Impact of mulberry leaf extract on type 2 diabetes (Mul-DM): A randomized, placebo-controlled pilot study

Aims: Mulberry leaves have been used anecdotally in Asia to treat many disease states, including glucose abnormalities. Animal and human studies illustrate potential benefit of mulberry leaf extract (MLE) in type 2 diabetes mellitus (DM2). The purpose of this study is to evaluate the glycemic and safety effects of MLE in patients with DM2. Materials &methods: This randomized, double-blind, placebo-controlled pilot study evaluated MLE (1000 mg standardized) versus matching placebo given three times daily with meals. Patients (n = 24) were included if they had DM2 on single or combination oral therapy with a stable hemoglobin A1C (A1C). A 2-week placebo run-in (baseline) was followed by initiation of randomized medication for 3 months. Primary endpoints were change in A1C and self-monitoring blood glucoses (SMBG). Safety was also evaluated. Results: Of 24 patients enrolled, 17 patients completed the study. Post-prandial SMBG was significantly decreased at 3 months in the MLE group versus baseline (16.1%; p < 0.05). This improvement in post-prandial SMBG persisted when compared to placebo (18.2%; p < 0.05). A1C decreased from 7.30% at baseline to 6.94% in the MLE group but did not reach statistical significance (p = 0.079). There was no difference in A1C between MLE and placebo. A significant 15% increase occurred in serum creatinine when the MLE group was compared to baseline or placebo (p < 0.05 for both). There was no significant effect on weight, fasting SMBG, blood pressure, hypoglycemia, or other safety evaluation markers. Conclusions: These results suggest that mulberry leaf extract may be a useful complementary mealtime glucose option for patients with DM2.