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Protein-bound cobalamin absorption declines in the elderly
J D Scarlett1, H Read, K O'Dea
1Department of Haematology, Geelong Hospital, Victoria, Australia.
American Journal of Hematology
|February 1, 1992
Summary
Dietary cobalamin absorption declines with age, particularly in those over 75. This study found reduced absorption in healthy elderly individuals, limiting the test
Area of Science:
- Nutritional biochemistry
- Geriatric medicine
- Gastroenterology
Background:
- Cobalamin (vitamin B12) is essential for numerous physiological processes.
- Age-related changes can affect nutrient absorption, including cobalamin.
- Accurate assessment of cobalamin absorption is crucial for diagnosing deficiencies.
Purpose of the Study:
- To evaluate dietary cobalamin absorption in different age groups of healthy adults.
- To assess cobalamin absorption in patients with isolated low serum cobalamin concentrations.
- To investigate the relationship between cobalamin absorption, age, and serum gastrin levels.
Main Methods:
- Utilized a modified protein-bound cobalamin absorption test.
- Studied absorption in young adults, healthy elderly individuals (55-75 and >75 years), and patients with low serum cobalamin.
Main Results:
- Dietary cobalamin absorption significantly decreased in healthy adults aged 55-75 and further in those over 75.
- No significant difference in absorption was found between patients with low serum cobalamin and age-matched controls.
- Reduced cobalamin malabsorption correlated with elevated serum gastrin levels.
Conclusions:
- Cobalamin absorption naturally declines with aging.
- The modified protein-bound cobalamin absorption test has limited diagnostic utility in the elderly due to reduced absorption in healthy individuals.
- Further evaluation of absorption tests across different age groups is recommended before clinical application.
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