Without acquisition circuitry, you won't read anything more significant than noise. This could be useful or not, depending on your application.
If you are trying to make a (very) rough touch detector, add some static discharge protection to an ADC port, identify peaks of variation and go for it.
But if you are trying to do somewhat serious signal processing and interpretation, you will definitely need amplifiers and filters.
As a rule of thumb, your total gain of the circuit should be enough so that the signal amplitude measured is slightly below the reference voltage of the ADC. Filters to be used include notch main filters and band-limiting anti-alias filters.
I would like to ask you to kindly expand on your explanation of the desired application.