Omega-3 on your plate: which foods provide it and how much you really need

Before you think about a supplement, it's worth looking at your plate. Food is still the foundation for meeting your Omega-3 needs, and understanding how much foods actually provide helps you know whether extra support is really needed.

Marine sources: the most efficient

Oily fish is by far the most direct source of EPA and DHA, because it doesn't require any conversion process in the body.

• Mackerel: approximately 4.6 g of EPA+DHA per 100 g — the most concentrated fish.
• Wild salmon: between 2 and 2.6 g of EPA+DHA per 100 g.
• Sardines (fresh or canned): between 1 and 2.5 g of EPA+DHA per 100 g.
• Herring and anchovies: between 1 and 2.5 g of EPA+DHA per 100 g.
• Trout: between 0.8 and 1.5 g of EPA+DHA per 100 g.

How much you actually need to eat

With 2-3 servings of oily fish per week (about 100-150 g per serving), you cover, on average, the daily recommendation of 250-500 mg of EPA+DHA. A single serving of salmon can cover 7 to 15 times that minimum daily dose. Canned sardines are one of the most accessible options: a standard tin provides around 1,500 mg of EPA+DHA.

Plant sources: useful, but with a real limitation

Chia and flax seeds, along with walnuts, are rich in ALA (alpha-linolenic acid), the plant-based form of Omega-3. The problem is that the human body converts this ALA into EPA and DHA to a very limited extent: only about 5-10% converts to EPA, and less than 1% to DHA. This conversion tends to be somewhat more efficient in women than in men, but it remains low either way.

• Chia seeds: 10 g provide approximately 1.7 g of ALA (better if consumed ground).
• Ground flaxseed: 15 g provide approximately 3.4 g of ALA.
• Walnuts: a 20-30 g handful a day is a practical amount and has been consistently associated with better memory and attention.

These amounts cover, in practice, the average recommended ALA intake (around 1.1-1.6 g/day, depending on each person's calorie intake), but they don't replace the direct EPA and DHA provided by oily fish or algae.

For those who don't eat fish: algae oil

Microalgae oil (Schizochytrium sp.) is the only plant-based source that provides EPA and DHA already formed, without relying on the limited conversion of ALA. It's the recommended option for those following a vegan or vegetarian diet who want to ensure adequate levels of these fatty acids, particularly for brain health.

A practical combination for everyday life

• 2-3 servings of oily fish per week, prioritising smaller varieties (sardine, mackerel, anchovy) which concentrate fewer heavy metals.
• Daily, 1-2 tablespoons of chia seeds or ground flaxseed, or a handful of walnuts.
• If fish intake is low or non-existent, consider a verified quality Omega-3 supplement as support, not as a substitute for food.

If you'd like to understand better why this nutrient becomes especially relevant from age 45 onwards, you can also read our article on Omega-3 and menopause.

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