Abstract: The invention concerns the use, as paper-making additive other than a standard mass additive or water treatment additive, of a starchy composition containing at least a cationic starch material. The invention is characterised in that said composition has: a fixed nitrogen proportion not more than 2%, preferably between 0.1 and 1.9%, said percentages being expressed in dry weight relative to the composition dry weight, and a viscosity, determined in accordance with a test A, of not more than 1600 mPa.s, preferably between 5 and 1500 mPa.s. Some of the starchy compositions, selected on the basis of their fixed nitrogen proportion and their viscosity, are also useful in numerous other fields of application, and in particular as mass additives in paper-making.