Table 2.  Changes in the concentrations of fasting plasma glucose (FPG), insulin, glycated hemoglobin (HbA_1c), glycated albumin (GA), and 1,5‐anhydroglucitol (1,5AG) during the 12‐week supplementation with mulberry leaf extract (6 mg 1‐deoxynojirimycin, thrice daily) or placebo followed by 4‐week observation without supplementation (study 2).

Parameter/Group	Baseline	Week 4	Week 8	Week 12	Posttreatment observation (week 16)	P*
FPG (mg/dL)
Mulberry leaf extract	114 ± 7	115 ± 10	112 ± 10	114 ± 11	117 ± 10	0.326
Placebo	115 ± 6	114 ± 9	114 ± 8	112 ± 12	115 ± 9
Insulin (μU/mL)
Mulberry leaf extract	7.2 ± 3.7	7.4 ± 3.6	6.8 ± 2.9	7.3 ± 5.1	8.3 ± 7.5	0.740
Placebo	7.0 ± 3.4	7.0 ± 3.4	6.8 ± 2.9	6.7 ± 3.3	7.0 ± 3.9
HbA1c (%)
Mulberry leaf extract	6.0 ± 0.4	5.9 ± 0.3†	5.9 ± 0.3†	5.8 ± 0.4†	5.8 ± 0.4†	0.687
Placebo	5.9 ± 0.4	5.8 ± 0.4†	5.9 ± 0.4	5.8 ± 0.4†	5.8 ± 0.4†
GA (%)
Mulberry leaf extract	16.9 ± 1.6	16.8 ± 1.5	16.5 ± 1.5†	16.5 ± 1.5†	16.2 ± 1.5†	0.608
Placebo	17.1 ± 1.8	17.1 ± 1.8	16.8 ± 1.7†	16.7 ± 1.8	16.5 ± 1.8†
1,5AG (μg/mL)
Mulberry leaf extract	17.5 ± 6.0	19.6 ± 6.4†	21.0 ± 6.2†,‡	20.5 ± 6.7†,‡	18.5 ± 6.6	<0.001
Placebo	17.0 ± 5.6	17.2 ± 5.3	17.7 ± 5.5	17.4 ± 5.6	17.1 ± 5.5

Data are mean ± SD (n = 33 in the extract group, n = 32 in the placebo group). *Two‐way anova, group × time interaction. †Significantly different from the baseline value (P < 0.05 with Bonferroni correction). ‡Significantly different compared with the placebo value at each time point (P < 0.05 by unpaired t‐test).