Growth, Nutritional Status, and Dietary Intake Patterns Associated With Prolonged Breastfeeding in Young Korean Children: A Nationwide Cross-Sectional Study

Abstract

Background Although the optimal duration of breastfeeding remains unclear, breastfeeding is generally recommended exclusively for the first 6 months of life, which continues into late infancy. However, the awareness regarding the effects of long-term breastfeeding is relatively low compared with that of breastfeeding in early infancy. We aimed to investigate the growth and nutritional characteristics of the children with prolonged breastfeeding (PBF) over 1 year. Methods This cross-sectional study was based on the data of children aged 12 to 23 months from the National Health and Nutrition Examination Survey (2010–2020) conducted by the Korean Center for Disease Control and Prevention. Data on anthropometric measurements, dietary behavior, and food and nutrient intake were extracted, and the association between PBF and growth, nutritional status, and dietary patterns were analyzed. Results Of the 872 children with a birth weight of ≥ 2.5 kg in the final analysis, 34.2% continued breastfeeding over 12 months of age, and their median breastfeeding duration was 14.2 months. Children with PBF were more likely to have lower current body weight ( P < 0.001) and weight gain ( P < 0.001), lower daily protein ( P = 0.012), calcium ( P < 0.001), and iron ( P < 0.001) intake per calorie compared with children weaned by 12 months of age or those who were never breastfed. Furthermore, they were started on complementary food at 6 months or later rather than 4–5 months ( P < 0.001), consumed cow’s milk earlier ( P = 0.012), and consumed probiotics as dietary supplements ( P < 0.001) significantly less commonly. When comparing the intake of food groups, children with PBF had a significantly higher intake of cereals and grains ( P = 0.023) and fruits ( P = 0.020) and a significantly lower intake of bean products ( P = 0.020) and milk and dairy products ( P = 0.003). Conclusion Korean children who continued breastfeeding over 12 months of age showed distinct characteristics in terms of growth, nutritional status, and dietary patterns in the second year of life compared to children who did not. Long-term additional research on their growth and nutritional status may be needed; however, these findings are significant as important fundamental data for nutritional counseling to establish healthy PBF.

Differences in Growth and Dietary and Nutrient Intake Patterns by Breastfeeding Status Over One Year Among Korean Children Aged 24–35 Months

“…Regarding food group intake, during 12–23 months of age, breastfed infants had higher intake of cereals and fruits and lower intake of legumes and dairy products. 15 Most of these differences remained in the same direction in this study, but only legume and soy product including soy milk and fruit intake were significantly associated with PBF status after adjustment. The lower intake of legumes and soy products in the breastfed group appeared to be largely due to the lower intake of soy milk.…”

“… 35 Regarding iron intake, a previous study has shown that Korean infants who are predominantly breastfed until late infancy are at risk of iron deficiency in the absence of adequate supplemental dietary intake. 18 Iron intake was also significantly lower in the PBF group at 12–23 months in the previous KNHANES study 15 ; however, it was higher in the PBF group at 24–35 months of age in the present study. This finding is probably related to the higher education level of mothers in the PBF group.…”

“…On the other hand, this study also suggests that iron intake above the recommended amount is due to higher overall food intake, not higher intake of a particular food, which is similar to the results of the 12–23-month-old toddler study. 15 Although the overall average intake and adequacy of intake have been improved compared with what was reported in KNHANES 2007–2009, 37 the rate of iron intake inadequacy in this age group still seems to be the highest among the pediatric age groups, except for adolescent girls. 19 38 39 Iron is particularly important for infant growth, neurodevelopment, and immune function 40 ; therefore, dietary intake should be emphasized.…”

“… 22 23 24 25 26 A recent Korean study of infants and toddlers from the NHSPIC found that infants who were exclusively breastfed for six months before the age of four were shorter and weighed lesser than those who were not, consistent with our findings. 23 However, the degree of significance of the growth difference during 24–35 months of age was less than that during 12–23 months of age using the same methodology, 15 with the difference in weight averaging 200 g vs. 400 g and the difference in weight gain decreasing from a 0.2 to 0.13. Additionally, the difference in height was not significant at age 2 years, nor was the difference in obesity.…”

“…A previous study using the last 10-year KNHANES data showed that Korean 12–23-month-olds not only had different growth outcomes based on PBF status but also had distinct differences in dietary patterns and nutrient intake. 15 In other words, children with PBF consumed more grains and fruits and, less soy products (including soy milk), dairy products, protein, calcium, and iron per calorie. In this study, a significant proportion of children aged 12–23 months were not fully weaned and were consuming breast milk or formula; hence, BF intake might have influenced the results of the study.…”