Reducing effect of calcium in combination with magnesium and lactulose on body fat mass in middle-aged Japanese women.

BACKGROUND It has been reported that adequate calcium intake decreases body fat and appropriate intakes of magnesium suppress the development of the metabolic syndrome. Furthermore, lactulose increases the absorption of calcium and magnesium. An optimal combination of calcium, magnesium and lactulose may therefore reduce body fat mass. METHODS An open-label randomized controlled trial was conducted to investigate the body fat-reducing effects of a test food containing 300 mg calcium, 150 mg magnesium, and 4.0 g lactulose. Body composition parameters and blood hormone and urine mineral concentrations were measured at baseline and at 6 and 12 months thereafter. Whole-body fat mass was measured with dual-energy x-ray absorptiometry. RESULTS Seventy-six middle-aged Japanese women (47.5±4.7 years) were randomized to the intake group (n=48) or the non-intake control group (n=28). At 12 months the difference in body fat mass change between the two groups (intake group - control group) was -0.8 kg (95% CI: -1.5 - 0.0 kg, p=0.046), although there were no differences in anthropometric data between the two groups. Body fat percentage at 12 months tended to be lower in the intake group, but the difference was not significant (p=0.09). CONCLUSIONS These findings may suggest that calcium in combination with magnesium and lactulose can reduce body fat mass in middle-aged Japanese women. However, the contribution of magnesium and lactulose are unclear in this study. Further studies are needed to clarify these contributions.