What is Actually Meant By "Not All Fish Oil Is Created Equal" - The 50% Rule Most Brands Hope You Never Learn

Written by Lean Greens Crew | Evidence-Based

Search for “Omega 3” on Amazon and you’ll be hit with a wall of options.

High Strength. Triple Strength. Ultra Pure. 365 Capsules. “Doctor Recommended.”

Some promise a year’s supply for less than the price of a takeaway.

And yet…

If you’ve been swallowing fish oil capsules for months and haven’t noticed:

• Any real difference in joint comfort
• Clearer focus
• Or that general “I feel a bit better for doing this” feeling

You’re not imagining things.

There’s a good chance your fish oil is doing very little.

Not because Omega 3 “doesn’t work”, but because most Omega 3 supplements aren’t actually Omega 3 supplements in any meaningful sense.

They’re something else entirely.

The Great Omega 3 Lie

Here’s the uncomfortable truth.

Fish oil and Omega 3 are not the same thing.

Fish oil is just oil extracted from fish. Omega 3 refers to specific fatty acids within that oil that your body actually uses.

Those fatty acids are:

• EPA (Eicosapentaenoic Acid)
• DHA (Docosahexaenoic Acid)

These are the compounds associated with general wellbeing support, cognitive function, and joint comfort.

Everything else in the capsule?

Mostly filler fat.

And most supplement companies are very happy for you not to notice the difference.

The One Big Thing Most Brands Don’t Want You to Understand

We use this framework a lot because it cuts through the noise.

The Rule of 1.

If something isn’t working, there’s usually one core reason.

With fish oil supplements, the Rule of 1 is this:

Potency matters more than pill size, capsule count, or price.

Most cheap Omega 3 products aren’t weak because they’re badly made.

They’re weak because they’re diluted by design.

Once you understand that, reading a supplement label becomes embarrassingly simple.

Let’s break it down.

Reason #1: The “1000mg Fish Oil” Decoy

This is the oldest trick in the supplement marketing book.

You pick up a bottle. The front label screams:

“1000mg Fish Oil!”

It sounds impressive. It sounds clinical. It sounds like you’re getting a serious dose.

But here’s the reality.

Fish oil is just the carrier

That 1000mg refers to the total oil weight inside the capsule.

It does not tell you how much Omega 3 you’re actually getting.

What you care about are the numbers listed on the back:

• EPA (mg)
• DHA (mg)

In many budget brands, a “1000mg fish oil” capsule contains:

• ~180mg EPA
• ~120mg DHA

That’s 300mg of active Omega 3.

Which means:

• 70% of the capsule is just generic fat
• You’re paying mostly for filler
• And you’d need 3–4 capsules just to hit a meaningful daily intake

Why brands do this

Because “1000mg Fish Oil” looks good on the front of the bottle.

“300mg Omega 3” does not.

So they lean on the bigger, more impressive-sounding number and hope you don’t turn the bottle around.

The fix

Ignore the front label entirely.

Always turn the bottle over and look for:

• EPA (mg)
• DHA (mg)

If those numbers aren’t clearly listed, that’s already a red flag.

Reason #2: The 50% Rule (This Is Where It Gets Embarrassing)

Once you’ve found the EPA and DHA numbers, there’s a dead-simple test you can apply.

We call it The 50% Rule.

Here’s how it works.

1. Add EPA + DHA together
2. Divide that number by the capsule size (usually 1000mg)

That gives you the Omega 3 concentration.

The pass / fail test

• Fail: Less than 500mg EPA/DHA per 1000mg capsule → More than half the capsule is filler oil

• Pass: 500mg or more EPA/DHA → A genuinely concentrated Omega 3 supplement

What most people discover (and wish they hadn’t)

A huge number of popular “Amazon Choice” Omega 3 supplements sit at:

• 25%
• 30%
• Maybe 40% if you’re lucky

Meaning:

• You’re paying for oil your body doesn’t really need
• You’re swallowing extra capsules to compensate
• And the “cheap” price isn’t cheap at all when you do the maths

This isn’t about elitism or “premium” positioning.

It’s about basic arithmetic.

Reason #3: The “Year’s Supply” Trap

This one feels clever. It feels economical. It feels like you’re being responsible.

A massive tub. 365 capsules. Sorted for the year.

Except Omega 3 doesn’t behave like vitamin C.

Omega 3 is fragile

EPA and DHA are polyunsaturated fats.

That means they’re:

• Sensitive to light
• Sensitive to heat
• Sensitive to oxygen

The moment you crack open a giant tub, oxidation begins.

Over time:

• The oil degrades
• The potency drops
• The smell gets worse
• The effectiveness declines

That familiar “fishy burp” people complain about?

That’s often a sign of oxidised oil, not fish oil in general.

Why bulk tubs are a bad idea

If a tub lasts you:

• 6 months
• 9 months
• A full year

There’s a good chance the last capsules are far less effective than the first.

You saved money upfront, but lost quality over time.

The fix

Avoid massive tubs designed to sit open for months.

Look for:

• Smaller batches
• Shorter supply windows
• Products designed to be used within 1–2 months

Freshness matters more than quantity.

Why This Keeps Happening (And Why It’s Not Your Fault)

Most people assume:

• “If it’s sold legally, it must be decent”
• “If lots of people buy it, it must work”
• “Fish oil is fish oil”

Supplement marketing relies heavily on:

• Front-of-pack claims
• Capsule count
• Price anchoring

Very few people are taught how to read the label properly.

Once you are, it’s hard to unsee.

What Actually Matters When Choosing an Omega 3

If you strip everything back, it comes down to three things:

1. EPA + DHA content
2. Concentration (The 50% Rule)
3. Freshness

Everything else is noise.

Brand stories. Buzzwords. Stock photos of salmon leaping upstream.

None of that improves what’s inside the capsule.

Supplements We Suggest (And Why)

This is where we applied the Rule of 1 ourselves.

We looked at the market and asked:

“What is the single biggest failure point in Omega 3 supplements?”

The answer was obvious.

Dilution.

So we designed Good Fats around one principle: Maximum usable Omega 3 per capsule.

No filler theatrics. No misleading front labels.

Just maths that works in your favour.

Good Fats – Premium Omega 3

Good Fats isn’t “fish oil” in the vague, meaningless sense.

It’s a high-concentration Omega 3 delivery system, built to pass the 50% Rule without excuses.

Here’s how it stacks up.

The 75% Standard

Each 1000mg capsule contains:

• 500mg EPA
• 250mg DHA

That’s 750mg of active Omega 3 per capsule.

A 75% concentration, where many popular brands struggle to reach 50%.

What that means in real life

• Fewer capsules per day
• Less filler fat going through your system
• Easier consistency
• Better value when you compare like-for-like

No “fish burps”

Because we use:

• High-purity oil
• Minimal filler
• Fresh, well-handled batches

People don’t get the unpleasant aftertaste they associate with cheaper products.

That’s not luck. That’s quality control.

Freshness over false economy

We don’t sell year-long tubs that slowly degrade in your cupboard.

We sell high-potency monthly supplies, designed to be used while the oil is still at its best.

It’s a deliberate trade-off:

• Slightly less “wow” on capsule count
• Far more confidence in what you’re actually taking

The Bottom Line

If your fish oil hasn’t felt worth it, you’re probably right.

Most Omega 3 supplements fail quietly, diluted by filler and hidden behind big numbers on the front label.

Once you understand:

• EPA
• DHA
• And the 50% Rule

You’ll never look at fish oil the same way again.

Stop paying for capsules full of cheap fat. Start paying for what your body can actually use.

👉 [Shop Good Fats Omega 3 & Check the Label Yourself]