Objective: The present study was undertaken to investigate the relationship between thiamin intake and its biochemical status in 60 free-living (30 male, 30 female) elderly subjects (> or = 65 years).
Design: Dietary intake was estimated using a 3-nonconsecutive-day food record. Biochemical status was assessed by measuring the stimulating effect of thiamin pyrophosphate (TPP) on transketolase activity (TPP effect) in hemolyzed erythrocytes, which is a functional test indicative of metabolic availability of thiamin.
Results: Average daily thiamin intake was above the recommended requirement (> 0.4 mg/1000 Kcal) for each gender; however, almost half of the total study population had TPP effect > 14%, suggesting thiamin deficiency. There was no correlation between thiamin intake and TPP effect.
Conclusion: These findings raise questions about the reliability of dietary intake in assessing metabolic availability of thiamin in the elderly.