The invention relates to reamers used in downhole oil well operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs axisymmetric to an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provide a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.