title: Calcium bioavailability from a calcium-rich mineral water, with some observations on method.
abstract: OBJECTIVE
  The study was designed to determine whether high-calcium mineral water is an efficient additional source of dietary calcium, optimizing a method for calcium determination never used for mineral waters.
  
  
  BACKGROUND
  It is generally agreed that an adequate calcium intake is necessary for the acquisition of an ideal peak bone mass and for the maintenance of the bone mineral density in adults, in postmenopausal women, and in the elderly. Mineral waters are calorie free, and some, with high calcium levels, might be significant sources of calcium.
  
  
  METHODS
  The availability of the calcium contained in a high-calcium mineral water was measured in 27 healthy subjects. In 8 subjects the calcium availability of the water was compared with the calcium availability ingested with milk at the same calcium load. Milk and water were labeled extrinsically with 30 mg Ca. Fractional absorption from the oral dose was determined from plasma samples using ICP-MS technique.
  
  
  RESULTS
  At an ingested calcium load of 3.18 mmol, percentage of absorption for water averaged 22.53 +/- 2.53 (mean +/- SD) for men, 22.57 +/- 2.10 (mean +/- SD) for premenopausal women and 21.62 +/- 3.12 (mean +/- SD) for postmenopausal women. Percentage absorption from milk was 23.15 +/- 4.06 (mean +/- SD).
  
  
  CONCLUSIONS
  The calcium from the mineral water is thus highly bioavailable, at least as bioavailable as milk calcium, and ICP-MS appears to represent a reliable and reproducible method for calcium absorption from alimentary sources.
authors.affiliation: Department of Internal Medicine, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Bacciottini
authors.forename: Annalisa
authors.initials: A
authors.lastname: Tanini
authors.forename: Alberto
authors.initials: A
authors.lastname: Falchetti
authors.forename: Laura
authors.initials: L
authors.lastname: Masi
authors.forename: Francesco
authors.initials: F
authors.lastname: Franceschelli
authors.forename: Barbara
authors.initials: B
authors.lastname: Pampaloni
authors.forename: Gianluca
authors.initials: G
authors.lastname: Giorgi
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Brandi
mesh_terms: D000328:Adult; D000465:Algorithms; D001682:Biological Availability; D002118:Calcium / Q000097:blood / Q000493:pharmacokinetics*; D002127:Calcium Isotopes; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D008900:Mineral Waters / Q000008:administration & dosage*; D012737:Sex Factors
chemical_list: D002127:Calcium Isotopes; D008900:Mineral Waters; D002118:Calcium