VITAMIN-B-12 DEFICIENCY IS VERY PREVALENT IN LACTATING GUATEMALAN WOMEN AND THEIR INFANTS AT 3 MONTHS POSTPARTUM

Vitamin B-12 status was evaluated in 113 Guatemalan women and their in fants at 3 mo of lactation. Plasma vitamin B-12 was deficient or low i n 46.7% of the mothers, and holotranscobalamin II (hole TC II) concent rations were low in 32.3%, which may indicate vitamin B-12 malabsorpti on. Only 9% had deficient or low plasma folate. Breast milk vitamin B- 12 was low in 31%, and negatively correlated with infant urinary methy lmalonic acid (UMMA, r = -0.22, P < 0.05, n = 88); UMMA was elevated i n 12.2% of the infants, indicating vitamin B-12 deficiency. Mothers of the infants with elevated UMMA had significantly lower concentrations of vitamin B-12 in their breast milk compared with mothers of infants with normal UMMA concentrations (410.7 +/- 247.7 vs, 705.3 +/- 487.5 pmol/L, P = 0.05, n = 87). Mean maternal dietary intake of vitamin B-1 2 was significantly correlated with plasma vitamin B-12 (r = 0.20, P = 0.05, n = 94) and was the main determinant of plasma vitamin B-12 in a linear regression model. Determinants of maternal hole TC II concent rations included dietary intake of vitamin B-12 and Giardia lamblia in fection. There were no statistically significant determinants of infan t UMMA concentrations, We conclude that vitamin B-12 deficiency is hig hly prevalent in these lactating women and is associated with depletio n of the vitamin in their infants. The cause of the maternal deficienc y is unknown, but malabsorption exacerbated by low dietary intake of t he vitamin is a possibility.