A calcium supplement containing poly-γ-glutamic acid increases human calcium absorption

• Published in: Nippon Nōgeikagaku Kaishi Vol. 77; no. 5; pp. 504 - 507
• Main Authors: TANIMOTO, Hiroyuki, NOZAWA, Hiroko, OKADA, Kyoko, MIYANO, Reiko, HIDESAKI, Momoe, TSUNEMATSU, Motoko, ITO, Kazuko
• Format: Journal Article
• Language: Japanese
• Published: Japan Society for Bioscience, Biotechnology, and Agrochemistry 01.05.2003
• Subjects: bone resorption marker; calcium absorption; poly-γ-glutamic acid; urinary calcium
• ISSN: 0002-1407; 1883-6844
• DOI: 10.1271/nogeikagaku1924.77.504

Poly-γ-glutamic acid (γ-PGA), the main component of natto mucilage, increases intestinal calcium (Ca) absorption by increasing soluble Ca in the intestine. In this study, we investigated the stimulatory effect of a Ca supplement containing γ-PGA (test meal) on Ca absorption by measuring urinary Ca excretion. A Ca supplement without γ-PGA was used as placebo. Thirty-one healthy volunteers (16 men and 15 women) participated in this study. Urinary Ca excretion and urinary bone resorption markers (pyridinoline and deoxypyridinoline) were monitored after ingestion of a test meal or a placebo. Urine was collected every two hours (0, 2, 4, 6, and 8 hours after intake). In the total subjects (n=31), there were no differences in urinary Ca or ΔCa from the initial value (urinary Ca at 0time) between the test meal and placebo groups. In male subjects (n=16), urinary Ca and ΔCa from the initial value of the test meal group was higher than that of the placebo group. ΔCa from the initial value of the test meal group was significantly higher. On the other hand, there were no differences in urinary bone resorption markers. In conclusion, these results suggest that the Ca supplement containing γ-PGA increases Ca absorption in humans.