Nutrient Intake and Plasma and Erythrocyte Content Among Lactating Mothers of Hospitalized Very Preterm Infants: Associations with Human Milk Composition

Background/Objectives: Lactating mothers have increased nutritional requirements, but nutritional adequacy is difficult to achieve. Additionally, human milk (HM) composition depends on maternal diet. However, the nutritional intake and status of mothers with hospitalized very preterm infants (MHVPIs) (<32 weeks of gestational age) have rarely been assessed. Hence, the aim of the present study was to determine the intake of macronutrients, micronutrients, and lipids, as well as the nutritional status of MHVPIs. The results were compared with a group of HM donors (HMDs), and associations with HM composition were evaluated using multiple linear regression. Methods: For dietary assessment, a 5-day dietary record including supplement intake was completed by 15 MHVPIs and 110 HMDs. Vitamins and fatty acids (FA) were determined in plasma and erythrocytes; minerals and methylmalonic acid were determined in urine; and macronutrients, vitamins, minerals, and the lipid profile were determined in HM. Results: Considering dietary reference intakes, the dietary evaluation of MHVPIs revealed a high percentage of inadequate nutrient intake in relation to total energy, as well as for iodine and vitamins B8, B9, C, D, and E. A high protein intake was observed. The percentage of energy from carbohydrates was low, whereas the percentage of energy from fat was high. However, the diet of MHVPIs did not differ substantially from the diet of HMDs. Associations were observed between the study groups (MHVPI vs. HMD) and the HM concentration of protein, several micronutrients, and fatty acids independent from intake and status. Conclusions: Deficient nutrient intakes did not appear to be exclusively related to MHVPI but rather seemed to be widespread in both study groups. However, for preterm infants, an insufficient supply of nutrients is critical and should be addressed in order to improve preterm infant's outcomes. Furthermore, we provided additional insights into the exploration of HM by relating its composition to prematurity.