Astounding Health Benefits of Jamun (Syzygium cumini)

Dr. S.K. Hazarika

Syzygium cumini, also called Jamun, or black plum, is an excellent source of bioactive components such as flavonoids, polyphenols, antioxidants, iron, and vitamin C. The Jamun tree is a tropical evergreen blooming plant and is an important medicinal plant from the Myrtaceae family that has been used for a long time in Indian and other traditional medicines across the world. Jamun is mainly cultivated in Asian countries such as Pakistan, India, Sri Lanka, and Bangladesh. Since ancient medicine, it has been utilized to treat a variety of diseases and physiological conditions. Currently, it is mostly used as a medication to treat various metabolic issues, including diabetes, hyperlipidemia, hypertension, obesity, etc. Therefore, Jamun could serve a beneficial role against metabolic syndrome (MS). In this work, the latest available scientific literature on Jamun was collected and the clinical trials investigating its effect on diabetes, hypertension, obesity, and hyperlipidemia were analyzed to find out how Jamun could improve the symptoms and biomarkers of MS. Overall, the results of this study found a significant association of Jamun with the prevention and treatment of these biomarkers of MS. In many studies, Jamun showed pharmacological modifications not only in MS but in many other diseases as well. Currently, its utilization as a folk medicine for the treatment of patients with MS is widely acknowledged. Hence, the findings of a large number of clinical studies confirmed the ameliorating effects of Jamun against MS due to its antioxidation, antidiabetic, anti-inflammation anticarcinogenic, and hyperlipidemic effects. More research is still needed to determine and identify the Jamun compounds and to elucidate their mechanisms of action that are responsible for these astounding bioactive properties and health benefits.

Jamun (Syzygium cumini), a tropical fruit widely consumed in South Asia, has garnered significant attention for its medicinal, nutritional, and pharmacological properties. Rich in bioactive compounds, Jamun offers extensive health benefits, particularly for metabolic disorders like diabetes, dyslipidemia, hypertension, and obesity. Bioactive compounds are the result of involuntary developmental mechanisms, often triggered by specific physiological demands, facilitating beneficial processes and preventive mechanisms against various diseases through mutualistic or antagonistic interactions. In Jamun, these include flavonoids, phenolics, anthocyanins, terpenoids, tannins, and alkaloids. Anthocyanins, glucosides, ellagic acid, isoquercetin, kaempferol, and myricetin are particularly abundant in the fruit, seed, bark, leaves, and roots. These compounds are responsible for Jamun’s antioxidant, antibacterial, antidiabetic, CNS-modulating, chemopreventive, anti-inflammatory, and hepatoprotective effects. In traditional Ayurvedic medicine, Jamun is used to treat ailments such as kidney problems, diabetes, indigestion, and diarrhea. It is also employed to manage common conditions like cough, cold, asthma, allergic reactions, inflammation, and piles. Numerous studies have validated Jamun’s significant antidiabetic potential. In an experiment using treptozotocin-induced diabetic rats, oral administration of Jamun at doses of 100 mg/kg and 200 mg/kg notably reduced blood glucose levels. Notably, Jamun at 200 mg/kg, alone and combined with metformin, showed a substantial reduction in HbA1c after eight weeks. Similarly, the petroleum ether seed extract (PESE) and a herbal medication (HM-01) containing Jamun exhibited antidiabetic and antilipidemic effects in T2DM rat models. Fasting blood glucose (FBG) levels were significantly reduced after 22 days of oral administration. In another trial with Sprague Dawley rats on a high-sucrose diet, ethanolic extracts of Jamun seeds and fruits lowered blood glucose and regulated insulin levels effectively. A notable human trial involved a 38-year-old T2DM patient initially dependent on insulin (32 units/day).

A prescribed Ayurvedic combination including Jamun led to a significant drop in HbA1c from 11.1% to 5.6% over 12 weeks, with insulin being completely discontinued. Another study recorded FBG reduction by 46.67–52.67%, comparable to glibenclamide. Chemical analyses of these treatments revealed key compounds such as carbohydrates, steroids, and alkaloids, with arsenic levels within permissible limits. Moreover, a hydro-ethanolic extract of Jamun seed (100–400 mg/kg) improved beta cell function and reduced insulin resistance in diabetic rats. Hyperlipidemia, a prevalent metabolic disorder, is effectively addressed by Jamun seeds and leaves. In a 30-day study with male albino rats, groups supplemented with high-fat diets and Jamun extracts demonstrated significant reductions in total cholesterol (TC), triglycerides (TAGs), and LDL-C, while increasing HDL-C. The same extracts also lowered liver enzymes (SGOT, SGPT, ALP), highlighting hepatoprotective properties. In another trial, Jamun seed extract and HM-01 reduced TC by 25% and 23%, TAGs by 24% and 28%, LDL-C by 34% and 35%, and increased HDL-C by 14% and 22%, respectively. Human studies have corroborated these effects. In a randomized trial involving 99 T2DM patients, Jamun seed powder (10 g/day) significantly improved glycemic control and lipid profiles over 90 days. Its affordability makes it especially beneficial in rural healthcare settings. A separate study on prediabetic individuals also revealed notable improvements in TC levels following an 84-day supplementation of Jamun seed powder. Obesity is a key contributor to metabolic syndrome. Jamun supplementation (18.20–20.41% BW reduction) in diabetic rats rivaled standard medications.

A study using Jamun fruit extract (JFE; 100 mg/kg/day) for eight weeks in mice on a high-fat diet demonstrated reduced obesity, improved insulin resistance, and restoration of gut microbiota balance. JFE reversed the Firmicutes:Bacteroidetes ratio and increased short-chain fatty acids, suggesting its regulatory impact on metabolism and potential in managing obesity-related diseases. In stress-induced hypertensive Wistar rats, ethanol extracts of Jamun pulp (100–200 mg/g BW) significantly lowered blood pressure and malondialdehyde (MDA) levels, markers of oxidative stress, compared to controls. A nine-week mouse study using freeze-dried duhat (Jamun) powder showed a 50% reduction in triglycerides with 30% dietary supplementation. HDL-C levels improved by up to 45%, although total cholesterol remained unaffected. A separate study explored Jamun’s reproductive effects in MSG-exposed female rats. While the extract effectively managed dyslipidemia, it did not restore estrous cycle regularity. The multitude of pharmacological actions attributed to Jamun—ranging from glycemic and lipid control to antioxidant and anti-inflammatory properties—highlight its enormous potential as a functional food and therapeutic agent. With strong evidence from animal studies and emerging human clinical trials, Jamun stands out as a promising natural candidate in the fight against lifestyle-related disorders, particularly diabetes and obesity. Future clinical studies should aim to further validate its efficacy and standardize dosages for wider clinical application.