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Age related calcium requirements due to changes in absorption and utilization
1Department of Foods and Nutrition, Purdue University, West Lafayette, IN 47907-1264.
The Journal of Nutrition
|August 1, 1994
Summary
Estimated calcium needs for various age groups, particularly adolescents and adult women, are higher than current Recommended Dietary Allowances (RDAs) and typical U.S. intakes, highlighting potential dietary gaps for optimal bone health.
Area of Science:
- Nutritional Science
- Human Physiology
- Bone Metabolism
Background:
- Calcium is essential for bone health, and requirements change throughout the lifespan.
- Accurate estimation of calcium needs is crucial for preventing bone-related disorders.
- Current dietary reference intakes may not adequately reflect physiological calcium requirements.
Purpose of the Study:
- To estimate average calcium requirements across different age groups and genders.
- To compare estimated requirements with current Recommended Dietary Allowances (RDAs) and typical U.S. calcium intakes.
- To identify age- and gender-specific factors influencing calcium needs.
Main Methods:
- Utilized the factorial method, summing calcium accretion and endogenous losses adjusted for fractional absorption during growth.
- Employed calcium intakes necessary for achieving calcium balance in adults.
- Reviewed literature on calcium accretion rates, urinary losses, and absorption efficiency across the lifespan.
Main Results:
- Estimated calcium requirements exceed current RDAs for females aged 6-16 and over 30, and males aged 6-30.
- Estimated needs surpass current U.S. calcium intakes during adolescence for both sexes and for females over 11.
- Calcium requirements increase with age after growth cessation due to decreased absorption efficiency and with menopause.
Conclusions:
- Current data are insufficient for precise dietary calcium requirement definition during growth.
- Optimizing calcium retention for bone mass may require higher intakes than currently consumed.
- Achieving estimated optimal calcium intakes presents a significant challenge given typical U.S. dietary patterns.
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