Effect of lactulose on calcium and magnesium absorption: a study using stable isotopes in adult men.
To evaluate the effect of lactulose on calcium (Ca) and magnesium (Mg) absorption, we performed a clinical trial with a double-blind, randomized, crossover design in 24 healthy adult male volunteers. The absorptions of Ca and Mg were evaluated by a single-labeling method using stable isotopes. The test foods, containing lactulose at a dose of 0 g (placebo), 2 g (low-dose), or 4 g (high-dose) together with 300 mg of Ca containing 20 mg of 44Ca, and 150 mg of Mg containing 28 mg of 25Mg, were administered orally. Urine samples were collected for 8 h after the ingestion of the test food. The ratios of stable isotopes in urine (44Ca/40Ca and 25Mg/24Mg) were measured by ICP-MS (inductively coupled plasma-mass spectrometry). The urinary stable-isotopes ratios (44Ca/40Ca and 25Mg/24Mg) increased with lactulose dosage. Significant differences were observed in the Ca ratio between placebo and high-dose lactulose (p<0.01), and in the Mg ratio between placebo and low-dose lactulose and between placebo and high-dose lactulose (p<0.01). Lactulose ingestion did not change the levels of bone-resorption markers (type I collagen cross-linked N-telopeptide and deoxypyridinoline) in urine. The test foods did not cause any side effects. This study demonstrates that lactulose enhances the absorptions of Ca and Mg in adult men.
Seki
Nobuo
N
Food Research & Development Laboratory, Morinaga Milk Industry Co., Ltd., Zama, Kanagawa 228-8583, Japan. n_seki@morinagamilk.co.jp
Hamano
Hirokazu
H
Iiyama
Yuriko
Y
Asano
Yuzo
Y
Kokubo
Sadayuki
S
Yamauchi
Koji
K
Tamura
Yoshitaka
Y
Uenishi
Kazuhiro
K
Kudou
Hideki
H
D000328:Adult; D000596:Amino Acids / Q000187:drug effects / Q000652:urine; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood / Q000652:urine; D016723:Bone Remodeling / Q000187:drug effects; D002118:Calcium / Q000008:administration & dosage* / Q000378:metabolism* / Q000652:urine; D002127:Calcium Isotopes / Q000008:administration & dosage / Q000652:urine; D024042:Collagen Type I / Q000187:drug effects / Q000652:urine; D003404:Creatinine / Q000652:urine; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D005765:Gastrointestinal Agents / Q000008:administration & dosage*; D006801:Humans; D007408:Intestinal Absorption / Q000187:drug effects*; D007792:Lactulose / Q000008:administration & dosage*; D008274:Magnesium / Q000008:administration & dosage* / Q000378:metabolism* / Q000652:urine; D008297:Male; D013058:Mass Spectrometry; D010455:Peptides / Q000187:drug effects / Q000652:urine; D012016:Reference Values
D000596:Amino Acids; D015415:Biomarkers; D002127:Calcium Isotopes; D024042:Collagen Type I; D005765:Gastrointestinal Agents; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D007792:Lactulose; C036020:deoxypyridinoline; D003404:Creatinine; D008274:Magnesium; D002118:Calcium