Fractional magnesium absorption is significantly lower in human subjects from a meal served with an oxalate-rich vegetable, spinach, as compared with a meal served with kale, a vegetable with a low oxalate content
Open Access
- 1 April 2004
- journal article
- research article
- Published by Cambridge University Press (CUP) in British Journal of Nutrition
- Vol. 91 (4), 601-606
- https://doi.org/10.1079/bjn20031081
Abstract
The aim of the present study was to evaluate Mg absorption from a test meal served with an oxalate-rich vegetable, spinach, as compared with a test meal served with a vegetable with a low oxalate content, kale. Mg absorption was measured by a stable-isotope technique based on extrinsic labelling of the test meals and faecal monitoring of the excreted isotope labels. Nine healthy adults participated in the study. The test meals were based on 100g phytate-free white bread, served with 300g spinach (6·6mmol oxalate; 0·7mmol 25Mg label added, 5·0mmol total Mg) or 300g kale (0·1mmol oxalate; 1·2mmol 26Mg label added, 4·8mmol total Mg). The test meals were served on days 1 and 3, at breakfast and lunch, using a cross-over design. The results from the present study demonstrated that apparent Mg absorption was significantly lower from the meal served with spinach (26·7 (sd 10·4) %) than the meal served with kale (36·5 (sd 11·8) %) (P=0·01). However, the lower fractional apparent Mg absorption from the test meal served with spinach can be assumed to be, at least partly, counterbalanced by the higher native Mg content of spinach as compared with kale. Although based on indirect evidence, i.e. not based on an evaluation of added (or removed) oxalic acid, the difference in Mg absorption observed in the present study is attributed to the difference in oxalic acid content between the two vegetables.Keywords
This publication has 21 references indexed in Scilit:
- Two Polyol, Low Digestible Carbohydrates Improve the Apparent Absorption of Magnesium but Not of Calcium in Healthy Young MenJournal of Nutrition, 2003
- Five-Week Intake of Short-Chain Fructo-Oligosaccharides Increases Intestinal Absorption and Status of Magnesium in Postmenopausal WomenJournal of Bone and Mineral Research, 2001
- Stable isotope labels as a tool to determine the iron absorption by Peruvian school children from a breakfast mealAnalytical and Bioanalytical Chemistry, 1997
- Isotopic exchange of ingested calcium between labeled sources. Evidence that ingested calcium does not form a common absorptive poolCalcified Tissue International, 1991
- Bioavailability of oxalic acid from spinach, sugar beet fibre and a solution of sodium oxalate consumed by female volunteersFood and Chemical Toxicology, 1989
- HPLC Method for Determination of inositol Tri‐, Tetra‐, Penta‐, and Hexaphosphates in Foods and Intestinal ContentsJournal of Food Science, 1986
- Serum magnesium levels in the United States, 1971-1974.Journal of the American College of Nutrition, 1986
- The effects of organic acids, phytates and polyphenols on the absorption of iron from vegetablesBritish Journal of Nutrition, 1983
- The composition of tea infusions examined in relation to the association between mortality and water hardnessEpidemiology and Infection, 1971
- The oxalic acid content of English dietsBritish Journal of Nutrition, 1962