Reference Values for Fat-Soluble Vitamins in Human Milk: The Mothers, Infants and Lactation Quality (MILQ) Study

This fourth article in the series presenting reference values for nutrients in human milk describes the values for the fat-soluble vitamins A, E, and D. The Mothers, Infants and Lactation Quality (MILQ) and Early-MILQ studies collected human milk samples at multiple times during the first 8.5 mo of lactation, from 1242 well-nourished women in Bangladesh, Brazil, Denmark, and The Gambia. Vitamins A and E were measured using high-performance liquid chromatography, whereas vitamin D was measured by liquid chromatography-tandem mass spectrometry. Milk fat-soluble vitamin concentrations from the MILQ study were compared with those used by the Institute of Medicine (IOM) for setting recommendations for nutrient requirements of infants and with other selected data sets. MILQ median concentration was on par with the value used by the IOM for retinol activity equivalents except in early lactation, when they were higher. For α-tocopherol, MILQ median concentration was 76% of the IOM value. The estimate of 0.89 mg/L γ-tocopherol is novel, given that the IOM does not define a concentration in human milk. Although it is known that human milk does not meet infant requirements for vitamin D, results of the MILQ study suggest that actual median concentrations are 60%-80% of those estimated by the IOM. Total daily median intakes from 1 to 6 mo were 97%, 75%, and 6% of IOM adequate intakes for vitamin A, α-tocopherol, and vitamin D, respectively. The MILQ fat-soluble vitamin estimated percentile curves are provided to enable comparison and interpretation of data from other studies.