Do I want or need a body voltage meter instead of a multimeter?

A multimeter seems to measure voltage difference between electrical ground and my body.

Ron Frazier told me I need a body voltage meter because a multimeter doesn't really measure body voltage.

Why ? What is the difference according to him?
I don't know who Ron Frazier is,
but this seems wrong because to my knowledge any descent quality multi-meter should do the job.
Cheap ones won't do it though.

https://slt.co/Products/BodyVoltageKits/HomeTestKit.aspx

It seems that a body voltage meter should be a true RMS meter.

https://www.fluke.com/en-us/learn/blog/electrical/what-is-true-rms says

"RMS = root mean square. Though its formula can be challenging to grasp, RMS essentially calculates the equivalent direct current (dc) value of an ac waveform. More technically, it determines the "effective," or dc heating value, of any ac wave shape.

An average-responding meter uses averaging mathematical formulas to accurately measure pure sinusoidal waves. It can measure non-sinusoidal waves, but with uncertain accuracy.

A more sophisticated true-RMS meter can accurately measure both pure waves and the more complex non-sinusoidal waves. Waveforms can be distorted by nonlinear loads such as variable speed drives or computers. An averaging meter attempting to measure distorted waves can be up to 40% low or 10% high in its calculations."

I think a human body hosts distorted waves.