Influence of maternal and socioeconomic factors on breast milk fatty acid composition in urban, low‐income families

Abstract

The lipid composition of breast milk may have a significant impact on early infant growth and cognitive development. Comprehensive breast milk data is lacking from low‐income populations in the Indian subcontinent impeding assessment of deficiencies and limiting development of maternal nutritional interventions. A single breast milk specimen was collected within 6 weeks postpartum from two low‐income maternal cohorts of exclusively breastfed infants, from Dhaka, Bangladesh (n = 683) and Kolkata, India (n = 372) and assayed for percentage composition of 26 fatty acids. Mature milk (>15 days) in Dhaka (n = 99) compared to Kolkata (n = 372) was higher in total saturated fatty acid (SFA; mean 48% vs. 44%) and disproportionately lower in ω3‐polyunsaturated fatty acid (PUFA), hence the ω6‐ and ω3‐PUFA ratio in Dhaka were almost double the value in Kolkata. In both sites, after adjusting for days of lactation, increased maternal education was associated with decreased SFA and PUFA, and increasing birth order or total pregnancies was associated with decreasing ω6‐PUFA or ω3‐PUFA by a factor of 0.95 for each birth and pregnancy. In Dhaka, household prosperity was associated with decreased SFA and PUFA and increased ω6‐ and ω3‐PUFA. Maternal height was associated with increased SFA and PUFA in Kolkata (1% increase per 1 cm), but body mass index showed no independent association with either ratio in either cohort. In summary, the socioeconomic factors of maternal education and household prosperity were associated with breast milk composition, although prosperity may only be important in higher cost of living communities. Associated maternal biological factors were height and infant birth order, but not adiposity. Further study is needed to elucidate the underlying mechanisms of these effects.

Association of breast milk gamma-linolenic acid with infant anthropometric outcomes in urban, low-income Bangladeshi families: a prospective, birth cohort study

“…Infant gestational age was estimated for a subset of the infants to distinguish fetal growth restriction from prematurity using the Dubowitz−Ballard assessment scale [16,17]. Breast milk FA assay procedures have been described previously and are reiterated in Supplementary Methods [18][19][20]. Individual breast milk fatty acids were expressed as %wt/wt of total identified FA; the FA profile of each specimen contained 26 individual FAs, listed in Supplementary Table S2.…”

Sexually Dimorphic Associations between Maternal Factors and Human Milk Hormonal Concentrations

“…Extensive evidence from animal models has shown that these compounds are likely to be active in HM and, once ingested by the infant, exert a range of physiological functions [5]. Changes in HM nutritional and hormonal composition have been well documented throughout the sequential stages of lactation [6,7], per feed [8], per day [9], across mothers with different phenotypic characteristics [10,11], socioeconomic status [12] and infants of different sex [13]. Limited studies to date [11,[14][15][16][17] have reported alterations in the HM bioactive, amino and fatty acid profiles of women with gestational diabetes mellitus (GDM) or elevated body mass index (BMI), suggesting that HM may have different nutritional and hormonal composition associated with individual maternal characteristics.…”

Multiplex genomewide association analysis of breast milk fatty acid composition extends the phenotypic association and potential selection of FADS1 variants to arachidonic acid, a critical infant micronutrient

“…A description of breast milk collection and quantification of a comprehensive panel of FAs to include saturated, monounsaturated and polyunsaturated FAs has been published for the PROVIDE study. 29 Similar sample collection and processing was adopted in CRYPTO study. A single breast milk sample from 1419 mothers (PROVIDE n=683 and CRYPTO n=736), collected within 6 weeks postpartum using a dried milk spot protocol, was assayed for 26 FAs by gas chromatography at OmegaQuant Analytics Laboratory (Sioux Falls, South Dakota, USA).…”