Omega-3 and TOTOX: The Quality Guide

Omega-3s are essential fatty acids, meaning that neither dogs nor humans can produce sufficient quantities and must obtain them through their diet. The most important are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). They help regulate inflammation, support joint health, promote cognitive function, contribute to cardiovascular function and play a key role in vision.

Omega-3s occur naturally in oily fish (sardines, mackerel and salmon), shellfish such as the New Zealand green-lipped mussel and certain DHA-rich marine microalgae.

In modern diets, however, levels are often too low, which is why omega-3 supplements have become a go-to solution.

Unfortunately, omega-3s have one weakness: they are extremely sensitive to oxidation. Heat, light or even simple exposure to air can degrade their fragile structure and cause a loss of some of their benefits, or even have harmful effects on the body.

It is therefore essential to check their quality, and this is where a key criterion comes in: the TOTOX index.

When Omega-3s Oxidise: A Fragile Process

Omega-3s belong to the polyunsaturated fatty acid family. Their multiple double bonds make them valuable to the body, but also particularly unstable. As soon as they are exposed to oxygen, light or heat, these bonds begin to break down, marking the start of lipid oxidation.

The process unfolds in three stages:

• Initiation: oxygen attacks the double bonds, creating free radicals.
• Propagation: these radicals trigger a chain reaction, producing peroxides, which are small unstable molecules derived from oxygen.
• Decomposition: the peroxides break down into secondary compounds (aldehydes, ketones), which degrade the quality of the oil.

Omega-3 and Oxidation: Why It's a Problem

Oxidised omega-3 oil is not just oil that smells rancid. Oxidation leads to:

• the loss of beneficial properties (joint support, cell membrane fluidity, anti-inflammatory action),
• the formation of unstable molecules (peroxides, aldehydes, isoprostanes), which have been studied for their harmful effects: they increase oxidative stress, promote inflammation and may contribute to processes of accelerated cellular ageing,
• an unpleasant taste that reduces the palatability of the product for the dog.

In short, instead of providing joint and cellular support, an oxidised oil can become an aggravating factor, intensifying inflammation and having pro-oxidant and pro-inflammatory effects on the body.

The Only Reliable Indicator: The TOTOX Index

The TOTOX index (Total Oxidation) is the gold-standard measure for assessing the freshness of an omega-3-rich oil, combining two complementary parameters:

• PV (Peroxide Value): measures the quantity of peroxides, the first compounds formed during omega-3 oxidation. This is primary oxidation, occurring at the very start of degradation.
• pAV (para-Anisidine Value): evaluates the presence of secondary aldehydes, resulting from the breakdown of already-formed peroxides. This is secondary oxidation, corresponding to a more advanced stage where the oil loses its freshness and develops a rancid taste.

Combining both measurements gives a complete picture of omega-3 stability: TOTOX = (2 × PV) + pAV

The Alarming State of the Market

Several scientific studies confirm that many omega-3 supplements exceed the recommended thresholds:

• New Zealand (Albert, 2016): an analysis of 36 fish oil supplements revealed that 50% exceeded the recommended TOTOX threshold.
• United States (Hands, 2024): a recent study of 72 omega-3 supplements sold between 2014 and 2020 showed wide variation in quality. The results reveal that 68% of flavoured products exceeded the TOTOX limit (≤ 26). The study concluded that added flavourings can mask the rancid taste while worsening oxidation, making supplements less reliable and sometimes misleading for consumers.

How to Prevent Omega-3 Oxidation?

To choose an effective and safe supplement, you should:

• Choose transparent brands that publish their test results (measured TOTOX).
• Avoid clear packaging or air-permeable plastic.
• Refrigerate upon receipt and after opening.
• Check for the presence of natural antioxidants (vitamin E, tocopherols, stable oils).
• Choose gentle extraction processes (such as supercritical CO₂) that limit oxidation from the point of manufacture.

PERNIXOL®: Stable, Tested Omega-3s

In light of these findings on omega-3 oxidation, it is essential to choose a supplement that guarantees freshness, stability, and traceability. This is precisely the promise of PERNIXOL®, a liquid supplement designed to support canine joint comfort, formulated to preserve the integrity of omega-3s to the greatest extent possible and offer dogs a natural solution of consistently high quality.

The stability of PERNIXOL® is built on a comprehensive quality process, from the selection of raw materials to final packaging. New Zealand green-lipped mussel oil and microalgae oils are sourced from rigorously evaluated suppliers according to a strict quality control plan, including traceability criteria, environmental compliance and systematic purity and composition analyses. Before being used in the formulation, each batch of ingredients undergoes TOTOX testing to verify its freshness and stability.

The formula is then stabilised by two natural antioxidants: high-oleic sunflower oil, which is particularly rich in oleic acid (omega-9) and recognised for its high resistance to oxidation and its role as a natural preservative, and vitamin E (tocopherols), which neutralises free radicals and extends the shelf life of the omega-3s.

In the finished product, TOTOX indices are measured by an independent laboratory in accordance with European standards, with exemplary results of 6.7 at manufacture and 7.8 after 6 months, well below the international threshold of 26 set by GOED.

To further limit the risk of oxidation, PERNIXOL® is packaged in violet biophotonic glass bottles, which naturally protect the oils from harmful wavelengths. Its 30 ml format, equivalent to 30 days of use, helps avoid keeping an opened bottle for an extended period, maintaining consistent freshness right up to the last dose.

Production is deliberately carried out in small batches to preserve maximum freshness. Once produced, bottles are immediately refrigerated, and customers are advised to store their product in the fridge before and after opening to maintain optimal omega-3 stability over time.

PERNIXOL®420

dogs over 20kg 420mg EPA+DHA per ml

PERNIXOL®210

dogs 10 to 20kg 210mg EPA+DHA per ml

PERNIXOL®70

dogs under 10kg 70mg EPA+DHA per ml

Conclusion

Omega-3s are essential for joint comfort, but their effectiveness depends directly on their freshness. The only reliable indicator for assessing this quality is the TOTOX index. Many analyses show that half of the products on the market exceed the recommended thresholds, with an even greater risk for flavoured supplements.

With PERNIXOL®, every detail is designed to preserve the effectiveness of the omega-3s:

Scientific References

• Albert BB, Derraik JG, Cameron-Smith D, Hofman PL, Tumanov S, Villas-Boas SG, Garg ML, Cutfield WS. Fish oil supplements in New Zealand are highly oxidised and do not meet label content of n-3 PUFA. Sci Rep. 2015 Jan 21;5:7928. doi: 10.1038/srep07928. Erratum in: Sci Rep. 2016 Nov 07;6:35092. doi: 10.1038/srep35092. PMID: 25604397; PMCID: PMC4300506.
• Hands JM, Anderson ML, Cooperman T, Frame LA. A Multi-Year Rancidity Analysis of 72 Marine and Microalgal Oil Omega-3 Supplements. J Diet Suppl. 2024;21(2):195-206. doi: 10.1080/19390211.2023.2252064. Epub 2023 Sep 15. PMID: 37712532.
• GOED. Best-Practice Guidelines on Oxidation Control. 2017.

This article was written by the R&D team at Laboratoire Sensilia, experts in animal nutrition.