Where does Omega-3 come from?

23/05/20234 min read

Fish oil capsules with omega 3 and vitamin D on yellow background.

Did you know that your body can't produce omega 3? If your body can't produce it, where does omega 3 come from? This article answers that very question!

You may already be aware that omega-3s are ‘good’ fats, which are essential to the normal functioning of your body. But did you know that your body does not actually produce omega-3s itself? Why is that? And what exactly is an omega-3? We find out.

What are omegas?

Omega-3s are very important for your body’s heart health, brain function, inflammation processes, and more. There are many types of omega-3s, but the most important ones are ALA, EPA, and DHA.¹ ALA (also known as α-linolenic acid) is mostly found in plants and algae. Your body can convert a small amount of it to EPA (or eicosapentaenoic acid) or DHA (or docosahexaenoic acid) omegas, but the rest is typically used as energy or stored as fat, in the same way as other fats you consume. EPA and DHA are found in seafood, and these are the omega-3s that your body wants to use for your brain, skin, and eyes.²

The human body does not produce omega-3s

For most of the fats that your body needs, it can make from other fats or it can build up from other raw materials. However, with omega-3s, your body cannot make them from scratch and so it must obtain them through your diet and/or through supplements.³ A fat is just a type of chemical compound. To be specific, it is an ester – a compound derived from an acid – of fatty acids. Fatty acids are a carboxylic acid with a long aliphatic chain.⁴ Fats are a key nutrient in the human diet, along with carbohydrates and proteins, and the omega number is a reference to the chemical composition of the fat, where it considers the position of the double bonds relative to the end of the chain of molecules.⁵

How are omega-3s made?

Omega-3s are formed in the chloroplasts of green algae and leaves. Fish also do not produce their own omega-3s. Instead, they get them from seaweed and algae. Grass fed animals such as cattle get their omega-3s from eating grass.⁶ Apart from humanitarian concerns, this is another reason why the diet of animals, which will eventually be consumed as meat, matters.

The best source of omega-3

While seafood tends to be the best source of omega-3s, you can also get them through meat and dairy products. A chicken that has a diet that is high in chia, flax, and canola, for example, will provide meat with a higher omega-3 content. ⁷Kangaroo meat is also a good source of omega-3s, as the animals feed principally on grass.⁸

Food with omega-3

If you do eat seafood, that is often the best method of getting your omega-3s. Fish also contains vitamins such as D and B2, and is rich in calcium, phosphorus, iron, zinc, iodine, magnesium, and potassium.⁹ Oily fish is the best source of omega-3s, so it is worth choosing fish such as anchovies, halibut, herring, mackerel, oysters, salmon, sardines, trout, or tuna.¹⁰ Steaming fish, baking it, or grilling it, are healthy ways to prepare it. Some oily fish contain bones that are very soft and can be eaten, including canned sardines and salmon. It is worth eating the bones, if you are up for it, as the calcium and phosphorus in them help keep your own bones strong. For your diet in general, aim for at least two portions of fish per week, including one of oily fish.¹¹

Fish oil supplements

As an alternative, you could also try taking fish liver oil supplements. In this case, it is important to be aware of how much of the supplement you consume, as fish liver oil also contains vitamin A. Having too much vitamin A over the years may do more harm than good, so you do not want to consume more than 1.5mg in total of the vitamin, daily.¹²If you do not eat fish, there are some products that are sometimes fortified with omega-3s. These include eggs, margarine, milk, juice, soy milk, and yoghurt.¹³

Omega 3 fatty acids foods

You can also find omega-3s in the following foods, though more often than not, they are the less-helpful ALA omega-3s, rather than the preferred EPAs or DHAs: bread, flaxseed, oatmeal, peanut butter, pumpkin seeds, walnuts, Brussels sprouts, kale, spinach, broccoli, cauliflower, canola oil, cod liver oil, and flaxseed oil.¹⁴

Though the ultimate concentration of useful omega-3s is lower in these last foods, they are still very much worth consuming for their extra nutritional benefits in other areas, such as fibres, vitamins, and antioxidants. It is worth keeping in mind that it is often not so much about how much omega-3s you get (beyond a certain minimum), but more about making sure this kind of fat is not outbalanced by omega-6s (i.e. refined vegetable oils), as they compete for the same enzymes.¹⁵