Figure 2: The effects of Mg:Ca ratio on changes of Δ13C values in subjects with a successful outcome. The Δ13C values were compared between "before" and "after" drinking test water. Control-1, commercial water; A to E, RDSW with different Mg:Ca ratios of hardness 1000 as shown in Table 1. Bars show ±SD (standard deviation). * Significant difference was observed (p<0.01).