Do-loop question: Can an index ever be

This is a question I've wondered for a long time:

Can the beginning index for a Do-loop ever be <1 (e.g., 0)?

In recent practice, I discovered that using 0 as a starting value causes a crash, e.g., :

!     Initialize several variables for later use:
      do j = 0,N
        TwLev(j) = Tw_out + j*DeltaTwLev
        WaLev(j) = Wa_in
        HaLev(j) = Ha_in
      enddo

forrt1: severe (408) : fort: (3): Subscript #1 of the array TwLev has value 0 which is less than the lower bound of 1

The error message seems to indicate that 1 is the lowest acceptable integer.  Any thoughts on this?