Dietitians of Canada

Feeding VLBW infants their mothers’ hindmilk is proposed as a means of increasing the energy density of fortified breast milk. Hindmilk is defined as milk produced after the first 3 minutes of milk flow, and has a higher fat and energy concentration than foremilk. Information is lacking on the fat-soluble vitamin content of hindmilk. The objectives of this study were: 1)measure concentrations of milk vitamin A, E, fat, energy, and nitrogen in foremilk vs. hindmilk fractions; 2)describe relationships between milk vitamin A and E concentrations and a)milk fat and energy concentrations, and b)maternal vitamin A and E intakes. Mothers (n=24) collected 24 h foremilk and hindmilk samples on day 24 (22-30) postpartum. A food frequency questionnaire was administered and demographics and milk pumping data was collected. Milks were analyzed by HPLC for vitamins (retinol, -carotene, -tocopherol and -tocopherol), gas chromatography for fatty acids, bomb calorimtery for energy and by Kjeldahl digestion and N analysis for total nitrogen. Milk volumes were significantly higher in hindmilk vs. formilk (82%) as were concentrations of retinol (50%), -tocopherol (80%), -tocopherol (70%), energy (30%), total fatty acids (70%), fatty acid groups (70-130%), and nitrogen (3%). Concentrations of milk retinol, -tocopherol, and -tocopherol were positively related (p<0.05) to milk fatty acids and energy concentrations. Finally, no significant correlation between maternal vitamin intakes (food & supplements) and respective vitamin content in foremilk, hindmilk or composite milk were found. This data is useful in assessing vitamin composition of human milk fortifiers and current recommendations for feeding VLBW infants.