Low Serum B12 Concentrations Are Associated with Low B12 Dietary Intake But Not with Helicobacter pylori Infection or Abnormal Gastric Function in Rural Mexican Women.

Background: Gastric function, Helicobacter pylori infection, and vitamin B12 (B12) dietary intake were assessed as predictors of serum B12. Methods: H. pylori antibodies, gastric function, B12 dietary intake, and biochemical/hematological parameters were measured in 191 adult women from two rural communities in Queretaro, Mexico. Results: The overall mean serum B12 concentration was 211 +/- 117 pmol/L. The prevalences of low (<= 148 pmol/L), marginal (148 to 221 pmol/L), and adequate (>221 pmol/L) serum B12 were 28.4%, 31.1%, and 40.5%, respectively. Seventy-one percent of women tested positive for H. pylori antibodies. The prevalence of gastric function categories did not differ by serum B12 categories. The odds ratio for having low serum B12 was 2.7 (p = 0.01) for women with an intake below the estimated average requirement, 3.6 (p = 0.01) for those in the lowest tertile of total B12 intake, and 3.0 (p = 0.02) for those in the lowest tertile of B12 intake from animal source foods. Age and B12 intake were predictors of serum B12 concentrations [serum B12 (pmol/L) = 90.060 + 5.208 (B12 intake, mu g/day) + 2.989 (age, years). Conclusions: Low serum B12 concentrations were associated with low B12 dietary intake but not with H. pylori infection or abnormal gastric function in rural Mexican women.