Antioxidant capacity of human milk and its association with vitamins A and E and fatty acid composition

The antioxidant capacity of human milk reflects the presence and activity of multiple components, which prevent oxidative rancidity. The aim of this study was to use the Oxygen Radical Absorbance Capacity assay to assess human milk antioxidant capacity and find correlations with milk components.

Milk samples collected from 60 breastfeeding women at 1 month postpartum were assayed for antioxidant capacity, vitamins E and A, and fatty acids. Potential statistical relationships of concentrations of vitamins A and E and polyunsaturated fatty acids on the antioxidant capacity of human milk were determined.

Human milk antioxidant capacity was positively attributed to alpha-tocopherol concentration (rho < 0.05). The vitamin A concentration did not significantly contribute to milk antioxidant capacity, but was correlated to milk alpha-tocopherol concentration (r = 0.587; rho < 0.001). There was no evidence of an inverse relationship between polyunsaturated fatty acids concentration and the antioxidant capacity value of milk.

This study shows that alpha-tocopherol is an important contributor to the oxidative stability of human milk. Moreover, there was no evidence obtained to show that women who have high levels of milk polyunsaturated fatty acids are predisposed to lower milk antioxidant capacity.