What’s Fishy about Fish Oils?

Published in
3 min readApr 24, 2018


Of all the nutritional supplements that have caught on in the American market, perhaps none is more abundant than fish oil. In fact, American consumers spend over $1 billion annually on over-the-counter fish oil supplements, motivated by the promise of improved heart health and brain function. But are they really getting what they’re paying for?

The simple answer is: probably not.

Fish oils are a popular source of omega-3s, or “healthy fat.” They are an important fatty acid group that can’t be produced by the body; instead, we must get them from our diets. Depending on the molecular type, some omega-3s can be found in walnuts and flax seeds; but the most popular and well known source is fatty fish, such as wild caught salmon or sardines. Omega-3s are important agents in brain function and controlling inflammation, while deficiencies have been linked to an increased risk for cardiovascular disease and arthritis.

For these reasons, fish oil has become a popular dietary supplement, marketed as an easy way to boost heart health and sharpen mental agility. Food companies have been quick to cash in, adding it to products including cereal, juice, and even milk.

But as with many other vitamins, minerals, and complex molecules, the way that fish oil is extracted and packaged is essential to its holding nutritional value once ingested. This is where most fish oils on the market fall short.

Diagnosing the problem is complicated. First, our bodies absorb naturally sourced omega-3s in different ways, involving different digestive and biochemical processes. Second, the process of extracting pure fish oil is exactly that: a process. Unlike squeezing the juice from an orange, acquiring oil from fish involves separating the omega-3s — namely, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) — from other proteins, fats, and heavy metals (like mercury). Filtering out these substances is technically difficult, time-consuming, and expensive. Most American companies extract fish oil under high heat, up to 500 degrees Fahrenheit which oxidizes the fish oil and produces toxic aldehydes.

Oxidation Affects Quality

In order to bring fish oils to market with greater purity and integrity, BodyBio has developed a more sophisticated, non-oxidized refinement process using freeze dried material and high pressure equipment.

Though more expensive to produce upfront, this method called supercritical fluid extraction, eliminates the damage caused by heat extraction. It also DHA and EPA into smaller molecules to increase the concentration of each capsule. As a result, BodyBio’s Kirunal product offers pure, unoxidized oil nearly three times the amount of DHA and EPA compared to most fish oils on the market, which contain 30% or less.

It is worth noting that while omega-3s are an important part of our diets and cellular health, studies are mixed as to whether fish oil supplements work to actively prevent or lower risk factors for heart disease. There is also evidence to suggest that introducing a surplus of omega-3s is into the diet — whether from foods or supplements — is in fact detrimental. Essential fatty acids, mega-6 and omega-3 need to be balanced. If you feel that your diet may be omega-3 deficient, seek advice from a medical professional or dietician on whether a fish oil product could improve your health and wellness.


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