It's Time to Stop Using Fish Oil Supplements

They're plagued by a couple of serious problems.

You should probably stop taking fish oil supplements. Like right now.

I know, I know, you’re probably giving the finger to your screen right now, hoping that my phone’s F-you notifications are turned on.

I get it. I do. After all, I’ve long been pushing fish oil supplements with all the evangelical fervor of one of those Southern Bible-thumping preachers:

“The unbelieving, and the murderers, and the whoremongers, and the sorcerers, and all those who don’t ingest large amounts of omega-3 fatty acids through supplemental fish oil, shall have their part in the lake which burneth with fire and brimstone!”

I’ve droned on in the past how fish oils could reduce heart disease, lower blood pressure, improve triglycerides, possibly prevent cancer, improve athletic performance and enhance fat loss, or at the very least quell the inflammatory beast within you but I’ve recently had a change of heart.

Oh, I was probably right about the positive health effects, but with a caveat. Fish oil probably can do all those good things I mentioned, but you run into problems when you squeeze the oil out of much-abused sardines or anchovies and shove it into a capsule that eventually finds its way into your jejenum.

In other words, it’s fish oil supplements that are the problem and not fish oil itself.

Let’s take a closer look at that journey and you’ll start to see what I’m talking about.

Hel-lo, NeMo!

So, Gordo and his anchovy friends are swimming in the pelagic zone off the coast of Peru when Nemo of Disney fame swims by. The anchovies all excitedly wave hello with their fins. Thus distracted by celebrity, they swim unwittingly – ack! -- into a trawler’s fish net and are scooped up into a boat. From there they’re transported to shore – maybe right away, maybe in a day or two -- where they are rudely fractionated into fish meal and crude fish oil.

The oily bounty provided by Gordo and his friends is then stored in large tanks for an indeterminate amount of time before being shipped on to further refining, most likely in China.

There, the oil undergoes several steps, notably repeated heating at high temperatures. The final step is deodorization to remove NEFA (non-esterified fatty acids, which can cause a slew of undesirable metabolic effects), aldehydes, and ketones which are the byproducts responsible for the well-known fishy taste that’s indicative of oxidation and rancidity, byproducts that occurred from improper storage, refrigeration, and repeated heating.

And that’s how we think it goes. There are no specific, agreed-upon guidelines for the catch, isolation, purification, and manufacture of fish oil. Each manufacturer could bloody well do what he wants to manufacture their fish oil, so things could actually be worse than my truncated description of fish oil refinement described above.

Further, there’s no way for the consumer to determine the source of their fish oil, the age of their fish oil, or the extent of the abuses it underwent (how long it sat in the hot sun) before it was packaged and placed on the shelves of your local Whole Foods Market.

Maybe you’re thinking “Big deal. What does it matter if Gordo and his friends got a little skanky and stanky?”

It IS a big deal. If you regularly ingest oxidized fish oil, it can have undesirable effects, the least of which might be increased cholesterol and the worst of which might be toxicity (e.g., liver damage).

Furthermore, this highly processed, highly abused, highly unregulated fish oil would almost assuredly have none of the health-promoting effects you were taking it for in the first place. Instead of decreasing inflammation, it would likely increase it.

Are There Any Good Brands Out There?

There probably are some fish-oil supplement manufacturers out there that monitor the entire processing chain, starting from the beginning when the fish was caught, maybe even stationing a stern overseer on the bridge to make sure the fish were transported to shore, pronto, under proper refrigeration.

The trouble is, it’s almost impossible to know. Four independent studies conducted since 2012 suggest that the public is consuming oxidized products exceeding voluntary and largely unregulated industry standards. (The Global Organization for EPA and DHA – the two coveted omega-3 fatty acids that make fish oil so desirable – recommends that the peroxide limit be set at 26, which is an arbitrary and unitless measure.)

Labdoor, an independent laboratory that analyses vitamins and minerals for purity and nutritional value, doesn’t paint quite as grim a picture as the aforementioned study, although they did find some horrible stuff.

They determined that only 1 out of 10 fish oil supplements were actually rancid, but nearly half were just under the arbitrary limit described above. Some, however, had 11 times greater levels of rancidity than the recommended limits.

It’s a putrid mess, literally.

But let’s say you found a product you trusted, one that you felt confident was well below the accepted levels of oxidation. Great, but there’s another huge problem with taking supplemental fish oil and it has to do with dosage.

Good for the Heart or Bad for the Heart?

There are some really compelling studies out there, ones that suggest taking supplemental fish oil is good for the heart and cardiovascular system in general.

For instance, there are plenty that suggest improved cholesterol levels. A recent one found that taking fish oil could lower blood pressure. Sure, it requires that you take about 2-3 grams of fish oil a day and the blood pressure reduction was modest – about 2 mmHg for both diastolic and systolic blood pressure -- but it’s better than a stick in the eye… or the aorta.

But here comes the worrisome part: Another study, this one rather large and detailing the findings of several RCTs (Randomized Controlled Trials) found that fish oil increased the risk of atrial fibrillation (AFib), a condition where the heart’s upper chambers (atria) beat out of coordination with the lower chambers (ventricles), possibly resulting in blood clots, strokes, heart failure, and other heart-related complications.

This was surprising because several previous studies revealed that fish oil supplementation reduced the risk of AFib.

What in the wide, wide, world of Charlie the tuna is going on?

There are at least a couple of possibilities. One, it relates to dosage as it seems that people taking less than 1,000 mg/day were less likely to develop AFib and those that took more than 1,000 mg/day had a higher risk of developing AFib.

Secondly, the studies that found fish oil to increase the risk of AFib might have been using supplements that had higher levels of oxidation/rancidity, i.e., the bad oil itself might have caused AFib.

Accordingly, many fish oil studies in general that showed fish oil to have no effect or detrimental effect on health might have used bad fish oil. It certainly makes you wonder.

What the Hell Should You Do?

I recently went cold turkey on fish oil supplements. Instead, I went “natural.” I eat a can of sardines, salmon, or tuna approximately 4 or 5 times a week. I also try to eat fish at dinner at least a couple of times a week.

This way, I generally get a sane dose of fatty acids (more is not always better). And granted, I could still be ingesting some peroxides, but it’s a lot harder to disguise rancidity in canned or presumably fresh fish.

I recommend you follow my lead. However, if you’re convinced your fish oil product is legit, consider sticking to a dosage of less than a 1,000 mg/day, at least until we find out more about the relationship between fish oil and a-fib.

References:

Ji Hye Huh and Sang-Ho Jo, Omega 3 Fatty Acids and Atrial Fibrillation, Korean J of Int Med, 2023 May, v. 38 (3): 282-289.

David Cameron-Smith, et al. Fishing for answers: is oxidation of fish oil supplements a problem? J Nutri Sci, v 4: 2015.