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

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.

This randomized, double-blind, placebo-controlled pilot study evaluated MLE (1000mg 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.

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.

These results suggest that mulberry leaf extract may be a useful complementary mealtime glucose option for patients with DM2. ClinicalTrials.gov Identifier NCT00795704.