conductive path through the probes when they touched.  The resulting electrical current also flowed through the still-alive nerves of the legs and stimulated the muscles, causing the legs to twitch.   A few years later (1800), Alessandro Volta came along and figured all that out and started building batteries by stacking up alternating layers of copper, salt-soaked blotter paper and zinc.  He had no "volt" meter to measure the "voltage" so he used the sensations of current flowing through his body to judge the potential his batteries developed.   Obviously, his discovery of so called steady or dynamic electricity (vs. static electricity) was so important that the unit of electric potential was named after him.  The galvanic protection that a zinc coating on steal provides against rusting was named after Galvani.Best,JD