Effect of hypochlorhydria due to omeprazole treatment or atrophic gastritis on protein-bound vitamin B12 absorption.
OBJECTIVE
To investigate the effects of hypochlorhydria and acidic drink ingestion on protein-bound vitamin B12 absorption in elderly subjects.


METHODS
Absorption of protein-bound vitamin B12 was examined in elderly normal subjects (n = 8), and in hypochlorhydric subjects due to omeprazole treatment (n = 8) or with atrophic gastritis (n = 3). Subjects underwent absorption tests of protein-bound vitamin B12 ingested with water, cranberry juice and 0.1 N hydrochloric acid.


RESULTS
Protein-bound vitamin B12 absorption was lower in the omeprazole-treated group (0.50%) compared to the normal group (1.21%; p < 0.001). With cranberry juice ingestion, the omeprazole-treated group showed an increase in absorbed protein-bound vitamin B12 (p = 0.025). With dilute hydrochloric acid ingestion, there was a further increase in vitamin B12 absorption (p < 0.001).


CONCLUSIONS
Omeprazole causes protein-bound vitamin B12 malabsorption, and ingestion of an acidic drink improves protein-bound vitamin B12 absorption.
Saltzman
J R
JR
USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA.
Kemp
J A
JA
Golner
B B
BB
Pedrosa
M C
MC
Dallal
G E
GE
Russell
R M
RM
D000042:Absorption; D000126:Achlorhydria / Q000139:chemically induced* / Q000209:etiology* / Q000503:physiopathology; D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005744:Gastric Acid / Q000378:metabolism; D005745:Gastric Acidity Determination; D005757:Gastritis, Atrophic / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D006851:Hydrochloric Acid / Q000008:administration & dosage / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008297:Male; D009853:Omeprazole / Q000009:adverse effects* / Q000627:therapeutic use; D010435:Pepsinogens / Q000097:blood; D011485:Protein Binding; D011863:Radioimmunoassay; D014805:Vitamin B 12 / Q000493:pharmacokinetics*
D010435:Pepsinogens; D009853:Omeprazole; D014805:Vitamin B 12; D006851:Hydrochloric Acid