Bitter Melon in Type 2 Diabetes

Type 2 diabetes (T2D) affects more than 530 million people worldwide. Disease hallmarks include high blood sugar (hyperglycemia) and insulin resistance. Uncontrolled blood sugar levels in T2D can lead to complications of the eyes, kidney, brain, and heart. 

Bitter melon has long been used as a food and in the management of blood sugar among various Caribbean, Asian, and African cultures. 

Clinical Evidence

In people with T2D, bitter melon (either the fruit, tea, or juice) was tested in several studies including the following:

-a non-blinded study where 27 patients with T2D were either given bitter melon tea or black tea after each major meal. The group who drank bitter melon tea had a significantly lower HbA1c (a test which estimates your blood sugar level over the past 2-3 months). There were no significant differences in fasting blood sugar. 

-a study of 5 T2D patients who were given 15 g of dried powdered bitter melon 3 times per day versus 7 who were given powdered fresh fruit essence over 3 weeks. Those given bitter melon showed 25% reduction in blood sugar levels hours after meals (suggesting improved insulin response); however the results were not statistically significant

-a study of 9 patients whose T2D were controlled by diet or drugs were given glucose tolerance tests after eating fried bitter melon or drinking bitter melon juice. The glucose tolerance test measures the amount of glucose that remains in your blood after fasting and then after drinking a sugary drink at fixed time points. Bitter melon juice significantly improved glucose tolerance (over the fried melon) without increasing insulin in the blood, suggesting that bitter melon’s anti diabetic effect does not involve insulin

Despite the lack of large, controlled trials of bitter melon in type 2 diabetes, evidence generated over the past 20-25 years shows that bitter melon may be used as part of a T2D management plan. 

References

Abascal K, Yarnell E. Using bitter melon to treat diabetes. Alternative & Complementary Therapies. 2005 Aug 1;11(4):179-84.

Reynaldo R, Ricardo F. An inquiry into the hypoglycemic action of Momordica charantia among type 2 diabetic patients. Philippine Journal of Internal Medicine 2001;39:213–216.