Comparison
EGCG vs Thymosin Alpha-1
Side-by-side of EGCG and Thymosin Alpha-1. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
EGCG
EGCG supplement guide: 300-600 mg/day green tea catechin for fat loss and cardiovascular markers. Hepatotoxicity risk above 800 mg/day fasted.
Thymosin Alpha-1
Thymosin alpha-1 peptide (Zadaxin, thymalfasin): 28-amino-acid TA1 immunomodulator. Dosing, T-cell effects, hepatitis B and HCV adjunct evidence.
Effects at a glance
EGCG
- •Modest fat loss (~1.3 kg over 12 weeks) when combined with caffeine and caloric deficit
- •Small reductions in LDL cholesterol (3-6 mg/dL) and systolic blood pressure (2-3 mmHg)
- •EFSA flags hepatotoxicity risk above 800 mg/day, particularly when taken fasted
- •Bioavailability is 0.1-1.0%; gut microbiome variation drives population-variable response
- •Green tea extract typically combines EGCG with caffeine and L-theanine for additive effects
- •Reduces non-heme iron absorption when co-administered with meals
Thymosin Alpha-1
- •28-amino-acid synthetic peptide identical to thymic-derived immunomodulator
- •Approved in over 35 countries as Zadaxin for hepatitis B, hepatitis C adjunct, and immune support
- •Not FDA approved in US; compounded by 503A/503B pharmacies for off-label immune support
- •Modulates T-cell maturation, NK activity, and Th1 polarization in immunocompromised states
- •Standard label dose: 1.6 mg subcutaneously twice weekly
- •Cleanest safety profile in the peptide class with hundreds of regulated trials behind it
Side-by-side
| Attribute | EGCG | Thymosin Alpha-1 |
|---|---|---|
| Category | natural | peptide |
| Also known as | epigallocatechin gallate, green tea extract | Talpha1, Ta1, Zadaxin, Thymalfasin |
| Half-life (hr) ↗ | 3 | 2 |
| Typical dose (mg) ↗ | 400 | 1.6 |
| Dosing frequency | 1 to 2 times daily with food | 2x weekly |
| Routes | oral | subcutaneous, intramuscular |
| Onset (hr) | 1.5 | 24 |
| Peak (hr) | 2 | 168 |
| Molecular weight | 458.37 | 3108.32 |
| Molecular formula | C22H18O11 | C129H215N33O55 |
| Mechanism | Inhibits catechol-O-methyltransferase (COMT) to prolong norepinephrine signaling; activates AMPK; scavenges reactive oxygen species via gallate ester; modulates gut microbiome and pancreatic lipase activity. | Synthetic peptide modulator of innate and adaptive immunity. Promotes T-cell maturation and CD4/CD8 production, modulates Th1/Th2 balance, stimulates NK cell activity, and modulates TLR2/TLR9 signaling in dendritic cells. |
| Legal status | Dietary supplement; warning labels required above 800 mg/day in some EU jurisdictions | Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List |
| WADA status | allowed | unknown |
| DEA / Rx | Not scheduled | Rx only via international approval or US compounding (no controlled-substance schedule) |
| Pregnancy | Avoid high-dose extracts; moderate green tea consumption appears acceptable | Not recommended; insufficient data |
| CAS | 989-51-5 | 62304-98-7 |
| PubChem CID | 65064 | 16130571 |
| Wikidata | Q307091 | Q913854 |
Safety profile
EGCG
Common side effects
- nausea
- abdominal discomfort
- diarrhea
- jitteriness (with caffeine)
- sleep disruption (with caffeine)
Contraindications
- pregnancy at high-dose extracts
- active liver disease
- iron deficiency anemia (separate dosing)
Interactions
- iron supplements: reduces non-heme iron absorption; separate by 2 to 3 hours(moderate)
- anticoagulants: additive effects at high catechin doses(minor)
- beta-blockers (nadolol): reduced absorption when taken simultaneously(moderate)
- hepatotoxic supplements (high-dose niacin, kava): theoretical additive hepatotoxicity at high EGCG doses(moderate)
- stimulants and caffeine: additive thermogenic and cardiovascular effects(minor)
Thymosin Alpha-1
Common side effects
- mild injection-site irritation (rare)
- transient mild fatigue (rare)
- occasional headache (rare)
Contraindications
- pregnancy
- lactation
- active organ transplant rejection therapy
- systemic immunosuppression for autoimmune disease (relative)
- severe active autoimmune disease (caution)
Interactions
- interferon-alpha: additive immune effect; used clinically in approved combination protocols(minor)
- calcineurin inhibitors (cyclosporine, tacrolimus): theoretical destabilization of immunosuppression; avoid(major)
- antimetabolites (azathioprine, mycophenolate): theoretical destabilization of immunosuppression; avoid(major)
- vaccine administration: may augment vaccine response in elderly or immunocompromised; coordinate with clinician(minor)
Which Should You Take?
EGCG comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. Thymosin Alpha-1 is the right call when one of the conditionals below applies.
- → If your priority is metabolic health and glucose control, pick EGCG.
- → If your priority is healthspan extension, pick EGCG.
- → If your priority is immune support, pick Thymosin Alpha-1.
- → If your priority is post-training recovery, pick Thymosin Alpha-1.
Edge case: If you want to avoid Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List, EGCG is the more accessible choice.
Default choice: EGCG. Lower friction to source, and broader goal coverage. Reach for Thymosin Alpha-1 only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between EGCG and Thymosin Alpha-1?
EGCG and Thymosin Alpha-1 differ in category (natural vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, EGCG or Thymosin Alpha-1?
EGCG half-life is 3 hours; Thymosin Alpha-1 half-life is 2 hours.
Can you stack EGCG with Thymosin Alpha-1?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper