Karela

Names and identification

Language	Name
English	Karela

How does it work?

• Insulin receptor binding: Novel insulin receptor-binding protein enhances glucose uptake and clearance by triggering insulin receptor signaling pathway.
• Polypeptide-P: Insulin-mimetic protein (resembling bovine insulin) increases insulin secretion, tissue glucose uptake, liver/muscle glycogen synthesis, and glucose oxidation while decreasing hepatic gluconeogenesis.
• Charantin: Steroidal saponin suppresses hepatic gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase; accelerates glucose metabolism via pentose phosphate pathway.
• AMPK activation: Cucurbitane glycosides and momordicosides activate AMPK pathway, stimulating GLUT4 translocation to cell membrane in muscle and adipocyte cell lines.
• PPAR modulation: Increases mRNA expression of PPARgamma in adipose tissue, improving insulin resistance. Compound K16 upregulates AMPKalpha1, GLUT4, SIRT1, and PPARalpha.
• PI3K/IRS-1 signaling: Activates insulin receptor substrate 1 and upregulates PI3K pathway, promoting GLUT-4 translocation in muscle and adipose tissue.
• Beta-cell effects: Extracts have been reported to repair damaged pancreatic beta-cells, increase insulin levels, and enhance insulin sensitivity.
• Intestinal absorption reduction: Inhibits glucosidase and suppresses disaccharidase activity, reducing glucose absorption.

Modern Research (Meta-Analysis)

Total PubMed publications found: 1789

Key Research Papers

1. Hypoglycemic efficacy and safety of Momordica charantia (bitter melon) in patients with type 2 diabetes mellitus.

Authors: Kim Soo Kyoung, Jung Jaehoon, Jung Jung Hwa et al. Journal: Complementary therapies in medicine (2020) PMID: 32951763

Momordica charantia (bitter melon) is widely used for its glucose-lowering effects. This study was conducted to assess the efficacy and safety of M. charantia as an adjuvant treatment in patients with type 2 diabetes…

Keywords: Adjuvant therapy, Hypoglycemic agents, Momordica charantia, Type 2 diabetes mellitus

2. Pharmacotherapeutic Potential of Bitter Gourd (

Authors: Adarmanabadi Seyed Mohammad Hosein Hosseini, Abadi Orod Jalali Khalil, Amiri Amirhossein et al. Journal: Journal of integrative neuroscience (2024) PMID: 38682220

Due to the growth of the elderly population, age-related neurological disorders are an increasing problem. Aging begins very gradually and later leads to several neurological issues such as lower neurotransmitter levels, oxidative stress, neuronal inflammation, and continual neuronal loss. These changes might contribute to brain disorders such as Alzheimer’s disease (AD), dementia or mild cognitive impairment, and epilepsy and glioma, and can also aggravate these disorders if they were previously present. …

Keywords: Alzheimer’s disease, Parkinson’s disease, age-related neurological diseases, bitter gourd

3. Bitter gourd (Momordica Charantia): A dietary approach to hyperglycemia.

Authors: Krawinkel Michael B, Keding Gudrun B Journal: Nutrition reviews (2006) PMID: 16910221

Bitter gourd (Momordica charantia) is a vegetable with pantropical distribution. It contains substances with antidiabetic properties such as charantin, vicine, and polypeptide-p, as well as other unspecific bioactive components such as antioxidants. Metabolic and hypoglycemic effects of bitter gourd extracts have been demonstrated in cell culture, animal, and human studies. The mechanism of action, whether it is via regulation of insulin release or altered glucose metabolism and its insulin-like effect, is still under debate. Adverse effects are also known. Nevertheless, bitter gourd has the potential to become a component of the diet or a dietary supplement for diabetic and prediabetic patients. Well-designed interdisciplinary research by nutritionists, medical doctors, and agronomists is…

4. An Update Review on the Anthelmintic Activity of Bitter Gourd,

Authors: Poolperm Sutthaya, Jiraungkoorskul Wannee Journal: Pharmacognosy reviews (2017) PMID: 28503051

Keywords: Helminth, Momordica charantia, infection, plant, traditional medicine, worm

5. Bitter Melon (

Authors: Sur Subhayan, Ray Ratna B Journal: Cancers (2020) PMID: 32726914

Cancer is the second leading cause of death worldwide. Many dietary plant products show promising anticancer effects. Bitter melon or bitter gourd (…

Keywords: Cucurbitaceae, bitter melon (Momordica charantia), cancer prevention, cancer therapy, medicinal plant, signal transduction

6. Promise of bitter melon (Momordica charantia) bioactives in cancer prevention and therapy.

Authors: Raina Komal, Kumar Dileep, Agarwal Rajesh Journal: Seminars in cancer biology (2016) PMID: 27452666

Recently, there is a paradigm shift that the whole food-derived components are not ‘idle bystanders’ but actively participate in modulating aberrant metabolic and signaling pathways in both healthy and diseased individuals. One such whole food from Cucurbitaceae family is ‘bitter melon’ (Momordica charantia, also called bitter gourd, balsam apple, etc.), which has gained an enormous attention in recent years as an alternative medicine in developed countries. The increased focus on bitter melon consumption could in part be due to several recent pre-clinical efficacy studies demonstrating bitter melon potential to target obesity/type II diabetes-associated metabolic aberrations as well as its pre-clinical anti-cancer efficacy against various malignancies. The bioassay-guided fractionations h…

Keywords: Bitter gourd, Bitter melon, Cancer chemoprevention, Momordica charantia, Phytochemicals

7. Bitter gourd (Momordica charantia) as a rich source of bioactive components to combat cancer naturally: Are we on the right track to fully unlock its potential as inhibitor of deregulated signaling pathways.

Authors: Farooqi Ammad Ahmad, Khalid Sumbul, Tahir Fatima et al. Journal: Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association (2018) PMID: 29753870

Research over decades has progressively explored pharmacological actions of bitter gourd (Momordica charantia). Biologically and pharmacologically active molecules isolated from M. charantia have shown significant anti-cancer activity in cancer cell lines and xenografted mice. In this review spotlight was set on the bioactive compounds isolated from M. charantia that effectively inhibited cancer development and progression via regulation of protein network in cancer cells. We summarize most recent high-quality research work in cancer cell lines and xenografted mice related to tumor suppressive role-play of M. charantia and its bioactive compounds. Although M. charantia mediated health promoting, anti-diabetic, hepatoprotective, anti-inflammatory effects have been extensively investigated, …

Keywords: Bioactive components, Momordica charantia, Protein network, Signaling

8. Emerging Antitumor Activities of the Bitter Melon (Momordica charantia).

Authors: Fang Evandro Fei, Froetscher Lynn, Scheibye-Knudsen Morten et al. Journal: Current protein & peptide science (2019) PMID: 29932035

Bitter melon or bitter gourd (Momordica charantia) is a common vegetable in Asia and it is distinctive for its bitter taste. As an ingredient in folk medicine, research from different laboratories in recent years supports its potential medicinal applications with anti-tumor, anti-diabetic, anti-HIV activities in both in vitro and animal studies. In this short review, we summarize herein the recent progress in the antitumor aspect of bitter melon with a focus on the underlying molecular mechanisms. Further mechanistic studies as well as clinical trials are necessary to further verify its medicinal applications…

Keywords: DNA damage, Momordica charantia, anticancer, apoptosis, bitter melon, medicinal applications.

What do recent studies show?

