Xiang Study: an association of breastmilk composition with maternal body mass index and infant growth during the first 3 month of life

Abstract

Background/objectives: This study aimed to establish a mother and child cohort in the Chinese population, and investigate human breastmilk (HBM) composition and its relationship with maternal body mass index (BMI) and infant growth during the first 3 mon of life.

Subjects/methods: A total of 101 Chinese mother and infant pairs were included in this prospective cohort. Alterations in the milk macronutrients of Chinese mothers at 1 mon (T1), 2 mon (T2), and 3 mon (T3) lactation were analyzed. HBM fatty acid (FA) profiles were measured by gas chromatography (GC), and HBM proteomic profiling was achieved by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS).

Results: During the first 3 mon of lactation (P < 0.05), significant decreases were determined in the levels of total energy, fat, protein, and osteopontin (OPN), as well as ratios of long-chain saturated FA (including C16:0, C22:0 and C24:0), monounsaturated FA (including C16:1), and n-6 poly unsaturated FA (PUFA) (including C20:3n-6 and C20:4n-6, and n-6/n-3). Conversely, butyrate, C6:0 and n-3 PUFA C18:3n-3 (α-linolenic acid, ALA) were significantly increased during the first 3 mon (P < 0.05). HBM proteomic analyses distinguished compositional protein differences over time (P = 0.001). Personalized mother-infant analyses demonstrated that HBM from high BMI mothers presented increased total energy, fat, protein and OPN, and increased content of n-6 PUFA (including C18:3n-6, C20:3n-6 and n-6/n-3 ratio) as compared with low BMI mothers (P < 0.05). Furthermore, BMI of the mothers positively correlated with the head circumference (HC) of infants as well as the specific n-6 PUFA C20:3n-6 over the 3 time points examined. Infant HC was negatively associated with C18:0.

Conclusion: This study provides additional evidence to the Chinese HBM database, and further knowledge of FA function. It also helps to establish future maternal strategies that support the healthy growth and development of Chinese infants.

Keywords: Humans; body mass index; breast feeding; fatty acids; growth; milk.

Fig. 1. Shifts in human milk nutrient concentrations during the first 3 mon of lactation: total energy (A), fat (B), total fatty acid (C), carbohydrate (D), total protein (E), and OPN (F).

All values are represented as mean ± SD (n = 101). OPN, osteopontin; T1, 1 mon; T2, 2 mon; T3, 3 mon. ^*P < 0.05 (analysis of variance and the Bonferroni post hoc test).

Fig. 2. (A, B) Principal coordinate analysis for the human milk protein profiling at T1 (blue dots), T2 (red dots) and T3 (yellow dots). The polypeptide profiling of T1 significantly differs from T2 and T3 (n = 101).

T1, 1 mon; T2, 2 mon; T3, 3 mon. ^*P < 0.05.

Fig. 3. Comparison of the head circumference (A), body length (B), body weight (C) and weight/length score (D) of infants born to normal weight and overweight mothers, at T1, T2 and T3. All values are represented as mean ± SD (n = 23–25/group).

BMI, body mass index; T1, 1 mon; T2, 2 mon; T3, 3 mon. ^*P < 0.05 (Independent t-test).

Fig. 4. Comparison of the total energy (A), fat (B), total fatty acid (C), carbohydrate (D), total protein (E) and OPN (F) in breast milk of normal weight and overweight mothers during the first 3 mon of lactation. All values are represented as mean ± SD (n = 23–25/group).

OPN, osteopontin; T1, 1 mon; T2, 2 mon; T3, 3 mon. ^*P < 0.05 (Independent t-test).

Fig. 5. Correlation between maternal BMI and infant HC at T1, T2, and T3, examined by Pearson correlation analysis after adjustment for potential confounders: maternal age, delivery pattern, and sex of child. The correlation between HBM FAs with maternal BMI or infant HC at T1, T2, and T3, examined by Spearman's rank analysis after adjustment for potential confounders: maternal age, delivery pattern, and sex of child (n = 101).

(A) Correlation between maternal BMI and infant HC at T1, T2, and T3. (B) Correlation between maternal BMI and C20:3n-6, C18:3n-6 and butyrate at T1. (C) Correlation between maternal BMI and C20:3n-6, C18:3n-6, C18:1 and total MUFA at T2. (D) Correlation between maternal BMI and C20:3n-6, n-6/n-3, n-3 PUFA, and C18:3n-3 at T3. (E) Correlation between infant HC and C18:0 at T2 and T3, and inversely correlated with C20:3n-3,C20:5n-3 at T3. BMI, body mass index; HC, head circumference; HBM, human breast milk; FA, fatty acids; MUFA, monounsaturated fatty acid; PUFA, poly unsaturated fatty acids; T1, 1 mon; T2, 2 mon; T3, 3 mon.