If you live in the southern part of the US, you are probably familiar with Lagerstroemia indica. Commonly known as crape myrtle, its colorful flowers and graceful trunks make it a popular landscaping tree.
In tropical areas of Asia, a related species, Lagerstroemia speciosa, is more than a pretty tree. Throughout this region, this plant has a long history of use in traditional medicine for a variety of ailments—including diabetes.
How Does Banaba Leaf Lower Blood Sugar?
As you know, the main problem with type 2 diabetes is elevated blood sugar due to insulin resistance.
When glucose (sugar) levels in the blood rise, your pancreas releases insulin. Insulin signals your cells to let glucose enter, where it is used to produce ATP, the energy that fuels your body. If your cells are resistant to insulin’s signals, blood sugar remains elevated.
Banaba leaf simply enhances your body’s ability to respond to insulin and move glucose into your cells. The main compound that is responsible for the effects of banaba leaf on blood sugar is corosolic acid. Corosolic acid works on several fronts to improve blood sugar control:
- Reduces insulin resistance, making it easier for glucose to move out of the bloodstream and into the cells where it is used for energy.
- Enhances the activity of GLUT4 proteins, which are involved in the transport of glucose into the cells.
- Decreases the production of glucose in the liver, which lowers blood sugar levels.
- Inhibits alpha glucosidase, an enzyme that breaks down starches and other carbohydrates, leading to a decline in blood sugar.
Studies on Banaba Leaf & Diabetes
Banaba leaf’s blood sugar benefits have been confirmed in multiple animal studies and several small human clinical trials involving patients with diabetes.
Although most of these studies reported decreases in blood sugar in the 10%–20% range, one clinical trial found that patients with type 2 diabetes who took 48 mg of a standardized banaba leaf extract daily for 15 days had a 30% reduction in blood sugar!
Banaba leaf has also been tested in combination with other natural ingredients, including berberine, chromium, and curcumin, with even more impressive results. Other clinical trials have reported enduring reductions in fasting blood glucose and A1C when banaba extract was used for longer periods, up to one year.
Virtually all the research on banaba leaf has concluded that it has an excellent safety profile and is well tolerated, even in larger doses. Plus, it gets to work quickly. Studies suggest that it begins exerting positive effects on blood sugar within 60 minutes of taking it.
Can Banaba Leaf Reverse Metabolic Syndrome?
Banaba leaf is also a promising treatment for another health challenge that may lead to both diabetes and cardiovascular disease. Metabolic syndrome is a cluster of risk factors that dramatically increases the likelihood of developing type 2 diabetes, heart disease, and stroke. These factors include:
- Abdominal obesity (large waist)
- Elevated blood pressure
- High triglycerides
- Low protective HDL cholesterol
- High or borderline-high blood sugar
In a small 2022 clinical trial, patients with metabolic syndrome were randomly assigned to take either banaba leaf supplements or a placebo for 12 weeks. When they were reevaluated, there were significant improvements in the banaba leaf group, including reductions in waist circumference, systolic blood pressure, and triglycerides plus improvements in insulin utilization.
Remarkably, in two-thirds of the participants, these changes resulted in total remission of metabolic syndrome! Although weight loss was not reported in this study, other research suggests that banaba leaf can help with weight control.
Banaba Leaf Recap
One in 10 adults in the United States has diabetes and one in three has metabolic syndrome. If you fall into either category, you should be concerned about your increased risk of heart disease, neuropathy, kidney disease, and other diabetic complications—and do everything you can to reduce that risk.
Along with weight loss, exercise, and a low-glycemic diet, banaba leaf and other natural compounds have proven benefits for the prevention and treatment of diabetes and metabolic syndrome.
Banaba leaf extract is available in several concentrations. One of the better studied is an extract standardized for 18% corosolic acid. The suggested dose is 48 mg, preferably taken in divided doses about 30 minutes before meals. For best results, use in combination with berberine, chromium, and other supplements that target insulin resistance and blood sugar control.