Comparison
EGCG vs Semaglutide
Side-by-side of EGCG and Semaglutide. 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.
Semaglutide
Semaglutide for weight loss: GLP-1 agonist (Ozempic, Wegovy) drives 15-17% mean loss at 2.4 mg/week in STEP trials. Watch lean-mass loss.
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
Semaglutide
- •Long-acting GLP-1 receptor agonist with a ~7-day half-life that supports once-weekly subcutaneous dosing
- •STEP trials reported ~15 to 17% mean body-weight loss at 2.4 mg/week over 68 weeks in adults with obesity
- •Lowers HbA1c by ~1.0 to 1.8 percentage points in type 2 diabetes versus placebo
- •SELECT trial showed reduced major cardiovascular events in adults with prior CVD and overweight or obesity
- •Up to 25 to 40% of weight lost can be lean mass; pairing with resistance training and protein intake mitigates this
- •GI effects (nausea, vomiting, constipation) drive most discontinuations and ease with slow titration
Side-by-side
| Attribute | EGCG | Semaglutide |
|---|---|---|
| Category | natural | pharmaceutical |
| Also known as | epigallocatechin gallate, green tea extract | Ozempic, Wegovy, Rybelsus |
| Half-life (hr) ↗ | 3 | 168 |
| Typical dose (mg) ↗ | 400 | 2.4 |
| Dosing frequency | 1 to 2 times daily with food | weekly (SC); daily (oral Rybelsus) |
| Routes | oral | subcutaneous, oral |
| Onset (hr) | 1.5 | 24 |
| Peak (hr) | 2 | 72 |
| Molecular weight | 458.37 | 4113.58 |
| Molecular formula | C22H18O11 | - |
| 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. | Long-acting GLP-1 receptor agonist; potentiates glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and acts on hypothalamic satiety centers. |
| Legal status | Dietary supplement; warning labels required above 800 mg/day in some EU jurisdictions | Prescription only (FDA-approved, EMA-approved) |
| WADA status | allowed | allowed |
| DEA / Rx | Not scheduled | Rx only (not a controlled substance); FDA-approved for type 2 diabetes (2017) and chronic weight management (2021) |
| Pregnancy | Avoid high-dose extracts; moderate green tea consumption appears acceptable | Not recommended; discontinue 2 months before planned pregnancy |
| CAS | 989-51-5 | 910463-68-2 |
| PubChem CID | 65064 | 56843331 |
| Wikidata | Q307091 | Q27089394 |
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)
Semaglutide
Common side effects
- nausea
- vomiting
- diarrhea
- constipation
- decreased appetite
- injection-site reactions
- fatigue
Contraindications
- personal or family history of medullary thyroid carcinoma
- multiple endocrine neoplasia type 2
- pregnancy
- history of pancreatitis (use caution)
Interactions
- insulin: additive hypoglycemia risk; insulin dose typically reduced(major)
- sulfonylureas (glipizide, glyburide): hypoglycemia risk, sulfonylurea dose often reduced(major)
- oral medications (general): delayed gastric emptying can alter absorption kinetics(moderate)
- warfarin: monitor INR due to altered absorption(moderate)
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. Semaglutide is the right call when one of the conditionals below applies.
- → If your priority is healthspan extension, pick EGCG.
- → If your priority is cardiovascular health, pick EGCG.
- → If your priority is fat loss, pick Semaglutide.
Edge case: If you want to avoid prescription-only, EGCG is the more accessible choice.
Default choice: EGCG. Lower friction to source, and broader goal coverage. Reach for Semaglutide 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 Semaglutide?
EGCG and Semaglutide differ in category (natural vs pharmaceutical), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, EGCG or Semaglutide?
EGCG half-life is 3 hours; Semaglutide half-life is 168 hours.
Can you stack EGCG with Semaglutide?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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