Comparison
Metformin vs Omega-3 (EPA/DHA)
Side-by-side of Metformin and Omega-3 (EPA/DHA). 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.
Metformin
Metformin for longevity: biguanide mechanism of action, TAME trial status, anti-aging dosage, weight loss data, life extension evidence in non-diabetics.
Omega-3 (EPA/DHA)
Omega 3 fish oil profile: EPA/DHA marine fatty acids, 2-4 g/day cuts triglycerides 20-30%, REDUCE-IT showed 25% cardiovascular risk reduction on icosapent eth.
Effects at a glance
Metformin
- •Reduces HbA1c by ~1.0 to 1.5 percentage points in type 2 diabetes; first-line agent in major guidelines
- •DPP trial: 31% reduction in T2DM incidence in adults with prediabetes over 2.8 years
- •Suppresses hepatic gluconeogenesis via AMPK activation and complex I inhibition
- •Long-term use depletes B12; annual monitoring recommended after year 2
- •Lifespan extension in non-diabetic humans is not established; TAME trial pending
- •MASTERS trial reported blunted resistance-training hypertrophy in older adults
Omega-3 (EPA/DHA)
- •Reduces fasting triglycerides 20-50% at 2-4 g/day in hypertriglyceridemic patients
- •REDUCE-IT showed 25% relative risk reduction in major CV events at 4 g/day icosapent ethyl
- •Modest antidepressant effect (SMD ~0.40) for EPA-dominant formulations at 1-2 g/day
- •Atrial fibrillation incidence rises ~30-50% at 4 g/day; relevant for older patients with pre-existing CV disease
- •Tissue omega-3 index (RBC EPA + DHA) target ~8%; Western baseline typically 4-5%
- •Triglyceride and re-esterified triglyceride forms absorb ~70% better than ethyl esters in fasted state
Side-by-side
| Attribute | Metformin | Omega-3 (EPA/DHA) |
|---|---|---|
| Category | pharmaceutical | supplement |
| Also known as | Glucophage, Fortamet, Glumetza, dimethylbiguanide | fish oil, EPA, DHA, marine omega-3 |
| Half-life (hr) ↗ | 6 | 48 |
| Typical dose (mg) ↗ | 1500 | 2000 |
| Dosing frequency | 1 to 3 times daily with meals; XR once daily | 1 to 2 times daily with food |
| Routes | oral | oral |
| Onset (hr) | 1 | 4 |
| Peak (hr) | 2.5 | 12 |
| Molecular weight | 129.16 | 302.45 |
| Molecular formula | C4H11N5 | C20H30O2 (EPA); C22H32O2 (DHA) |
| Mechanism | Suppresses hepatic gluconeogenesis primarily via AMPK activation and complex I inhibition; modestly improves peripheral insulin sensitivity and shifts gut microbiome composition. | Substitutes arachidonic acid in membrane phospholipids, shifting eicosanoid production toward less-inflammatory 3-series prostaglandins and 5-series leukotrienes. Activates PPAR-alpha to lower hepatic VLDL/triglyceride synthesis. DHA modulates synaptic membrane fluidity and neuronal function. |
| Legal status | Prescription only (FDA approved for type 2 diabetes 1994) | Dietary supplement; prescription forms (icosapent ethyl, omega-3 acid ethyl esters) for severe hypertriglyceridemia |
| WADA status | allowed | allowed |
| DEA / Rx | Rx only (not a controlled substance) | Not scheduled |
| Pregnancy | Category B; used in gestational diabetes and PCOS per current guidance | Recommended at 200 to 600 mg DHA/day for fetal development |
| CAS | 657-24-9 | 10417-94-4 |
| PubChem CID | 4091 | 446284 |
| Wikidata | Q19484 | Q207688 |
Safety profile
Metformin
Common side effects
- nausea
- diarrhea
- abdominal discomfort
- metallic taste
- decreased appetite
- B12 depletion (long-term)
Contraindications
- eGFR below 30 mL/min/1.73m2
- acute or chronic metabolic acidosis
- severe hepatic impairment
- acute heart failure
- iodinated contrast within 48 hours
Interactions
- iodinated contrast media: renal injury risk; hold 48 hours peri-imaging(major)
- alcohol (heavy use): elevated lactic acidosis risk(major)
- cimetidine: raises metformin plasma levels via OCT2 inhibition(moderate)
- insulin and sulfonylureas: additive hypoglycemia risk in combination(moderate)
- dolutegravir: raises metformin exposure via OCT2(moderate)
Omega-3 (EPA/DHA)
Common side effects
- fishy aftertaste
- eructation (fish burps)
- mild dyspepsia
- loose stools at high doses
Contraindications
- fish allergy (use algal omega-3 alternative)
- active bleeding disorders
- scheduled surgery (discontinue 5-7 days prior)
Interactions
- warfarin and DOACs: additive antiplatelet effect at 2+ g/day; meaningful bleeding risk(moderate)
- aspirin and antiplatelet agents: additive bleeding risk at high doses(moderate)
- statins: complementary cardiovascular effects; no pharmacokinetic interaction(minor)
- antiarrhythmics: high-dose omega-3 increases AF risk; relevant in pre-existing arrhythmia(moderate)
Which Should You Take?
Omega-3 (EPA/DHA) comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Metformin is the right call when one of the conditionals below applies.
- → If your priority is metabolic health and glucose control, pick Metformin.
- → If your priority is cardiovascular health, pick Omega-3 (EPA/DHA).
- → If your priority is focus or working memory, pick Omega-3 (EPA/DHA).
Edge case: If you want to avoid prescription-only, Omega-3 (EPA/DHA) is the more accessible choice.
Default choice: Omega-3 (EPA/DHA). Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Metformin 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 Metformin and Omega-3 (EPA/DHA)?
Metformin and Omega-3 (EPA/DHA) differ in category (pharmaceutical vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Metformin or Omega-3 (EPA/DHA)?
Metformin half-life is 6 hours; Omega-3 (EPA/DHA) half-life is 48 hours.
Can you stack Metformin with Omega-3 (EPA/DHA)?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper