Buyer’s Guide: Choosing a Fish Oil

Use this handy chart to identify which fish oil might be best for your needs. Click to learn more from our resident naturopathic doctor about why we need fish oil, and how to ensure you’re getting the best quality.

Form What it’s good for
Natural triglyceride oil This form is what you get when you “squeeze” the whole fish and extract the natural oil from it. It’s the closest to eating fish in its natural form, and is highly bioavailable. EPA and DHA concentrations are very low.
Ethyl ester oil Occurs when natural triglyceride oil is concentrated and molecularly distilled to remove impurities. The ester form is still in a semi-natural state because it is the result of a process that naturally occurs in the body. The advantage to this form is that it can offer double or triple the levels of EPA and DHA than the natural triglyceride form.
Synthetic triglyceride oil This form occurs when natural triglycerides are converted to ethyl esters for concentration (see above), but then re-converted into synthetic triglycerides. The original position of the triglyceride’s carbon bonds change and the molecule’s overall structure is altered, which impacts the bioavailability of the oil. The benefits to synthetic triglycerides is high bioavailability and therapeutic concentrations of EPA and DHA.
Component What it’s good for
EPA (Eicosapentaenoic Acid) Ideal for healthy heart, mood, joints and immunity
Maintains a healthy heart and circulatory system
Supports joint comfort and mobility
Promotes healthy immune function
Supports optimal metabolism and body composition
Helps maintain healthy insulin levels along with a healthy diet
Promotes positive mood and wellbeing
DHA (Docosahexaenoic Acid) Ideal for cognition, memory and emotional wellbeing
Supports learning and memory
Supports the brain, eyes and immune system
Supports mood and nervous system health
Essential for proper brain development in infants and children
Recommended by physicians for pregnant and lactating women
Source Details
Anchovy, Sardines, Mackerel Fish oil supplements are predominantly produced from sardines, mackerel and anchovies—species that are currently in abundant supply, fished well below mandated limits and considered ideal for sustainability, given their short reproductive cycles. Fish oil from these sources generally provide a higher concentration of omega-3 than krill oil.
Cod Liver Cod liver oil is extracted from cod livers (rather than the flesh of the fish), and is generally richer in DHA than fish oils (but lower in EPA). Cod liver oil also generally contains some vitamins A and D. There is some concern, however, that the high levels of vitamin A can inhibit the body’s absorption of vitamin D.
Salmon A source of omega-3 fatty acids and astaxanthin, wild salmon oil has a naturally occurring ratio of EPA to DHA. Wild salmon may also be a better environmental choice because the oil is extracted from already harvested salmon, using fish parts that would otherwise be wasted, thereby conserving existing stocks.
Krill Research has shown that the body better utilizes omega-3s from krill oil because they are bound to phospholipids, which is unique among marine species. And krill oil has been shown to increase omega-3 levels in humans faster and more efficiently than other marine sources.