Omega-3 EPA and DHA: what they are and where to find them in food
Omega-3s are a group of fatty acids. The three main types people talk about are ALA, EPA and DHA.
The US National Institutes of Health Office of Dietary Supplements (NIH ODS) notes that omega-3s are important parts of the membranes around every cell in the body. This article focuses on food: what each type is and which foods contain it.
The three main types
- EPA stands for eicosapentaenoic acid
- DHA stands for docosahexaenoic acid
- ALA stands for alpha-linolenic acid – an essential fatty acid the body cannot make, so it has to come from food
- NIH ODS says the body converts only very small amounts of ALA into EPA and DHA
Where they are found
- EPA and DHA are found in seafood, especially cold-water fish such as salmon, mackerel and tuna, as well as shellfish
- Other oily fish include sardines, trout and herring
- ALA is found in some plant oils, such as flaxseed, soybean and canola (rapeseed) oils
- ALA is also in chia seeds, walnuts, ground flaxseed, soya beans and tofu
How much fish?
- The NHS recommends at least 2 portions of fish a week, including at least 1 of oily fish
- An NHS portion is about 140 g
- MedlinePlus cites the American Heart Association's advice of at least 2 servings a week of fish rich in omega-3s, each about 100 g
- Steam, bake or grill fish rather than frying it
Good to know
- Women who are planning a pregnancy, pregnant or breastfeeding should have no more than 2 portions of oily fish a week, says the NHS
- Some fish may be high in mercury, such as shark and swordfish – people who are pregnant or trying to conceive, and children, should avoid them
- Eating a variety of fish can reduce exposure to contaminants from any one type
- If you have a seafood allergy or do not eat fish, ask a doctor or dietitian about your food choices
- If you choose a fish oil supplement, side effects are usually mild, such as an unpleasant taste, bad breath, headache, heartburn, nausea or diarrhoea. Use it as the label directs and tell your doctor or pharmacist about any medicines or other health products you use.
Read next: Good fats, bad fats: how much you need and where to get them ›
Read next: Balanced nutrition: how much protein, carbohydrate and fat? ›
Read next: 5 everyday habits: quality protein, nitrate-rich veg, omega-3 and rest ›
This article is general health information, not a diagnosis, and results vary from person to person. If you have a medical condition, are pregnant or take medication, talk to your doctor first before changing your diet. Ask us on LINE.
Image and reference from official material in the MyHerbalife media library: Key components of balanced nutrition (illustration) (added to the library: 13 Jan 2025)
Reference: NHS: Fish and shellfish (viewed 14 Oct 2026) ↗ (opens in a new tab)
Herbalife products are not intended to diagnose, treat, cure or prevent any disease.
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