The Tuna Trap

It’s convenient. It’s a protein win. It’s also a little overdone.

There’s a reason we reach for tuna. It’s easy. It’s lean. It lives in the pantry until we remember we need protein.

It’s also one of the few “health foods” that’s been universally embraced across gym bros, midweek meal preppers, and people who haven’t cooked in weeks.

I’m not here to demonise the tin. But I am here to say: it might be time to check how often you’re cracking one open.

Why Tuna’s So Popular

Let’s start with the good stuff.

Tuna is:

• High in protein

• A source of selenium and vitamin D

• Easy to store and eat

• A reliable base for salads, sandwiches, quick meals, or just fork-straight-from-the-can moments

It’s also affordable compared to many other protein sources, and feels like a win when you're not in the mood to cook.

But here’s where the trap sets in.

How Often Is Too Often?

It’s easy to fall into a rhythm where tuna becomes the default every week. Lunch? Tuna salad. Snack? Tuna and crackers.

It’s shelf-stable, high-protein, and doesn’t ask anything of you.

But tuna isn’t meant to be a daily thing. At least not for most people.

Because tuna sits higher up the food chain, and with that comes higher mercury accumulation. Especially species like albacore (white tuna) and yellowfin, which are commonly used in canned and deli tuna.

Mercury: Why It Matters

Mercury is a heavy metal that builds up in the body over time.

In high amounts, it can impact:

• Brain function

• Nervous system regulation

• Fertility and reproductive health

• Detoxification pathways (especially if methylation is sluggish)

This is especially important for:

• Pregnant and breastfeeding people

• Children

• Anyone with compromised detox pathways (yes, those genes matter)

And while a single tin won’t tip the scales, repeated exposure, several times a week, over months or years, can start to stack up.

Omega-3s: The Comparison

Tuna does contain omega-3s, but not at the same level as salmon or sardines.

And depending on the species, processing, and storage, omega-3 content can vary widely.

Here’s a rough comparison per 100g:

Fish	EPA + DHA Omega-3s	Notes
Salmon	~2,000 mg	High and consistent
Sardines	~1,400 mg	Great small-fish option
Mackerel	~1,000–1,500 mg	Omega-3 rich, lower mercury
Tuna (canned)	~200–500 mg	Varies by type; lower overall

So if you’re eating tuna for the omega-3s, it's far from being a good source. You’re better off rotating in fattier, lower-mercury fish. Or looking towards an omega-3 supplement.

Enter: The SMASH Fish

SMASH is an acronym used in nutrition circles for the lower-mercury, high-omega-3 fish:

Sardines Mackerel Anchovies Salmon Herring

These are smaller, oily fish that are:

• Lower on the food chain (so less mercury)

• Richer in omega-3s

• Often tinned too, so just as convenient

So… How Much Tuna Is Too Much?

There’s no one answer, but most health agencies suggest:

• No more than 2–3 serves of tuna per week for the average adult

• Limit further if pregnant, breastfeeding, or under 12

• Choose light tuna (skipjack) over albacore (white) to reduce mercury load

And if you like the convience of a tin, conciser rotating. Bring in salmon. Try mackerel. Give sardines a go (maybe mashed with avocado).

Not because tuna is bad, but because too much of a good thing can quietly turn into a burden.

The Bottom Line

Tuna is convenient. Reliable. Nutrient-rich.

But it’s not meant to be your only source of protein, or your daily dose of omega-3s.

So keep it. Enjoy it. Just don’t let it be your fallback five days a week.

Your body, your brain, and your mercury levels will thank you.