Plant-Based Sources of Omega 3 Fatty Acids

There are a wide range of plant-based foods that are particularly important for vegetarians and vegans to help boost their intake of omega 3 fatty acids. However, these foods generally contain alpha-linolenic acid (ALA), rather than eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), and must be converted by the body into DHA and EPA. This conversion process is the conversion process is limited and slow.


Flaxseed and flaxseed oil are the most widely used sources of plant-based omega 3s, and are 6 times richer in n-3 than fish oil. For example, 15 grams of flaxseed oil provides approximately 8 grams of alpha-linolenic acid (ALA), which is converted in the body to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) at an efficiency of 5-10% and 2-5%, respectively.

When purchasing flaxseeds, it is a good idea to buy whole seeds, rather than pre-ground seeds, as the oil contained in these seeds can turn rancid quickly. However, they must be chopped or crushed prior to ingestion, otherwise the seeds will pass through the body undigested. Flax oil has a short shelf life and must be kept refrigerated in a dark bottle.


The flesh and oil produced from nuts such as walnuts, hazel nuts and pecans contain a good source of omega 3.

  • Walnuts (Juglans regia): 6.3% ALA
  • Pecan nuts (Carya illinoinensis): 0.6% ALA
  • Hazel nuts (Corylus avellana): 0.1% ALA

Algae and Kelp

Although oily fish are the most popular source of DHA and EPA, the fish do not manufacture these fatty acids themselves, but obtain it by ingesting algae and kelp. The marine microalgae Schizochytrium and Crypthecodinium cohnii (red algae) have been found to be rich sources of DHA, and can be commercially produced in bioreactors. This is a useful alternative for vegetarians and vegans, and for others who do not want to include fish in their diet. Oil from brown algae (kelp) is an excellent source of EPA.

Fruit and Vegetables

Certain fruit and vegetables contain decent amounts of omega-3, including broccoli, kiwi fruit, strawberries and purslane.