Breast milk provides inadequate amounts of vitamin B12 for predominantly breastfed Guatemalan infants

Authors: ANAYA-LOYOLA, MIRIAM - Autonomous University Of Queretaro; BRITO, ALEX - First Moscow State Medical University; BROWN, KENNETH - Gates Foundation; Allen, Lindsay - A

Submitted to: International Journal for Vitamin and Nutrition Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2018
Publication Date: 4/16/2019
Citation: Anaya-Loyola, M.A., Brito, A., Brown, K.H., Allen, L.H. 2019. Breast milk provides inadequate amounts of vitamin B12 for predominantly breastfed Guatemalan infants. International Journal for Vitamin and Nutrition Research. 90(5-6):395-402. https://doi.org/10.1024/0300-9831/a000583.
DOI: https://doi.org/10.1024/0300-9831/a000583

Interpretive Summary: Vitamin B12 (B12) is essential for the development and function of the brain and nervous system, and adequate B12 status is especially important for the normal development of infants. In our previous research in Guatemala City we reported a high prevalence of B12 deficiency in lactating women and their infants at 3 and 12 months of age, and low B12 concentrations in breast milk. The purpose of the current study was to assess factors associated with the serum B12 concentration of predominantly breastfed Guatemalan infants, including their intake of B12 from breast milk and other foods. Serum B12, breast milk and other food intakes, anthropometry, morbidity and socioeconomic status were assessed in infants 6.7±0.6 months of age (n=127, 52% female) in peri-urban Guatemala City. Twenty-four percent of infants had deficient B12 status (serum B12 concentration<148 pmol/L) and 37% had marginal B12 status (148-220 pmol/L). Serum B12 concentrations were significantly lower in infants who typically consumed more breast milk (r=-0.37, p=0.001), and higher in those whose total consumption of animal source foods, especially cow’s milk, was higher (r=0.40, p=0.001). Based on previously analyzed breast milk B12 concentrations in a nearby community, breast milk provided <10% of the recommended daily B12 intake for this age. We conclude that there was a high prevalence of B12 deficiency in these Guatemalan infants by 6 months of age. Serum B12 was higher and more adequate in infants consuming more cow’s milk and lowest in those consuming more breast milk, reflecting the low B12 in the latter.

Technical Abstract: Vitamin B12 (B12) plays in an important role in the development and function of the brain and nervous system, and adequate B12 status is especially important for the normal development of infants. In previous research conducted in Guatemala City we reported a high prevalence of B12 deficiency in lactating women and their infants 3 and 12 months of age, and low B12 concentrations in breast milk. The objective of this study was to assess predictors of serum B12 concentration in predominantly breastfed Guatemalan infants including intake of B12 from breast milk and other foods. Serum B12, breast milk and other food intakes, anthropometry, morbidity and socioeconomic status were assessed in infants 6.7±0.6 months of age (n=127, 52% female) in peri-urban Guatemala City. Twenty-four percent of infants had deficient B12 status (serum B12 concentration<148 pmol/L) and 37% had marginal B12 status (148-220 pmol/L). Serum B12 concentrations were negatively correlated with infants’ consumption of energy from breast milk (r=-0.37, p=0.001), and positively correlated with their total consumption of animal source foods, especially cow’s milk (r=0.40, p=0.001). Based on previously analyzed breast milk B12 concentrations in a nearby community, breast milk provided <10% of the recommended daily B12 intake for this age. We conclude that there was a high prevalence of B12 deficiency in these Guatemalan infants by 6 months of age. Serum B12 was higher and more adequate in infants consuming more cow’s milk and lower in those consuming more breast milk, reflecting the inadequacy of breast milk to meet requirements.