Introduction: Breast milk has several compounds obtained from food sources, such as conjugated linoleic acid (CLA). Objective: To compare the amount of trans fatty acids (TFA), CLA and docosahexaenoic acid (DHA) in the fat of breast milk with reported food consumption. Subjects and method: Descriptive study of 10 lactating Chilean women. Breast milk fatty acids were analyzed by gas liquid chrornatography and results compared to data obtained from a food frequency questionnaire. Results: Forty-two fatty acids were quantified, TFA (3.6%), CLA (0.8%), and DHA (0.2%). Of the 42 fatty acids, 4 CLA isomers and 3 TFA isomers were identified. The consumption offish, milk and meat was low. A positive correlation (p<0.05) between diet and the amount of two fatty acids, linolenic acid (LNA) and DHA, was found in breast milk fat. Conclusions: The amount of CLA and DHA found in food consumed and breast milk had a significant correlation; however, the amount of TFA is similar to that reported in other international studies.