Mulberry Leaf Extract and Blood Glucose Control in Diabetics

Randomized Double Blind Cross Over Trial to Examine the Effect of Mulberry Leaf Extract on Post Prandial Glucose in Type 2 Diabetics

Mulberry leaf teas or extracts are used as a natural remedy for diabetes in some countries. Animal studies have shown some effect of mulberry leaf extract on blood glucose. The purpose of this trial is to assess the effect of mulberry leaf extract on type 2 diabetics, by measuring blood glucose two hours after eating a meal and taking a capsule containing either mulberry leaf extract or a placebo.

Patients will participate in a double blind randomized cross over trial for 6 weeks. Four 2 weeks, half of the type 2 diabetic patients will receive mulberry leaf capsules three times per day with meals (made from Mulberry Zuccarin tablets - New Nordic, 400 mg of mulberry leaf extract per tablet) and half will receive placebo capsules. Following a one week wash out period, the treatments administered to each group will be reversed for the next 2 weeks, and data will continue to be gathered for a final wash out week. Patients will keep a diary of food, exercise, and fasting glucose each morning as well as at least one 2 hour pc glucose each day. Weight, hemoglobin A1C, liver function tests, and renal function tests will be done at baseline and at the end of the 6 weeks. As well, blood pressure will be monitored when the 2 weekly batches of medication are distributed, and at the end of the 6 weeks.

These patients receive placebo for two weeks, then 1 week washout, then two weeks of mulberry leaf extract.

These patients receive mulberry leaf extract for two weeks, then 1 week washout, then two weeks of placebo.

Mulberry leaf extract (400 mg, Mulberry Zuccarin, New Nordic) or placebo will be administered with meals to type 2 diabetics. Half the patients will receive mulberry leaf extract for the first two weeks and half will receive placebo. Following a one week wash out period, the interventions will be reversed for another 2 weeks, followed by a final wash out period. Subjects will keep diaries of food, exercise, daily fasting glucose, and at least one 2 hour pc glucose per day for the 6 weeks of the trial. Baseline renal function blood work and urine, liver function blood work, hemoglobin A1C, weight, and blood pressure will be done. These will be repeated at the end of each subject's 6 weeks in the trial. In addition, blood pressure will be checked with the distribution of the each 2 week batch of medications.

Success would be a change in pc glucose of -1.5 units (SI) greater than 70% of the time or in more than 70% of subject, and no increased incidence of hypoglycemia with the intervention

number of subjects with adverse changes in creatinine, AST, ALT, and blood pressure due to intervention

Because mulberry leaf tea has been shown to contain cadmium which can have renal or hepatotoxic effects, renal function, liver function, and blood pressure will be monitored.

Inclusion Criteria: Type 2 diabetes baseline hemoglobin A1C greater than or equal to 7.5 or fasting glucose greater than 7 (SI units) Exclusion Criteria: on insulin history of hepatic or renal disease pregnant or nursing women

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Another trial looking at a similar question (completed but not published at the time of this protocol)