Diabetes is a growing worldwide epidemic. Approximately 29.1 million people in the U.S. are living with diabetes, according to a 2014 Centers for Disease Control and Prevention report. Increased blood sugar levels that occur with diabetes can damage vital organs and nerves. The recommended mainstays for diabetes treatment are blood-sugar-lowering medications, a healthy diet and regular exercise. Many people are also interested in natural remedies such as tamarind, a small pod-like fruit. The fruit pulp and seeds are the main medicinal parts, but the leaves and the bark of the tree are also used as folk medicines. Some preliminary evidence from animal and laboratory studies indicate that tamarind might have beneficial effects for diabetes -- but tamarind has not yet been studied in humans, so whether it might be useful for people with diabetes remains uncertain.
Blood Sugar Effects
A February 2014 article in the "Pakistan Journal of Biological Sciences" reported on the effects of an extract of tamarind tree bark on blood sugar levels in rats. In one experiment, rats were pretreated to artificially elevate their blood sugar levels. Tamarind bark extract was then administered and was found to substantially reduce blood sugar levels in the test rats. In a second experiment, tamarind bark extract was administered to rats, followed by a large amount of sugar. The bark extract blunted increases in blood sugar in the test rats. While these preliminary animal experiments are promising, it's important to note that tamarind bark extract has not been tested in people. To date, little to no documented research has been performed to determine whether tamarind fruit, seeds or bark extract might benefit people with diabetes.
Oxidative stress refers to a chemical imbalance in the body caused by excess accumulation of substances called free radicals. Oxidative stress can damage body tissues, such as the insulin-producing cells of the pancreas. It's also a contributing factor to the development and progression of diabetes. Antioxidants neutralize free radicals, reducing oxidative stress and protecting tissues from related damage.
A study published in the April-June 2014 issue of "Pharmacognosy Research" showed that an extract of ground tamarind seeds had antioxidant effects in the laboratory. A March-April "British Journal of Diabetes and Vascular Disease" analysis of relevant medical research suggests that supplementation with strong antioxidants like vitamins C and E might help control blood sugar levels by combating oxidative stress. However, no studies have been conducted to determine whether any tamarind products might have similar effects in people with diabetes.
Diabetes can damage the kidneys over time. One of the first signs of diabetes-related kidney damage is leakage of blood proteins into the urine. A study published in the November-December 2013 issue of "Acta Poloniae Pharmaceutica" tested the effects of tamarind bark extract on diabetic rats. In addition to inducing lower blood sugar levels, rats treated with the extract were found to have blood protein levels that suggested less protein leakage from the kidneys. The authors concluded this may have been from a protective effect of tamarind bark extract on the kidneys. Again, these findings are potentially encouraging. But it remains unknown whether any tamarind product might have beneficial effects on kidney function in people with diabetes, because this has never been studied.
Warnings and Precautions
Although tamarind bark and seed extracts have been shown to have beneficial effects in a few laboratory and animal studies, human research is still lacking. This makes it impossible to know whether tamarind fruit, seeds or bark extract might be helpful for people with diabetes. Tamarind is not a replacement for diabetes medications, and it's important to not stop or change your diabetes medication dosages without your doctor's approval. Talk with your healthcare provider before using any natural remedy for your diabetes to be sure it's safe, and to avoid any interactions with medicines you may be taking or other harmful effects.
Side effects of tamarind consumption are uncommon but may include indigestion and possible erosion of the teeth from long-term use because of its high acid content. In addition, blood levels of ibuprofen (Advil, Motrin) and aspirin can increase when taken with tamarind, possibly causing overdose symptoms and increased bruising.
- Centers for Disease Control and Prevention: National Diabetes Statistics Report, 2014
- Pakistani Journal of Biological Sciences: Antihyperglycaemic Activity of The Stem-Bark Extract of Tamarindus Indica L. on Experimentally Induced Hyperglycaemic and Normoglycaemic Wistar Rats
- Pharmacognosy Research: Comparative Study of Antidiabetic Activity of Cajanus Cajan and Tamarindus Indica in Alloxan-Induced Diabetic Mice With a Reference to In Vitro Antioxidant Activity
- Acta Poloniae Pharmaceutica: Effect of Tamarindus Indica Linn. and Cassia Fistula Linn. Stem Bark Extracts on Oxidative Stress and Diabetic Conditions
- Asian Pacific Journal of Tropical Biomedicine: Tamarindus Indica and Its Health Related Effects
- British Journal of Diabetes and Vascular Disease: Dietary Antioxidant Interventions in Type 2 Diabetes Patients: A Meta-Analysis