Association of serum and erythrocyte zinc levels with breastfeeding and complementary feeding in preterm and term infants.

Zinc is an important nutrient involved in cell division, physical growth, and immune system function. Most studies evaluating the nutritional status related to zinc and prematurity were conducted with hospitalized preterm infants. These studies show controversial results regarding the prevalence of deficiency, clinical implications, and the effect of zinc supplementation on mortality, infectious diseases, and growth in these groups. This study aimed to compare serum and erythrocyte zinc levels in a group of preterm and full-term infants after 9 months of age, and related the zinc levels to dietary intake and anthropometric indicators in both groups. This cross-sectional study compared 43 preterm infants (24 to 33 weeks) aged 9-24 months to 47 full-term healthy infants. Outcome measures: anthropometric indicators and dietary intake. Blood sample for serum and erythrocyte zinc levels (ICP-MS, Inductively Coupled Plasma Mass Spectrometry). There was no difference between the groups regarding the mean of serum and erythrocyte zinc. Variables associated with higher serum zinc levels were breastfeeding at evaluation (ß = 20.11 µg/dL, 95% CI 9.62-30.60, p < 0.001) and the later introduction of solid foods (ß = 6.6 µg/dL, 95% CI 5.3-11.4, p < 0.001). Breastfeeding was also associated with higher erythrocyte zinc levels. The zinc levels were adequate in both groups, there was no association with anthropometric indicators or dietary intake and were slightly influenced by breastfeeding and time of solid food introduction.

Association between ultraprocessed food intake and C-reactive protein levels in preterm and term infants.

OBJECTIVES: This study aimed to examine associations between consumption of ultraprocessed food (UPF) and C-reactive protein (CRP) levels in a sample of term and preterm infants. METHODS: In this cross-sectional study, 43 preterm infants (<34 wk), chronological age between 9 and 24 mo, were compared with a group of 47 healthy term infants of the same age. Data were collected on dietary intake, anthropometric measures, and serum CRP level (mg/L). The main exposure of interest was the consumption of UPF (excluding all types of milk), measured as the percentage of total energy intake. RESULTS: The mean birth weight, gestational age, and corrected age were 1,245 ± 381.7 g, 29.9 ± 2.3 wk, and 14.3 ± 6.4 mo, respectively, in the preterm group. Infants in the preterm group consumed UPF less frequently (27-67.5% versus 40-87.0%; P = 0.038) but in a greater amount relative to total energy intake (39.8% [19.1-59.1%]) versus 29.0% (14.5- 41.9%; P = 0.040) when compared with the term group. There was no statistically significant difference between the preterm and term groups regarding CRP levels. The consumption of UPF (percentage of energy intake) was independently associated with CRP levels (ß = 0.007; 95% CI, 0.001-0.014; P = 0.034). A significant interaction between being born preterm and UPF consumption was found for CRP levels (P = 0.049). Breast-feeding was not associated with lower consumption of UPF in both groups (24-75.0% versus 43-79.6%; P = 0.404). CONCLUSIONS: There is a positive relationship between UPF and CRP levels among infants, irrespective of excess weight. At the clinical practice level, a better comprehension of the associations between food processing and chronic inflammation may aid in individual dietary guidance.