Banaba, or Lagerstroemia speciosa, is a tree native to tropical Sotheast Asia. It belongs to the genus Lagerstroemia, also known as Crape Myrtle.
Almost every part of the tree offers medicinal properties. For example, the bark is often used to treat diarrhea, while its root and fruit extract are believed to have an analgesic, or pain-relieving, effect.
The leaves contain over 40 beneficial compounds, of which corosolic acid and ellagic acid stand out. Though the leaves offer a variety of benefits, their ability to lower blood sugar level appears the most potent and sought after.

Banaba is an herbal remedy extracted from the leaves of Lagerstroemia speciosa, a tree native to Southeast Asia. Long used in folk medicine, banaba is available in supplement form. Proponents claim that banaba can promote weight loss and treat a wide range of health problems.
Rich in corosolic acid (a substance found to possess blood-sugar-lowering, antioxidant, and anti-inflammatory properties), banaba also contains ellagitannins, a class of compound with antioxidant effects.
Banaba is a medium-size tree. Its leaves have been used to treat diabetes in folk medicine for centuries.
In addition to thier anti-diabetic properties, banaba leaves offer health benefits, such as antioxidant, cholesterol-lowering, and anti-obesity effects.

☆ Uses
Banaba is touted as a natural remedy for the following conditions:
● Diabetes
● High Blood Pressure
● High Cholesterol
● Kidney Disease
● Metabolic Syndrome
● Urinary Tract Infections
In addition, banaba is often marketed as a natural weight loss aid. Some proponents also suggest that banaba can aid in detox and enhance liver health.
☆ Benefits
● Diabetes – According to a 2015 report published in Frontiers in Bioscience, banaba and other natural supplements (including cinnamon, biotin, fenugreek, gensing, and alpha-lipoic acid) “have to potential to reduce the risk for type 2 diabetes in the large at-risk population..”

Findings from laboratory studies and animal-based research suggest that banaba may help control diabetes. In a study published in Diabetes Research and Clinical Practice, researchers evaluated the effect of the banaba compound corosolic acid and found that those who had ingested corosolic acid had lower blood glucose levels 90 minutes later, according to an oral glucose tolerance test.
● Help Control Blood Sugar Levels
The antidiabetic effects of banaba leaves is one reason why they’re popular. Researchers attribute this effect to several compounds, namely corosolic acid, allagitannins, and gallotanins.
Corosolic acid lowers blood sugar levels increasing insulin sensitivity, enhancing glucose uptake, and inhibiting alpha-glucosidase-an enzyme that helps digest carbs. That’s why it’s claimed to have an insulin-like effect.
Insulin is the hormone that regulates blood sugar levels. In people with type 2 diabetes, insulin resistance increases the demand for this hormone. However, the prancreas may not be able to meet those demands, resulting in high blood sugar levels.
In one study in 31 adults, those who received a capsule containing 10 mg of corosolic acid had lower blood sugar levels for 1-2 hours after performing an oral glucose tolerance test, compared with those in a control group

They promote glucose uptake by activating glucose transporter type 4 (GLUT4), a protein that transports glucose from the bloodstream into muscle and fat cells. Likewise, gallotanins seem to stimulate the trasportation of glucose into cells. It’s even hypothesized that a type of gallotanins called penta -O-galloyl-glucopyranose (PGG) has higher stimulatory activity that corosolic acid and ellagitannins.
While studies have found promising results on the anti-diabetic properties of banaba leaves, most have used a combination of herbs or compounds. Thus, further studies on the leaves alone are needed to better understand their blood sugar-lowering effects.
● Antioxidant Activity
Antioxidants are compounds that counteract the harmful effects of free radicals. These effects could otherwise negatively affect DNA, fat and protein metabolism and promote disease.

Banaba leaves can neutralize free radicals due to their high content of antioxidant like phenols and flavonoids, as well as quercetin and corosolic, gallic, and ellagic acids.
One 15-day study in rats found that 68 mg per pound (150 mg per kg) of body weight of banaba leaf extract neutralized free radicals and other reactive species while regulating levels of antioxidant enzyme.
● Weight loss
In a study published in phytotherapy Research in 2014, researchers assessed the effectiveness of a blend of plant extracts (including banaba) on weight loss. After the 12-weeks treatment period, those taking the extract blend had loss significantly more weight and body fat mass compared to those taking placebo. There was also greater reduction in waist and hip circumference.
Anti-Obesity Benefits
Obesity affects about 40-45% of American adults, and it’s a risk factor for chronic disease.
Recent studies have linked banaba leaves with anti-obesity activity, as they may inhibit adipogenesis and lipogenesis – the formation of fat cells and fat molecules, respectively.
Also, polyphenols in the leaves, such as pentagalloyglucose (PGG), may prevent fat cell precursors from transforming into mature fat cells.

Reduce Heart Disease Risk Factors
High blood cholesterol is a key risk factor for heart dosease – the leading cause of death in America and third leading cause of mortality worldwide.
Animal and human studies suggest that corosolic acid and PGG in banaba leaves may help lower blood cholesterol and triglycerides levels.
In one 10-week study in mice fed a high cholesterol diet, those treated with corosolic acid showed a 32% reduction in blood cholesterol and a 46% reduction in liver cholesterol levels, compared with a control group.
Similarly, a 10-week study in 40 adults with impaired fasting glucose found that a combination of banaba leaf and turmiric extract reduced triglyceride levels by 35% and increased HDL (good) cholesterol levels by 14%.
☆ Other Potential Benefits

● Anticancer Effects – Test-tube studies suggest that banaba leaf extract may promote the programmed cell death of lung and liver cancer cells.
● Antibacterial and Antiviral potential – The extract may protect against bacteria like Staphylococcus aureus and Bacillus megaterium, as well as viruses like the anti-human rhinovirus (HRV), a cause of the common cold.
● Antithrombotic Effect – Blood clots often lead to high blood pressure and stroke, and banaba leaf extract may help dissolve.
● Protection Against Kidney Damage – Antioxidants in the extract may protect the kidneys from damage caused by chemotheraphy drugs.
☆ Side Effects and Safety

Very little is known about the safety of using banaba in the long term. However, there is some concern that banaba may reduce blood sugar levels. A 2012 review found that banaba use was associated with mild adverse effects.
In a case report, corosolic acid was associated with acute kidney injury and lactic acidosis in person with diabetes who had impaired kidney function (and was taking a nonsteroidal anti-inflammatory drugs).
Supplements haven’t been tested for safety and due to the fact that dietary supplements are largely unregulated, the content of some products may differ from what is specified on the product level. Also keep in mind that the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has been established. Furthermore, it’s important to note that self-treating diabetes or any other condition with banaba and avoiding or delaying standard care may have serious consequences.
Reference: verywellfit.com / healthline.com