Evidence-based nutrition, in plain English — every entry sourced from clinical research.

Omega-3s are a family of essential polyunsaturated fats the body cannot make in meaningful amounts, so they must come from the plate. The two with the strongest evidence, EPA and DHA, are concentrated in oily fish such as salmon, mackerel, sardines and herring; the plant form, ALA, comes from flaxseed, chia, walnuts and rapeseed oil and is converted only modestly into the active forms. Beyond their well-known role in heart and brain health, omega-3s are prized for calming inflammation and supporting healthy blood fats.

What is Omega-3?

Omega-3 is a polyunsaturated fat that plays a critical role in building cell membranes, supporting brain and eye function, and dampening excess inflammation. While many general diets overlook it, maintaining optimal levels of Omega-3 is frequently tracked by people working to optimize their Triglycerides.

Top Foods High in Omega-3

A data-driven breakdown of the foods with the highest concentration of Omega-3 per 100 g.

Highest dietary sources of Omega-3, per 100 g edible portion
FoodOmega-3
Flaxseed19.42 g
Mackerel2.3 g
Salmon (Atlantic)1.44 g
Sardines0.98 g
Rainbow Trout0.79 g
Extra Virgin Olive Oil0.65 g
Mussels0.44 g
Tuna (canned, light)0.23 g
Cod0.18 g
Cheddar Cheese0.13 g
Scallops0.11 g
Eggs0.09 g

How Omega-3 Impacts Triglycerides

Research links diets rich in Omega-3 to changes in Triglycerides. Diets naturally abundant in this compound often support lower Triglycerides markers by reducing the liver's output of triglyceride-carrying particles and speeding the clearance of fats from the blood.

Encyclopedia Insight: For maximum absorption, pair Omega-3-rich foods with a source of antioxidants such as colourful vegetables, which help protect these delicate fats from oxidation to optimize bioavailability.

Scientific references & clinical evidence

This guide is built on peer-reviewed research — verify the primary sources below.

  1. BMJ (2022). “Vitamin D and marine omega-3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial”. PubMed / source ↗
  2. Cochrane Database of Systematic Reviews (2021). “Omega-3 fatty acids for depression in adults”. PubMed / source ↗
  3. Critical Reviews in Food Science and Nutrition (2022). “Omega-3 supplementation and diabetes: a systematic review and meta-analysis”. PubMed / source ↗
  4. Cochrane Database of Systematic Reviews (2020). “Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease”. PubMed / source ↗

Written by the Nutrition Encyclopedia team · medically reviewed by Dr. Sunaina Tariq, MBBS

Last updated 31 July 2026

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