The relationship between the behavior of the temperature-dependent heat capacity at constant pressure measured in different magnetic fields and the magnetocaloric effect in magnetic systems with and without discontinuous change of entropy is discussed. It is shown that the two are directly related to each other, and if the behavior of either property (i.e., the heat capacity or the magnetocaloric effect) is known, the general behavior of the second one can be predicted. The derived relationships are illustrated using several sets of experimental data and model examples.