Flash photography has been a particular strength of Nikon SLRs for some time now, and the D3200 follows suit, with its implementation of Nikon's 3D Color Matrix II metering for flash exposures.
Being an entry-level model, the Nikon D3200 only offers two noise reduction settings: "On" (default) and "Off", so there's not a lot of flexibility in choosing how you want to make the trade-off ...