Polyunsaturared fatty acids properties

Benefits of polyunsaturared fatty acids


Polyunsaturated fatty acids are a type of fats that are characterized by the presence of two or more double bonds between the carbon chains that make up the fatty acid.

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Photo of a detail of some cookies composition. The classification of fats can be distinguished according to whether they are saturated, monounsaturated or polyunsaturated.

Some polyunsaturated fatty acids are essential, meaning that the human organism is unable to synthesize them and have to be fed through.

Essential fatty acids are polyunsaturated fats omega 3 (linolenic acid) and omega 6 (linoleic acid).

Essential fatty acids play an important role for the nervous system, cardiovascular health and have a major role in diseases such as arthritis, hyperactivity or lupus.

Types of polyunsaturated fatty acids

The most common polyunsaturated fatty acids in foods are usually those containing 18, 20 and 22 carbons.

The first number indicates the amount of fatty acid carbons. The preceding number designates the number of double bonds or unsaturations it contains. In this case they are polyunsaturated and consequently, the value is greater than one.

Essential fatty acids

Within the group of polyunsaturated fatty acids, there are only two fatty acids that are essential for our body.

These essential fatty acids are linoleic acid (18: 2) and linolenic acid (18: 3), which are called omega 6 and omega 3, respectively.

The structural difference between these two types of omega fatty acids lies in the location of the first double bond they contain in their carbon chain. Being at carbon 6 and at carbon 3, respectively.

Why are they essential fatty acids?

Our body is able to make carbon structures with double bonds from carbon number 9, so, as these two fatty acids contain one and two double bonds (respectively) prior to carbon 9, our body can not synthesize them.

For this reason, they are considered essential and have to be ingested through our food to obtain them, not to generate nutritional deficiencies or synthesis.

All other fatty acids can be synthesized through other substrates in our body, therefore, they are not essential.

Derivatives of essential fatty acids omega 3 and omega 6

Through ingestion of essential fatty acids, our body can synthesize other polyunsaturated fatty acids from longer chains. Among these polyunsaturated fatty acids of longer chains, the most relevant are:

  • C20: 4, arachidonic acid (AA)
  • C20: 5, eicosapentaenoic acid (EPA)
  • C 22: 6, docosahexaenoic acid (DHA)

Bluefish directly contains EPA and DHA fatty acids, and cod liver oil supplements are very effective when the benefits of omega 3 are desired. By directly providing EPA and DHA, they save the body from having to make this transformation.

Types and sources of omega 3

Summary sheet with the different types of omega 3, functions in the body and its sources in the diet, Produced by © Botanical-online

Table of common polyunsaturated fatty acids

Polyunsaturated Fatty AcidNameVegetal food containing itAnimal feed containing it
C18:2Linoleic acid


Most of vegetal oils



Sunflower oil, corn oil, soybean oil and canola oil or rapeseed oil, walnut oil, flax,… Nuts


Borage oil and evening primrose oil
C20:3Dihomo-γ-linolenic acid


Fish oils
C20:4Arachidonic acid


Pork fat, poultry fat
C20:5Eicosapentaenoic acid


Fish oils
C22:5Clupanodonic acidSome types of algae and fish oils
C22:6Docosahexaenoic acid


Fish oils

Foods rich in polyunsaturated fatty acids

Table of foods rich in polyunsaturated fatty acids

Per 100g.Polyunsaturated fatty acids
Linoleic acid

Omega 6



Omega 3


Sunflower oil63,20,1
Soybean oil51,57,3
Sunflower seeds37,40,08
Olive oil9,10,85
Peanut oil320
Palm oil10,10,3
Corn oil50,40,9
Coconut oil1,80
Dried grated coconut1,50
Corn margarine31,30,65
Tunna in vegetal oil5,30,13
Cod liver oil2,61,10
Hard cheese0,440,25
Fresh cheese0,430,46

* Related information:

Low-fat diets

Types of fats

Low fat foods

High fat foods

punto rojo More information on fats.

Written by Editorial Botanical-online team in charge of content writing

27 May, 2023

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