Imagine you’ve just bought a bottle of omega-3 supplements. You picked it up because you heard they’re good for your heart, brain, and overall health—and you’re right. The omega-3 fatty acids, especially EPA and DHA, are like nutritional gold for the body. But here’s something most people don’t realize: the real power of your omega-3s depends on how fresh they are.

You could be holding a bottle that looks perfectly fine, but if the oil inside is oxidized—essentially going rancid—it won’t do much good. In fact, it could be doing more harm than help. So how do you know if your omega-3s are fresh? That’s where something called the TOTOX value comes in.

Let’s unpack the science—simply.

What is Oxidation? And Why Does It Matter for Omega-3s?

Oxidation is like rust—but for oils. It happens when omega-3 oils react with oxygen, light, or heat. This reaction breaks down the oil molecules and produces harmful compounds. The process also changes the smell and taste, giving it that nasty "fishy" odour or flavour.

This not only makes the oil unpleasant—it reduces its nutritional value and can even introduce toxic by-products.

The TOTOX Value: A Freshness Score for Omega-3s

The TOTOX value (short for Total Oxidation) is like a freshness score for oils. It combines two measurements to give a full picture of how much an oil has oxidized:

1. Peroxide Value (PV): This measures the early signs of oxidation. Peroxides are the first harmful compounds to form when oil starts breaking down. Even though you can’t smell or taste them, they signal that the oil is no longer fresh.
2. Anisidine Value (AV): This detects the later stages of oxidation—when those invisible peroxides break down into smelly, nasty-tasting substances like aldehydes and ketones. If you’ve ever opened fish oil and it smelled off, that’s AV at work.

To calculate TOTOX:

TOTOX = (2 × PV) + AV

Why double the PV? Because early oxidation products can quickly lead to more damage. TOTOX gives you the full story, not just a snapshot.

How to Interpret the TOTOX Score?

According to global standards:

• PV should be ≤ 5
• AV should be ≤ 20
• TOTOX should be ≤ 26

But for high-quality omega-3 supplements, we want it much lower:

To put this in perspective:

• A 10% oxidized oil = TOTOX ~13.8
• A 25% oxidized oil = TOTOX ~23.1
• A 50% oxidized oil = TOTOX ~47.9 (not good)

Figure 1:  The oxidation of oil over time as measured by peroxide value (PV), anisidine value (AV) and Totox value. Note: PV can decrease over time,so AV and/or Totox calculation is needed to appreciate the whole oxidation story. (Pucci, 2024, CDR Paper 2401)

Why Do Omega-3s Oxidize So Easily?

It comes down to their chemical structure. EPA and DHA have lots of double bonds (EPA has 4, DHA has 5). These make them flexible and beneficial—but also fragile. Think of them as delicate flowers that wilt quickly in harsh conditions.

Also, certain types of carbon atoms in their structure are especially prone to reacting with oxygen. This makes omega-3s more vulnerable than other fats.

What Speeds Up Oxidation?

Several factors can cause omega-3 oils to break down faster:

1. Air (Oxygen): Just like apples turn brown in air, omega-3s degrade when exposed to oxygen.
2. Light: Especially UV light speeds up the breakdown.
3. Heat: High temperatures during processing or storage accelerate oxidation.
4. Time: Even under ideal storage, oxidation slowly happens.
5. Contaminants: Proteins, metals, or impurities can act like matchsticks, sparking the oxidation fire.

Freshness Depends on How the Oil is Made

How the oil is extracted matters a lot. For example:

• Heat-based extraction often results in TOTOX values between 15 and 20.
• Enzymatic extraction at room temperature can keep TOTOX below 10.

This means the production method directly impacts the quality and shelf life of your omega-3 supplement.

How to Choose a Good Omega-3 Supplement?

When you’re shopping for omega-3s, here’s what to look for:

Why This All Matters?

Fresh omega-3 oils deliver:

• Better heart protection
• Sharper brain function
• Reduced inflammation
• Greater effectiveness per dose

But oxidized oils do the opposite—they lose potency, may produce harmful compounds, and taste bad. That’s why checking the TOTOX value is essential.

Final Thoughts: Choose Fresh, Choose Smart

Omega-3 fatty acids are powerful allies for your health. But like fresh fruit, they don’t stay good forever. The TOTOX value is your best tool for judging whether your supplement is still effective—or past its prime.

So the next time you’re buying omega-3s, look beyond the label. Ask about the TOTOX value. Choose supplements made with care and tested for freshness. Your body deserves the best—and that starts with oil that’s still fresh, potent, and pure.

B’spoke Omega 3 Fatty Acids

At B’spoke, we’re passionate about delivering omega-3s that are not just effective—but also exceptionally fresh. That’s why we ensure that the TOTOX values (a mark of high quality and minimal oxidation) of our omega-3 capsules are consistently low.

But we don’t stop there—each bottle is also packed with an oxygen scavenger, a small insert that actively absorbs residual oxygen inside the container. This smart packaging innovation dramatically slows down the oxidation process, keeping the oils fresher for longer, even after opening. For consumers, this means you're not only getting a more potent product from day one, but you also maintain that potency throughout the supplement's shelf life.

References

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