5 omega-3 benefits explained by dietitian: Heart, brain and more

Omega-3 fatty acids may support heart health, reduce inflammation and improve brain function, according to a registered dietitian. Since the body cannot produce enough omega-3s on its own, getting them through food is essential.

1. Supports heart health

Omega-3s may help protect the heart by lowering inflammation, blood pressure and blood lipid levels. They may also improve blood flow, raise HDL ("good") cholesterol and support a healthy heart rhythm.

A 2019 review of 13 studies involving more than 127,000 participants found that EPA and DHA supplements significantly reduced the risk of heart attack, coronary heart disease and deaths linked to heart disease. Higher daily doses of around 1,000 milligrams were associated with greater benefits.

2. May improve brain function

Omega-3s play an important role in brain development and cognitive function. Research suggests supplementation may improve memory and attention in both children and older adults.

A 2023 review reported that nearly half of the studies found positive cognitive effects after omega-3 supplementation, with particularly encouraging results in older adults with mild cognitive impairment.

3. May support mental health

According to the dietitian, omega-3s may help ease symptoms of depression. Supplements containing at least 60% EPA per gram have shown the strongest results in studies.

4. Helps reduce inflammation

EPA and DHA help regulate inflammation by lowering levels of certain inflammatory proteins.

Omega-3 supplements may also help reduce symptoms in people with inflammatory conditions, including rheumatoid arthritis and inflammatory bowel disease (IBD).

5. Supports fetal brain development

Omega-3s play a key role in fetal brain development. Experts recommend that pregnant people get enough omega-3s to support healthy development during pregnancy.

Best food sources of omega-3s

Some of the richest sources include:

• Salmon
• Herring
• Sardines
• Oysters
• Flaxseed and flax oil
• Chia seeds

EPA and DHA are mainly found in seafood, while ALA is found in plant-based foods such as nuts, seeds and certain oils.

Supplements and safety

Omega-3 supplements are available as fish oil, krill oil and plant-based algal oil products. They are best taken with a meal containing fat to improve absorption.

The U.S. Food and Drug Administration recommends limiting combined EPA and DHA intake to no more than 3 grams per day, with no more than 2 grams coming from supplements unless advised by a doctor.

Possible side effects include fishy aftertaste, nausea, heartburn, diarrhoea, stomach cramps and headache. Omega-3 supplements may also interact with blood-thinning medications, so people taking anticoagulants should consult a healthcare provider before using them.