Comparisons of Breast Milk Fatty Acid Profiles in Overweight and Obese Women

Breast milk composition is affected by several factors such as maternal diet and body mass index. Milk fats include a major calorie content of the milk, which changes dramatically throughout the lactation. The aim of the present study was to assess breast milk fatty acid profile in overweight and obese mothers and its correlations with maternal body mass index.

Milk samples were collected from 73 healthy lactating women referring to various health centers in Mashhad. Data were collected using food frequency questionnaire to assess the maternal dietary intakes. Breast milk fatty acid profile was assessed using gas chromatography.

Breast milk content of saturated fatty acids was higher in obese mothers than overweight mothers (p = 0.03) with positive correlations with maternal body mass index (r = 0.256; p = 0.037). Furthermore, breast milk monounsaturated fatty acids were negatively correlated with pre-pregnancy body mass index (r = -0.385; p = 0.003) and pre-pregnancy body weight (r = -0.276; p = 0.026). However, no significant correlations were observed between the maternal body fat mass and fat proportion with the breast milk fatty acids (p > 0.05). Moreover, no significant associations were seen between dietary saturated fatty acids, milk monounsaturated fatty acids, polyunsaturated fatty acids, n-3 polyunsaturated fatty acids and n-6 polyunsaturated fatty acids with the corresponding fatty acids in breast milk (p > 0.05).

Based on the results, breast milk of the obese mothers included higher proportion of saturated fatty acids, while no significant differences were observed in the contents of milk monounsaturated fatty acids and polyunsaturated fatty acids between the overweight and obese women. Furthermore, maternal pre-pregnancy body mass index was negatively correlated with the contents of milk monounsaturated fatty acids, while it was positively correlated with saturated fatty acids contents.