1. A magnetic memory comprising: a magnetoresistive element comprising a fixed layer whose magnetization direction is fixed, a recording layer whose magnetization direction is variable and a nonmagnetic layer disposed between the fixed layer and the recording layer, wherein an MR ratio is expressed by MR ratio =(Rap-Rp)/Rp if a resistance value obtained when the magnetization directions of the fixed layer and recording layer are set to a parallel state is set to Rp and a resistance value obtained when the magnetization directions of the fixed layer and recording layer are set to an anti-parallel state is set to Rap, and a direction of a read current is set to a first direction in a case where an expression of MR ratio ≧|I c+ /I c− |−1 is satisfied if a critical current of the first direction used to write the magnetoresistive element to the parallel state is set to I c− and a critical current of a second direction used to write the magnetoresistive element to the anti-parallel state is set to I c+ .