DIETARY-INTAKE OF COBALAMIN IN ELDERLY PEOPLE WHO HAVE ABNORMAL SERUMCOBALAMIN, METHYLMALONIC ACID AND HOMOCYSTEINE LEVELS

Objective: To determine if poor dietary intake can explain the cobalam in-related abnormalities often seen in the elderly. Design: Prospectiv e laboratory survey with a follow-up dietary assessment. Setting: Soci al centers for the elderly and an outpatient clinic. Subjects: Ninety- five free-living subjects >60 y old with abnormal or suspicious findin gs in cobalamin-related tests and 78 subjects >60 y old with normal re sults. Interventions: Serum cobalamin, methylmalonic acid and homocyst eine determinations to assess cobalamin status and a one year food-fre quency questionnaire to assess cobalamin intake. Results: Only three o f the 173 subjects (1.7%), one of whom had normal cobalamin status, in gested <2 pg cobalamin/d, the Recommended Daily Allowance. Sixty-nine subjects (39.9%) ingested <6 mu g/d, but they did not have more abnorm al serum cobalamin or metabolite values than those ingesting >6 mu g. Ordering all subjects by quintiles according to cobalamin intake revea led no significant trends or differences in any of the serum values ei ther. Moreover, arranging subjects by results of tests of cobalamin st atus showed that the subjects with abnormal cobalamin status did not d iffer in cobalamin intake from those with normal cobalamin status, alt hough they did differ in use of supplements. Finally, cobalamin intake , with or without supplements, did not correlate with serum cobalamin or metabolite levels. The absence of any association between cobalamin status and intake contrasts sharply with the significant correlation between folate intake and folate status (P = 0.0001). Conclusions: The high Frequency of mildly abnormal cobalamin status in the elderly can not be attributed to poor intake of cobalamin. Nondietary explanations , such as malabsorption and other phenomena, must always be sought to explain mild cobalamin deficiency in the elderly.