Abstract <p>In this paper, a fresh viewpoint is given towards the anomeric effect (or Edward–Lemieux effect) regarding six membered rings and sugars from solely a conceptual density functional theory (CDFT) analysis. In this regard, we present our results and discussions with the corresponding quantum reactivity descriptors and principle of reactivities emerging from CDFT towards a series of selected compounds. The experimental axial orienting series is significantly recovered by this quantification, which also provides a new rationalisation and the first theoretical study of the effect in spiroketals. Indeed, [6,6] Spiroketals and derivatives where added to assess and rationalise the anomeric effect with CDFT in order to predict the most stable conformation as the synthesis of such systems is now progressing. At last, a general density based rationalisation is given for the anomeric effect and a combination of principles allows one to correctly retrieve the most stable conformer.</p> Graphical abstract <p></p>