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[Bioavailability of dietary calcium]
Elizabeth F Buzinaro1, Renata N Alves de Almeida, Gláucia M F S Mazeto
1Hospital das Clínicas, Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, Botucatu, SP.
Arquivos Brasileiros De Endocrinologia E Metabologia
|December 13, 2006
Summary
Dietary calcium (Ca) absorption is key for bone health, influenced by food bioavailability. Cow's milk offers the best-absorbed calcium, but other sources can be adequate alternatives.
Area of Science:
- Nutrition Science
- Bone Biology
- Mineral Metabolism
Context:
- Dietary calcium (Ca) is essential for maintaining bone health.
- Understanding Ca absorption factors and food bioavailability is crucial.
- Optimal Ca intake is vital throughout the lifespan, especially during growth and lactation.
Purpose:
- To summarize factors influencing calcium absorption.
- To identify food sources with superior calcium bioavailability.
- To provide insights into optimizing dietary calcium intake.
Summary:
- Calcium is primarily absorbed in the jejunum, with absorption enhanced by low pH, growth phases, gestation/lactation, and deficiencies in calcium and phosphorus (P).
- Absorption decreases with aging.
- Cow's milk and its derivatives are the richest and most bioavailable Ca sources.
- Phytates and oxalates in foods reduce Ca absorption, while carbohydrates enhance it.
- Alternative sources like other animal milks, soymilk, and certain vegetables offer comparable Ca bioavailability.
Impact:
- Informs dietary recommendations for calcium intake.
- Highlights the importance of food matrix effects on mineral bioavailability.
- Provides practical guidance for selecting calcium-rich foods for bone health.
- Supports strategies for preventing calcium deficiency and related bone disorders.
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