Omega-3 Fatty Acids

Marine EPA and DHA — among the most studied supplements for heart, brain, and joint health

Heart Health Brain Joints Triglycerides Inflammation

Evidence strength:

Very strong (triglycerides); Strong (heart, brain)

Overview

Omega-3 fatty acids are polyunsaturated fats essential for human health. The two most clinically relevant forms are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), found primarily in fatty fish (salmon, mackerel, sardines) and in fish oil or algal oil supplements. A third form, alpha-linolenic acid (ALA), is found in plant foods but converts poorly to EPA/DHA in the body.

Algal oil is the preferred source for vegetarians and vegans, and is equally effective at raising blood DHA levels as fish oil. High-dose prescription omega-3 preparations (e.g., icosapentaenoic acid alone) are used medically to treat severely elevated triglycerides.

Key fact for seniors DHA is a major structural component of brain cell membranes and the retina. Adequate omega-3 intake throughout life is associated with slower cognitive decline and reduced risk of age-related macular degeneration.

What the Evidence Shows

Triglyceride reduction

This is the most robustly proven effect. At doses of 2–4 g EPA+DHA per day, omega-3 supplements reliably reduce blood triglycerides by 20–50%. This effect is dose-dependent and consistent across many large trials.

Cardiovascular events

Evidence is nuanced. Observational data strongly support cardiovascular benefit. Randomised trial results are mixed. The REDUCE-IT trial (using 4 g/day pure EPA) showed a 25% reduction in major cardiovascular events in high-risk patients on statins. The STRENGTH trial (using EPA+DHA at 4 g/day) did not. Current evidence most strongly supports pure high-dose EPA in people with elevated triglycerides.

Cognitive health and dementia prevention

DHA is critical for neuronal membrane integrity. Several large trials, including VITAL-Cog, suggest that omega-3 supplementation may modestly slow cognitive decline in older adults, particularly those with low dietary fish intake at baseline.

Joint pain and inflammation

Meta-analyses confirm that 2–3 g/day of EPA+DHA reduces joint pain and morning stiffness in rheumatoid arthritis, and may reduce NSAID requirements. Evidence in osteoarthritis is more limited but promising.

Eye health

DHA is highly concentrated in the retina. Evidence from the AREDS2 trial suggests that omega-3 supplements do not further reduce the risk of age-related macular degeneration beyond the core antioxidant formula, though habitual dietary intake of omega-3 is associated with lower risk.

Dosage by Age Group

Group	Recommended Daily Intake (EPA+DHA)	Notes
General adults	250–500 mg/day	Minimum for general cardiovascular protection
Seniors — brain & heart protection	1000–2000 mg/day	Practical maintenance dose for older adults
Elevated triglycerides	2000–4000 mg/day	Under medical guidance; high-dose EPA+DHA or pure EPA
Joint pain / inflammation	2000–3000 mg/day	Requires several weeks to see effect

Choose products that clearly state the EPA and DHA content per serving, not just "fish oil" weight. Many standard fish oil capsules contain only 30% EPA+DHA by weight.

Australian brands

What to buy

Omega-3 is most commonly available as soft-gel capsules or liquid. Capsules are convenient for daily use; liquid (fish oil or flaxseed oil) suits those who need a higher dose or dislike capsules. Enteric-coated capsules reduce the fishy aftertaste — a common concern for seniors. Always check the label for the combined EPA + DHA milligrams per serve, not just the total "fish oil" weight.

Brand	Form	Typical product	Approx. cost
Blackmores	Soft-gel capsule	Omega Daily (1000 mg fish oil / 300 mg EPA+DHA, 400 caps)	$30–40
Bioglan	Soft-gel capsule (enteric-coated)	Red Krill Oil 500 mg (60 caps)	$25–32
Nordic Naturals	Soft-gel capsule / liquid	Ultimate Omega (1280 mg EPA+DHA per serve)	$40–55
Swisse	Soft-gel capsule	Wild Fish Oil 1000 mg (200 caps)	$18–24
Microgenics	Soft-gel capsule (high-strength)	Omega-3 Triple Strength 900 mg EPA+DHA (60 caps)	$22–28

Prices are approximate retail (Chemist Warehouse, Priceline, health food stores). For seniors needing 1000–2000 mg EPA+DHA daily, high-strength or concentrated capsules are more practical — fewer pills per day. Nordic Naturals is a globally recognised quality brand; Blackmores and Swisse are the most widely available in Australian supermarkets and pharmacies.

Safety & Cautions

Important cautions At doses above 3 g/day, omega-3 supplements may increase bleeding time. This is relevant before surgery or if taking anticoagulants. Fish oil supplements can also cause fishy aftertaste and GI discomfort; enteric-coated or refrigerated products help. High-dose omega-3 at ≥3 g/day may slightly raise LDL cholesterol in some individuals.

Drug interactions Combined use with warfarin or other anticoagulants (e.g., apixaban) at doses ≥3 g/day requires INR monitoring. Discuss with your prescribing physician before combining. Omega-3 may enhance the blood-pressure-lowering effect of antihypertensive medications.

Synergistic Combinations

Omega-3 + Vitamin D: Both are fat-soluble and studied together in the VITAL trial. They support immune function, cardiovascular health, and inflammation reduction through different but complementary pathways.
Omega-3 + Magnesium: Complementary cardiovascular support — omega-3 reduces triglycerides and inflammation while magnesium helps blood pressure and heart rhythm.
Omega-3 + Folate + Vitamin B12: Combined B-vitamin and omega-3 supplementation has shown additive benefit in slowing brain atrophy in older adults with mild cognitive impairment in the OPTIMA and VITACOG trials.

📚 Key Scientific References

1.Bernasconi AA et al. Effect of omega-3 fatty acids on cardiovascular outcomes: A systematic review and meta-analysis. eClinicalMedicine (Lancet). 2021;38:100997, PMID 34505026

Meta-analysis of 38 RCTs: omega-3 reduced cardiovascular mortality; EPA monotherapy showed stronger cardiovascular protection than EPA+DHA combined.
2.Manson JE et al. Marine n-3 Fatty Acids and Prevention of Cardiovascular Disease and Cancer (VITAL Trial). N Engl J Med. 2019;380(1):23–32, doi:10.1056/NEJMoa1811403

Landmark 25,871-person RCT: 1 g/day omega-3 reduced major cardiovascular events by 28% in those who did not consume fish regularly.
3.Huang Y et al. Omega-3 fatty acids and cognitive function: A meta-analysis and systematic review of RCTs in older adults. Nutrients. 2023;15(3):567, PMID 36637075

Systematic review finding DHA supplementation benefited cognition in mild cognitive impairment; effects strongest in those with low baseline omega-3 intake.
4.Qian F et al. Association Between Omega-3 Fatty Acid Intake and Dyslipidaemia: A Continuous Dose-Response Meta-Analysis of RCTs. J Am Heart Assoc. 2023;12(7):e028479, PMID 37264945

Dose-response meta-analysis confirming linear triglyceride reduction with EPA+DHA; stronger effects at doses above 2 g/day.
5.Bhatt DL et al. Cardiovascular Risk Reduction with Icosapentaenoic Acid for Hypertriglyceridemia (REDUCE-IT). N Engl J Med. 2019;380(1):11–22, doi:10.1056/NEJMoa1812792

Pivotal RCT: 4 g/day pure EPA (icosapentaenoic acid) reduced major cardiovascular events by 25% in high-risk patients on statin therapy.