Vitamin B12 absorption from the gut does not decline with age in normal elderly humans.

In 37 elderly subjects undergoing measurement of whole body retention of 58Co-B12 at 7 and/or 14 days it was observed that significant (greater than 5%) retention of an inert non-absorbable marker (51CrCl3) occurred at 7 days in 23% of subjects and at 14 days in 8% of subjects. In view of the substantial retention of marker at 7 days it is suggested, therefore, that 14-day measurements of B12 retention are more appropriate than 7-day measurements in the elderly. Whole body retention of vitamin B12 at 14 days was measured in 51 healthy elderly subjects. Results obtained did not correlate with age, between 60 and 96 years, and were no different from results obtained from younger subjects in previously reported studies. It is concluded that vitamin B12 absorption, per se, does not decline with age.