Breastmilk Vitamin B12 Concentration is Low among Women in Western Kenya and is Not Associated with Animal Source Food Intake or Food Insecurity

Abstract

Breastmilk (BM) vitamin B12 concentration varies with maternal diet, and may be inadequate in regions where animal source food (ASF) consumption is infrequent. Our objective was to measure B12 in mature BM, and examine associations with food insecurity (FI) and recent ASF intake.Between June and Aug 2014, 160 women 1‐6 mo postpartum (PP) in W. Kenya hand expressed BM one minute into a feed, following 90‐minutes of observed non‐breastfeeding. Vitamin B12 was measured using a competitive protein‐binding assay, which has been validated for BM. Food intake in the last week was measured using a food frequency questionnaire (FFQ). An ASF score was based on frequency of 10 items on the 7‐day FFQ (range 0‐70).Mean (SD) age, mo PP, and parity were 26 (6) yr, 3.7(1.4), and 3.7(2.0), respectively. Median (Q1,Q3) B12 concentration was 151 (78,247) pmol/L; 87% were <330 pmol/L, the estimated adequate level. Moderate FI prevalence was 34%; the ASF score ranged from 0‐30 (M (Q1,Q3) = 9 (5,13)). Controlling for age, education, parity, SES, dietary diversity and mo PP, FI and ASF score were not significantly associated with BM B12. Although not statistically significant, there was a trend for older mothers (p=0.09) to have higher BM B12.The vast majority of women had BM B12 concentrations currently considered inadequate, suggesting that ASF intake in this population may be insufficient among breastfeeding mothers. Neither FI nor frequency of ASF intake over the last week was associated with BM B12 concentration among women in W. Kenya.