Myth Buster: Is Your Fish Oil Helping You or Hurting You?
We have all seen the rows of fish oil bottles in the supermarket or glossy “miracle” claims online. The labels look convincing, the promises sound impressive, and it can be hard to tell the real differences.
If you're like me, you are probably not getting enough omega-3 oils in your daily diet. I do not fancy reverting to my Scottish ancestry and eating sardines or kippers for breakfast just to keep up my levels. For most of us, that means looking to supplements, but knowing which one to choose is where it can get tricky.
I want to share what matters when it comes to choosing a fish oil, so you can sidestep the common traps and feel confident you are choosing something that will genuinely support your health.
Myth 1: All omega-3s have the same anti-inflammatory benefits
Fish oil is often thought of as “anti-inflammatory”, but that benefit comes from something very specific: Specialised Pro Resolving Mediators (SPMs). These compounds help your body bring inflammation to a natural close【2,3】.
Here is the thing: not all fish oils have the same SPM levels. In fact, many are never tested for them【4】. Your label might list the omega-3, EPA, or DHA content, but it usually says nothing about how much of the active SPMs you will be getting. And let’s be honest, if a company has gone to the trouble and expense of testing and standardising their SPM levels, they will be shouting about it on the label. If they are not, it is probably not happening.
Not to mention how tricky health product marketing can be, there are plenty of loopholes that allow a label to look impressive without proving that the product delivers on the claims. Without standardised and regulated SPM levels, there is no guarantee you are getting enough to make a meaningful difference【4,5】.
Myth 2: If it is in the capsule, your body will absorb it all
It would be nice if our bodies worked like a sponge, take the capsule, soak up every drop. But omega-3 absorption is a bit trickier than that. The oil needs to be in a form your body can easily use, and it absorbs best when taken with food that contains some healthy fat【6,15】.
Here in Australia, the Therapeutic Goods Administration (TGA) sets quality and safety standards for fish oils that are listed as therapeutic goods. That means oils on the Australian Register of Therapeutic Goods (ARTG) must meet strict guidelines for purity, freshness, and omega-3 content. This is reassuring, but it does not automatically mean the product is optimised for absorption, or that it contains the active compounds (like SPMs) in meaningful amounts.
Some products, especially those sold as general food supplements rather than ARTG-listed therapeutic goods, may use unnecessary fillers, flavourings, or lower-grade oils. While these extras are not necessarily harmful in small amounts, they take up valuable capsule space that could be delivering the nutrients you need.
If the oil is already rancid, poorly stored, or from a questionable source, you might be getting even less benefit. In those cases, you could swallow the same dose as someone else yet end up with far lower omega-3 levels in your blood and tissues【7,8】. Over time, this can result in missing out on the anti-inflammatory, brain, heart, and immune benefits that initially led you to take fish oil【2,3,16,19 】.
Myth 3: If it smells fishy, it is just fish oil being fish oil
Fresh, high-quality fish oil should not smell overly fishy. A strong odour or “repeat” after taking it can be a sign the oil is oxidising (turning rancid). Rancid oils are not only less effective, but they can also actually create oxidative stress in the body, the opposite of what you want from an anti-inflammatory supplement【7,8】.
Processing matters here, too. Poor manufacturing can involve excessive heat, bleaching, or deodorising to mask odours, which may damage delicate fatty acids and strip away beneficial compounds. Choosing a product that is processed gently, stored well, and tested for oxidation helps make sure you are getting the real health benefits, not a damaged oil that works against you【7,9】.
Myth 4: Heavy metals are not an issue anymore
Yes, reputable manufacturers filter out heavy metals like mercury, lead, and arsenic【10】. But this is not universal, especially with some bargain products or those sourced from poorly regulated fisheries. The TGA does have limits for contaminants in ARTG-listed fish oils【11】, but offshore or unlisted supplements might not meet the same standards.
If a brand openly shares its testing results for heavy metals and other contaminants, that is a good sign. If you cannot find that information, you must ask yourself why.
Myth 5: The more omega-3, the better
Well, “Mega Fish Oil” sounds like it should mean mega healthy, right? Sadly, it is not that simple. Your body has a limit to how much omega-3 it can use at one time【1,4,19】. Once you have enough to meet your needs, extra doses do not necessarily give extra benefit.
In fact, very high intakes can thin the blood too much, affect clotting【19】, and may cause digestive upset or interact with some medications【19】. What really matters is quality, freshness, and the presence of active compounds like SPMs, not just a big number on the label. More is not always better, but the right amount of the right oil can make all the difference.
The bigger picture
SPMs are not only important for joint comfort or healthy ageing. They play a role in brain development during pregnancy and breastfeeding, support healthy growth in children, and help protect the brain and nervous system throughout life. In adults, they support cardiovascular health, immune balance, and may help reduce the risk of neurodegeneration【1-4】.
Once you know what to look for, freshness, purity, and those all-important SPM levels, you can feel confident reading a label and knowing whether that oil is truly going to support your health.
Chat to me at your next visit or email for my professional fish oil recommendations (current Wellness for Life clients only).
Disclaimer: This post is for general education only and is not medical advice. Please consult your healthcare professional. See our Medical Disclaimer.
References:
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