Herbal Extract
Tongkat Ali (Longjack) Extract
Also known as: Eurycoma longifolia, Longjack, LJ100, Pasak bumi
Tongkat Ali is a traditional Southeast Asian herb studied for potential effects on testosterone levels, sexual function, and exercise performance. Evidence suggests modest benefits in specific populations, particularly men with low testosterone, but results are mixed and often limited to branded extracts.
Primary uses
- Testosterone support
- Sexual function and libido
- Exercise performance and muscle gains
- Male fertility support
- Energy and vitality
How it works
- May increase luteinizing hormone (LH) signaling
- Potential aromatase inhibition
- Antioxidant and anti-inflammatory activity
- Possible effects on cortisol metabolism
Dosage
- Typical range
- 200-600 mg daily (of standardized extract)
- Timing
- With meals for better absorption
- With food
- Recommended; fat-soluble compounds benefit from food
- Duration
- Studies typically show effects after 4-12 weeks of consistent use; some effects may require 8+ weeks
- Special populations
- Most evidence in men; limited safety data in women and individuals under 18
Forms
- Powder extract· 70/100
- Capsule· 70/100
- Tablet· 70/100
- Standardized extract· 70/100
Safety
Common side effects
- Insomnia or sleep disturbances (especially if taken late in day)
- Mild headache
- Restlessness or increased heart rate
- Gastric upset (rare)
Contraindications
- Pregnancy and lactation (insufficient safety data)
- Hormone-sensitive conditions (breast, prostate cancer)
- Uncontrolled hypertension
- Use with caution in individuals with sleep disorders
Evidence notes
Moderate evidence from multiple RCTs showing benefits for testosterone in hypogonadal men and sexual function in some populations. Benefits for athletic performance less clear. Quality varies significantly by extract standardization; most positive studies use specific branded extracts (LJ100). Evidence is weaker in normotestosterolemic men.
Grade B: Some human trials support key claims; further confirmation needed.
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