Cycloastragenol (TA-65)New
A small-molecule telomerase activator derived from Astragalus membranaceus, marketed under the trademark TA-65. It is the most clinically studied telomerase-activating supplement, with the largest body of human RCT data of any commercially available product in this class.
Mechanism of Action
Cycloastragenol activates telomerase (hTERT) in select cell populations, particularly immune cells, slowing telomere attrition without the broad oncogenic activation seen with constitutive telomerase overexpression in cancer cells. In trials it has been shown to reduce the accumulation of senescent CD8+CD28- T cells, a hallmark of immunosenescence.
Dosing Protocol
5-10mg daily (as 100-250 units TA-65)mg
Standard starting dose based on research
Therapeutic Range
5
Minimum
50
Maximum
Morning, with or without food
Cycling Protocol
Published trials used continuous daily dosing for 6-12+ months without a cycling break; no evidence yet supports intermittent dosing.
Dosages are general guidelines. Individual requirements vary based on body weight, health status, and specific goals. Start with lower doses and adjust based on response.
Benefits
Primary Benefits
- Slower telomere shortening (RCT-confirmed)
- Reduced accumulation of senescent CD8+CD28- immune cells
- Immune resilience in older adults
Secondary Benefits
Safety Information
Contraindications
Do not use if any of the following apply:
- •Active cancer or history of certain hormone-sensitive cancers (theoretical concern given telomerase's role in cancer cell immortality, though no oncogenic signal has been observed in trials to date)
- •Pregnancy/breastfeeding (no safety data)
Drug/Supplement Interactions
May interact with the following. Consult a healthcare provider before combining:
Potential Side Effects
Some users may experience:
This is not a complete list of interactions or side effects. Individual responses vary. Always start with the lowest effective dose and monitor your response. Report any adverse effects to your healthcare provider.
Quality Markers
Look for these specific quality indicators when sourcing this compound:
- Standardized to cycloastragenol content (not raw Astragalus root extract)
- TA-65-branded or third-party verified potency
- Third-party heavy metal testing
Trusted Certifications
Note: Supplement quality varies dramatically between brands. Cheap supplements often contain fillers, incorrect doses, or contaminants. Investing in quality products from reputable manufacturers is essential for safety and efficacy.
Evidence Profile
Evidence Score
5/10
Moderate Evidence
Some clinical trials with positive results, emerging research
Evidence Scale
8-10
Strong
5-7
Moderate
1-4
Emerging
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