The truth about fish, parasites & omega-3s

11 minutes ago
4 min read

Y’all… we need to talk about fish. 😬🐟

Fish has been marketed as one of the ultimate “health foods” - lean protein, omega-3s, heart healthy, brain healthy, etc.

But there’s a side of the fish story that doesn’t get nearly as much attention:

PARASITES + HEAVY METALS + WHAT’S ACTUALLY IN THAT FISH OIL

Yes, fish can carry parasites

Most people hear “parasites in fish” and immediately think sushi.

But parasites aren’t exclusive to sushi.

Wild-caught fish (both freshwater AND saltwater) can harbor a variety of parasites, including protozoa, tapeworms, roundworms/nematodes and flukes.

Some studies have reported very high rates of nematode infection in certain wild fish populations, with particularly striking findings in salmon.

The BC Centre for Disease Control, for example, has reported that a substantial percentage of wild Pacific salmon can be infected with nematodes. And researchers studying fresh-caught Alaskan salmon have reported finding nematodes in essentially every fish examined in certain samples.

And before you think, “Well, I only buy farmed fish…”

That comes with its own concerns.

Farm-raised fish can also have parasitic infections, while aquaculture practices can introduce additional concerns related to antibiotics, pesticides, environmental contaminants and other residues.

So there isn't necessarily a simple “wild = good, farmed = bad” answer.

“But I don't eat sushi…”

I hear this one all the time.

And yes, properly handling and cooking fish is important. Commercial freezing and adequate cooking can dramatically reduce the risk of many fish-borne parasites.

But here's the part that gets interesting:

You can't necessarily tell that a fish contains parasites just by looking at it.

Visible worms may be removed during processing, but microscopic parasite stages or larvae aren't something you can simply spot with your eyes.

And your regular household freezer isn't necessarily equivalent to the commercial parasite-control freezing procedures used by the seafood industry.

Certain parasites are also more resistant to environmental conditions than people realize.

That's one reason proper seafood handling, sourcing and preparation matter.

And if you're someone who is already focused on digestive health and keeping your body's detoxification pathways supported, it's worth knowing what you're putting into your body.

What about mercury?

Parasites aren't the only concern.

Fish can also be a source of mercury exposure.

A simple rule of thumb is that larger, longer-lived predatory fish tend to accumulate more mercury because of bioaccumulation.

Think of fish higher up the food chain: they eat smaller fish, which have accumulated mercury from their environment, and that exposure can build over time.

This is why fish selection matters.

And then there's fish oil…

Here's where things get REALLY interesting.

Omega-3 fatty acids (particularly EPA and DHA)are important nutrients.But taking a fish oil capsule doesn't automatically mean you're getting a high-quality source of omega-3s.

Many conventional fish oils undergo extensive processing, and oils are particularly vulnerable to oxidation if they aren't properly sourced, manufactured and stored.

Poor-quality or oxidized oil isn't something I'd want to casually add to my daily routine.

And while people often focus on getting MORE omega-3s, I think we also need to talk about the other side of the equation:

What are you doing about your excessive omega-6 intake?

Balance between omega-3 and omega-6 is key. Modern diets can be heavily weighted toward omega-6-rich processed foods and seed oils. Traditional diets are often estimated to have had an omega-6-to-omega-3 ratio around 4:1 or lower, while modern Western diets commonly range from 10:1 to 20:1, depending on the population and diet.

Another important caveot: Not every omega-3 supplement is pure EPA/DHA. Depending on the product, the oil can contain other fatty acids INCLUDING omega-6, so you may not be improving your omega-3-to-omega-6 balance as much as you think.

So rather than simply adding more omega-3 on top of an inflammatory, highly processed diet, a good goal is to move toward a more balanced ratio by reducing excess omega-6 sources while increasing quality omega-3s.So what do I recommend?

I'm not saying “never eat fish again.”

In fact, fish can provide valuable protein and omega-3s.

I'm saying be intentional about your sources.

✔️ Choose smaller, lower-mercury fish more often

✔️ Pay attention to sourcing and handling

✔️ Properly cook and prepare seafood

✔️ Don't assume “wild-caught” automatically means parasite-free

✔️ Minimize heavily processed foods and seed oils

✔️ Opt for krill or algal oil vs fish oil

✔️ Look for reputable third-party testing when choosing supplements

✔️ Detox regularly so new parasite exposures can't get a stronghold

✔️ Support your body's natural detoxification systems with a nutrient-dense diet and healthy lifestyle