Search resultsThe silicon content of beer and its bioavailability in healthy volunteers
Title
The silicon content of beer and its bioavailability in healthy volunteers
Publication type
Journal Article
Year of Publication
2004
Authors
Journal
British Journal of Nutrition
Volume
91
Issue
3
Pagination
403 - 409
Date published
2004
ISBN
00071145 (ISSN)
Keywords
Adult, alcohol, article, atomic emission spectrometry, beer, bioavailability, Biological Availability, blood level, bone development, bone growth, connective tissue, controlled study, Female, fluid intake, Food Analysis, food intake, human, human experiment, Humans, ingestion, intestine absorption, male, normal human, silicic acid, silicon, statistics, tissue growth, ultrafiltration, urine, urine level, volunteer, water
Abstract
Dietary Si, as soluble orthosilicic acid (OSA), may be important for the growth and development of bone and connective tissue. Beer appears to be a major contributor to Si intake, although the Si content of beer and its bioavailability in human subjects have not been well established. Here we investigated the Si content of different beers and then estimated Si absorption from beer in healthy volunteers. The Si content of seventy-six different beers was estimated using inductively coupled plasma optical emission spectrometry and one of the beers, used in the ingestion study, was ultrafiltered to determine OSA content. Next, following the ingestion of 0.6 litres beer (22.5mg Si; 4.6% (v/v) ethanol), serum and urinary Si levels were measured in nine healthy volunteers over a 6 h period. A solution of OSA was similarly investigated as a positive control and water and 4.6% ethanol as negative controls. The mean Si level of beer was 19.2 (SD 6-6) mg/l; the median Si level was 18.0 mg/l. There was no significant difference in the Si levels of the different beers by geographical origin or type of beer. Serum and urinary Si levels increased considerably following the ingestion of beer or a solution of OSA but not with the ingestion of either 4.6% ethanol or water. The ultrafilterability of Si from beer (about 80%) and its absorption in volunteers (about 55%) was comparable with that of a solution of OSA suggesting that Si in beer is present chiefly in a monomeric form and is readily bioavailable.