Comparison
Magnesium Glycinate vs Omega-3 (EPA/DHA)
Side-by-side of Magnesium Glycinate 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.
Magnesium Glycinate
Magnesium glycinate supplement guide: chelated bisglycinate form, 200 to 400 mg dosage, sleep architecture benefits, low GI side effects, glycine co-effect.
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
Magnesium Glycinate
- •Shortens sleep onset latency in older adults and in deficient populations supplementing 200 to 400 mg elemental Mg
- •Improves subjective sleep quality scores (PSQI, ISI) modestly versus placebo over 4 to 8 weeks
- •Reduces nocturnal leg cramps and exercise-induced muscle cramping in some controlled trials
- •Lowers self-reported anxiety in mild-to-moderate cases, with smaller effect than first-line pharmacotherapy
- •Glycinate form delivers fewer GI side effects than oxide or citrate at equivalent elemental doses
- •Insufficient as a stand-alone hypertension treatment; small adjunctive blood-pressure reductions only
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 | Magnesium Glycinate | Omega-3 (EPA/DHA) |
|---|---|---|
| Category | supplement | supplement |
| Also known as | magnesium bisglycinate | fish oil, EPA, DHA, marine omega-3 |
| Half-life (hr) ↗ | 5 | 48 |
| Typical dose (mg) ↗ | 300 | 2000 |
| Dosing frequency | daily (often evening) | 1 to 2 times daily with food |
| Routes | oral | oral |
| Onset (hr) | 1 | 4 |
| Peak (hr) | - | 12 |
| Molecular weight | - | 302.45 |
| Molecular formula | - | C20H30O2 (EPA); C22H32O2 (DHA) |
| Mechanism | Magnesium acts as a cofactor for 300+ enzymes and as a voltage-dependent antagonist at NMDA receptors; glycine serves as an inhibitory neurotransmitter and co-agonist at glycine receptors. | 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 | Dietary supplement | Dietary supplement; prescription forms (icosapent ethyl, omega-3 acid ethyl esters) for severe hypertriglyceridemia |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | Not scheduled |
| Pregnancy | Generally considered acceptable at RDA doses; consult clinician | Recommended at 200 to 600 mg DHA/day for fetal development |
| CAS | 14783-68-7 | 10417-94-4 |
| PubChem CID | 84645 | 446284 |
| Wikidata | - | Q207688 |
Safety profile
Magnesium Glycinate
Common side effects
- mild GI upset at high doses
- loose stools (dose-dependent, less than with oxide/citrate forms)
Contraindications
- severe renal impairment
- myasthenia gravis
- heart block
Interactions
- tetracycline and fluoroquinolone antibiotics: magnesium chelates antibiotic, reducing absorption; separate by 2+ hours(moderate)
- bisphosphonates: reduced absorption of bisphosphonate(moderate)
- potassium-sparing diuretics: possible hypermagnesemia in renal impairment(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?
Magnesium Glycinate and Omega-3 (EPA/DHA) score evenly on the criteria we weight (goal breadth, legal accessibility, evidence depth). The conditionals below should drive the decision more than any aggregate score.
- → If your priority is sleep onset or sleep quality, pick Magnesium Glycinate.
- → If your priority is post-training recovery, pick Magnesium Glycinate.
- → If your priority is cardiovascular health, pick Omega-3 (EPA/DHA).
- → If your priority is healthspan extension, pick Omega-3 (EPA/DHA).
Edge case: Half-lives differ materially (Magnesium Glycinate ~5 hr vs Omega-3 (EPA/DHA) ~48 hr). Omega-3 (EPA/DHA) reaches steady state faster; Magnesium Glycinate is easier to dial in if tolerability is uncertain.
Default choice: either is defensible. Magnesium Glycinate edges out on goal breadth + legal accessibility; Omega-3 (EPA/DHA) is the right call if your priority sits in the goals listed 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 Magnesium Glycinate and Omega-3 (EPA/DHA)?
Magnesium Glycinate and Omega-3 (EPA/DHA) differ in category (supplement vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Magnesium Glycinate or Omega-3 (EPA/DHA)?
Magnesium Glycinate half-life is 5 hours; Omega-3 (EPA/DHA) half-life is 48 hours.
Can you stack Magnesium Glycinate 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.
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