Terminalia Chebula (Rejuna®)

Terminalia chebula
Evidence Level
Moderate
2 Clinical Trials
5 Documented Benefits
3/5 Evidence Score

Terminalia chebula (Haritaki, Black myrobalan) is the most revered herb in Tibetan and Ayurvedic medicine — called the 'King of Herbs' in Tibetan tradition and described as the medicine that 'heals all diseases.' Its fruit is exceptionally rich in hydrolyzable tannins (chebulic acid, chebulinic acid, corilagin) and gallic acid with documented antioxidant, anti-aging, digestive, cardiovascular, and anti-glycation effects. Rejuna® (Verdure Sciences) is a standardized Terminalia chebula extract positioned specifically for healthy aging and longevity applications.

Studied Dose 500–1,000 mg/day standardized extract; Rejuna® clinical dose: 500 mg/day; traditional use: 3–5 g/day fruit powder
Active Compound Chebulic acid, chebulinic acid, corilagin, ellagic acid, and gallic acid — Rejuna® by Verdure Sciences (standardized T. chebula fruit extract)

Exceptional antioxidant capacity and cellular protection

Terminalia chebula consistently ranks among the highest antioxidant activity of any botanical tested, with ORAC values exceeding pomegranate, acai, and most berries. Chebulic acid is a particularly potent inhibitor of protein glycation — a primary driver of aging-related cellular damage and advanced glycation end-product (AGE) accumulation.

Anti-glycation and anti-aging

Chebulic acid and chebulinic acid are among the most potent natural inhibitors of protein glycation — the non-enzymatic binding of glucose to proteins that creates advanced glycation end-products (AGEs) linked to accelerated aging, diabetes complications, cardiovascular disease, and neurodegeneration. This anti-AGE mechanism is a primary differentiator of T. chebula from general antioxidants.

Digestive health and gut motility

Terminalia chebula is the foundational digestive herb in Ayurvedic medicine (tridoshic — balancing all three doshas). Clinical studies confirm improvements in constipation, bowel regularity, and gut microbiome diversity. The tannin-polyphenol profile acts as both prebiotic and astringent, improving gut barrier function.

Cardiovascular and lipid health

Clinical studies show T. chebula extract reduces total cholesterol, LDL, and triglycerides while increasing HDL. Mechanisms include HMG-CoA reductase inhibition, reduced lipid peroxidation, and improved endothelial function via antioxidant protection of vascular tissue.

Blood sugar regulation and insulin sensitivity

Hydrolyzable tannins from T. chebula inhibit alpha-glucosidase and alpha-amylase enzymes, slowing carbohydrate digestion and postprandial glucose absorption. Clinical studies show reductions in fasting blood glucose and HbA1c in diabetic and pre-diabetic populations.

1

Advanced glycation end-product (AGE) inhibition

Chebulic acid and corilagin form stable complexes with reactive carbonyl species (methylglyoxal, glyoxal) that would otherwise bind to proteins and DNA, preventing the formation of advanced glycation end-products. This carbonyl-scavenging mechanism protects proteins throughout the body from glycation-mediated structural and functional damage — a core aging mechanism.

2

Nrf2 pathway activation and endogenous antioxidant induction

Gallic acid and ellagic acid from T. chebula activate Nrf2 transcription factor, inducing expression of glutathione peroxidase, superoxide dismutase, catalase, and heme oxygenase-1 — amplifying endogenous antioxidant capacity well beyond direct free radical scavenging.

3

Alpha-glucosidase and alpha-amylase inhibition

T. chebula tannins competitively inhibit both alpha-glucosidase (intestinal glucose release) and alpha-amylase (starch digestion), producing a dual carbohydrate-blocking effect that reduces postprandial glucose excursions — complementary to metformin's mechanism and additive with other alpha-glucosidase inhibitors.

1
Rejuna® and Antioxidant Biomarkers — Clinical Study
PubMed

Open-label pilot study examining Rejuna® (500 mg/day) effects on oxidative stress biomarkers and anti-glycation markers in healthy adults with metabolic concerns for 8 weeks.

Healthy adults with elevated metabolic risk markers. 8-week pilot study.

Rejuna® supplementation significantly reduced markers of oxidative stress (8-OHdG, MDA) and protein glycation (HbA1c, serum AGEs) vs. baseline. Improved antioxidant enzyme activity (SOD, catalase). Well-tolerated.

2
Terminalia chebula and Blood Glucose in Type 2 Diabetes
PubMed

Clinical study examining T. chebula fruit extract supplementation in 60 type 2 diabetic patients over 3 months.

60 T2DM patients. 3-month supplementation.

Significant reductions in fasting blood glucose (-18%), postprandial glucose, and HbA1c. Improved lipid profile. No significant adverse effects. Supports T. chebula for metabolic health in diabetic populations.

Common Potential side effects

Generally well tolerated at standardized extract doses
High doses of whole fruit powder may cause loose stools due to tannin and laxative activity
Avoid during pregnancy — traditional use as uterine stimulant at high doses

Important Drug interactions

Antidiabetic medications — additive glucose-lowering effects; monitor blood sugar
Anticoagulants (warfarin) — gallic acid and ellagic acid may mildly affect coagulation; monitor INR
Iron supplements — tannins strongly chelate iron; take T. chebula and iron supplements at least 2 hours apart
Antihypertensive medications — mild blood pressure-lowering activity; monitor