title: [Bioavailability of dietary calcium].
abstract: Dietary calcium (Ca) is fundamental to the bone's health. Both the purport and the element bioavailability in the food need to be considered. The purpose of this work was to summarize the factors involved in Ca absorption and point out the sources with higher bioavailability. Ca is mostly absorbed in the jejunum and low pH seems to favor its absorption, which is higher during growth, gestation/lactation and Ca and phosphorus (P) deficiency, and lower with aging. The richest and best-absorbed Ca source is cow's milk and its derivatives. Other foods show high Ca concentrations but variable bioavailability: foods rich in phytates and oxalates show a smaller absorption and carbohydrate-rich foods show higher absorption. Since Ca bioavailability in other animal's milk, soymilk and some vegetables is closer to that in cow's milk, adequate amounts of these foods could be used as an alternative.
authors.affiliation: Hospital das Clínicas, Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, Botucatu, SP.
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Buzinaro
authors.forename: Renata N Alves de
authors.initials: RN
authors.lastname: Almeida
authors.forename: Gláucia M F S
authors.initials: GM
authors.lastname: Mazeto
mesh_terms: D000818:Animals; D001682:Biological Availability; D015519:Bone Density / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000493:pharmacokinetics*; D001862:Bone Resorption / Q000378:metabolism*; D002118:Calcium / Q000172:deficiency; D002119:Calcium Carbonate / Q000378:metabolism; D002136:Calcium, Dietary / Q000493:pharmacokinetics*; D004032:Diet; D005260:Female; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology*; D007774:Lactation / Q000378:metabolism; D007785:Lactose / Q000378:metabolism; D007787:Lactose Intolerance / Q000378:metabolism; D008297:Male; D008892:Milk / Q000378:metabolism; D009751:Nutritional Requirements; D010024:Osteoporosis / Q000178:diet therapy / Q000517:prevention & control; D041942:Soy Milk / Q000493:pharmacokinetics; D014675:Vegetables / Q000378:metabolism
chemical_list: D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary; D002119:Calcium Carbonate; D007785:Lactose; D002118:Calcium