Mexico ranks 2nd in adult obesity and 4th in milk intake worldwide. Low levels of IGF-1 have been related to obesity and can be reverted by milk intake. The rs6214 polymorphism has been associated with an increase in the expression of IGF-1. Therefore, the aim of the study was to evaluate the association between both, rs6214 polymorphism and milk intake, and obesity. We analysed 99 adult volunteers, with and without a history of milk intake, for the presence of this polymorphism through qPCR and body composition by electro-bioimpedance. Univariate logistic regression analyses showed that TT genotype is inversely associated with obesity and body fat mass. Besides, milk intake is also related to low obesity, body fat mass and visceral fat, and high percentage of lean mass. Multivariate logistic regression analyses confirm the univariate relationships, showing a clear inverted association between TT genotype, milk intake and obesity.