Super-Chandrasekhar white dwarfs are a timely topic in the last years in the scientific community due to its connection to supernovae type Ia.Some early studies tackled the possibility of white dwarfs surpassing the Chandrasekhar limit by means of a magnetic field.More recently modified gravity has been highlighted as the reason for these stars to surpass the Chandrasekhar limit and becoming a supernova progenitor.However, in general simple assumptions are considered for the stellar structure and equation of state, which can lead to unreliable conclusions.In this work we intend to be rigorous and consider a realistic equation of state to describe the white dwarfs in general relativity and modified gravity, taking into account a nuclear instability, that limits the maximum mass.