Omega-3 fatty acids are polyunsaturated fatty acids, including plant-based alpha-linolenic acid and the fatty acids EPA and DHA, which are found mainly in oily fish. The body cannot produce them in sufficient amounts itself, so they must be taken in through food.
Good sources of EPA and DHA are oily fish such as salmon, mackerel or herring, while alpha-linolenic acid is found mainly in linseed, rapeseed and walnut oil. The body can convert alpha-linolenic acid into EPA and DHA only to a limited extent, so with low fish consumption there is a greater need for plant sources.
Relevance for nutrition and sport
Omega-3 fatty acids are discussed in connection with cell membrane function and general metabolic processes, among other things. For physically active people, a possible role in recovery after exertion is occasionally cited, although the evidence is mixed overall and does not allow blanket statements.
Anyone who rarely eats fish can top up the requirement with plant oils, nuts and seeds. A balanced overall fatty acid intake is more important than looking at individual fatty acids in isolation. The guide fatty acids tells you more about fats in the diet. One to two portions of oily fish per week are often given in nutrition science as a practical guide.
