| Literature DB >> 11160548 |
R M Russell1, H Baik, J J Kehayias.
Abstract
Nothing is directly known about the bioavailability of vitamin B-12 from dairy products or fortified grain products. We directly studied vitamin B-12 absorption from water, milk and fortified bread in adult subjects using (58)Co-labeled vitamin B-12 and a whole body gamma-ray counter/spectrophotometer. Sixteen healthy men and women over the age of 60 y with normal serum levels of vitamin B-12 and normal basal gastric acid secretion were studied. (58)Co vitamin B-12 (0.25 microg) was administered in water, milk or fortified bread to each subject along with 185 kBq (5.0 microCi) (51)Cr as a stool marker. Whole body counting was performed 30 min after ingestion of the radioactive dose and at 7 and 14 d after dosing. Mean absorptions from water, milk and fortified bread were 55, 65 and 55%, respectively, and did not differ. The high body retention of the extrinsic vitamin B-12 label from milk and bread may warrant a greater use of such fortified products in the elderly to ensure vitamin B-12 adequacy.Entities:
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Year: 2001 PMID: 11160548 DOI: 10.1093/jn/131.2.291
Source DB: PubMed Journal: J Nutr ISSN: 0022-3166 Impact factor: 4.798