Vitamin B12 Absorption from Fish

Publisher Website
Google Scholar
Abstract
The main purpose of this investigation was to study the assimilation of cyanocobalamin from fish. For this reason rainbow trout were injected with 57Co-vitamin B12 and sacrificed 2 to 3 weeks later. The radioactivity was found to be evenly distributed in the muscle mass. In contrast to findings in birds and mammals the liver contained on the average less radioactivity than did the kidneys, head, skin, and muscle mass. The radiolabeled fish was ingested by three healthy subjects in 50- to 300-g portions and the absorption measured by the stool excretion method. The study shows that from an average of 2.07 μg of vitamin B12 (50 g of fish), 4.05 μg (100 g), 9.2 μg (200 g), and 13.3 μg (300 g) the assimilation of cobalamin averaged 0.87, 1.55. 3.90, and 3.98 μg, respectively. In two of the subjects, an upper limit of absorption was reached, while in one it was still climbing. A standard urinary excretion test using 100 g of fish, eaten by healthy subjects and by patients who presented with low serum vitamin B12 levels, showed very low absorption values after the fish and after the crystalline radio-cyanocobalamin in patients with pernicious anemia. Subnormal assimilation of cobalamin from the fish with normal absorption of crystalline radio-B12 was noted in subjects with simple gastric achlorhydria and in patients who had undergone partial gastrectomy.