• Zhang X, Zhao Y, Song Y and others 2024. Effects of Momordica charantia L. supplementation on glycemic control and lipid profile in type 2 diabetes mellitus patients: A systematic review and meta-analysis of randomized controlled trials. Heliyon. PMID 38784554 · doi:10.1016/j.heliyon.2024.e31126
  Meta-analysis of RCTs found M. charantia supplementation reduced FPG, PPG, and HbA1c in T2DM patients, though evidence quality was low to very low for primary outcomes.
• Mkhize SAL, Phoswa WN, Ngubane PS and others 2025. Efficacy of Momordica charantia in glycaemic control and insulin resistance among patients with prediabetes and type 2 diabetes. A GRADE-adherent meta-analysis of randomised controlled trials. Metabolism open. PMID 41280283 · doi:10.1016/j.metop.2025.100407
  GRADE-adherent meta-analysis assessed glycemic control and insulin resistance in prediabetes and T2DM, providing the most rigorous evidence assessment to date using GRADE methodology.
• Laczkó-Zöld E, Csupor-Löffler B, Kolcsár EB and others 2023. The metabolic effect of Momordica charantia cannot be determined based on the available clinical evidence: a systematic review and meta-analysis of randomized clinical trials. Frontiers in nutrition. PMID 38274207 · doi:10.3389/fnut.2023.1200801
  Contradictory findings: concluded that the metabolic effect cannot be definitively determined from available clinical evidence. Low to very low quality evidence for primary outcomes, with sparse safety data warranting further research.
• Mes JJ, van den Belt M, van der Haar S and others 2025. Bitter gourd (Momordica charantia L.) supplementation for twelve weeks improves biomarkers of glucose homeostasis in a prediabetic population. Journal of ethnopharmacology. PMID 40199408 · doi:10.1016/j.jep.2025.119756
  Twelve-week supplementation improved glucose homeostasis biomarkers in prediabetic subjects.
• Kim B, Lee HS, Kim HJ and others 2023. Momordica charantia (bitter melon) efficacy and safety on glucose metabolism in Korean prediabetes participants: a 12-week, randomized clinical study. Food science and biotechnology. PMID 37009042 · doi:10.1007/s10068-022-01214-9
  12-week RCT in Korean prediabetic participants demonstrated that bitter melon extract reduced average fasting glucose levels with a generally safe profile and no serious adverse events.
• S P, R P, Kumar Mk L and others 2025. Molecular Docking and In Silico Predictive Analysis of Potential Herb-Drug Interactions Between Momordica charantia and Miglitol. Cureus. PMID 40568278 · doi:10.7759/cureus.84852
  In silico analysis showed charantin may enhance effects of alpha-glucosidase inhibitor miglitol, potentially resulting in postprandial hypoglycemia, necessitating careful monitoring.

Recent safety updates

• Generally safe in clinical trials: No serious adverse events reported during 12-week treatment periods in multiple RCTs.
• HYPOGLYCEMIA RISK: Major safety concern when combined with antidiabetic drugs. Extract combined with half doses of metformin or glibenclamide caused hypoglycemia greater than full doses alone.
• Drug interaction with miglitol: Charantin enhances alpha-glucosidase inhibitor effects, increasing postprandial hypoglycemia risk.
• Twice-daily dosing with metformin may induce hypoglycemia and death (observed in mice); once-daily is safer combination.
• Reported adverse effects: hypoglycemic coma and convulsions in children, reduced fertility in mice, favism-like syndrome, elevated gamma-GT and alkaline phosphatase in animals, headaches.
• Contraindicated in G6PD deficiency: May trigger favism-like hemolytic syndrome.
• Pregnancy caution: Abortifacient properties reported; avoid during pregnancy.
• Not an approved drug in any major regulatory jurisdiction.

Dosage forms and preparation

Dosage Forms: Swarasa (fresh juice), Churna (powder), Capsule, Tablet, Vati, Kvatha (decoction), Dried fruit powder

Standard Dosage: 30-50 mL fresh juice daily (fasting); 3-6 g powder twice daily; 500 mg standardized extract capsule twice daily

Optimal Timing: Fresh juice best taken early morning on empty stomach for glycemic control; powder/capsules 30 minutes before meals

Storage: Fresh juice must be refrigerated (2-8°C) and consumed within 48 hours. Dried preparations in airtight containers at 15-30°C. Protect polypeptide-p containing preparations from heat and light.

Marker Compounds: Charantin, Momordicin, Vicine, Polypeptide-p (p-insulin), Momordicoside, Cucurbitane triterpenoids, Gallic acid, Catechin

Synergistic Combinations

• Gudmar (Gymnema sylvestre) for comprehensive glycemic management
• Jamun (Syzygium cumini) seed for diabetic formulations
• Methi (Fenugreek) for insulin sensitization
• Haridra (Turmeric), traditionally combined in formulations for metabolic support
• Neem for synergistic hypoglycemic activity