Methods for determining resistance to weight loss and susceptibility to binge eating episodes are described. The methods include determination of the presence of a obesity related alleles for a patient at single nucleotide polymorphism sites associated with the genes INSIG2, FTO, MC4R, and PCSK1. The total number of obesity alleles for the patient is indicative of the patient's resistance to weight loss and susceptibility to weight gain following bariatric surgery. The methods also include determining if a patient is homozygous for an obesity related allele at one or more single nucleotide polymorphism sites of the four genes.
