What is TOTOX
TOTOX is a lab number for how oxidised an oil is. Lower means less oxidised.
This guide explains the number. It shows no product's result.
Two lab values
Peroxide value (PV) measures early oxidation: the peroxides that form first when an oil reacts with oxygen.
Source: ISO 3960:2017, peroxide value (opens in a new tab)
Anisidine value (AV, also written p-AV) measures later oxidation: substances called aldehydes, which form as the peroxides break down.
How TOTOX is worked out
TOTOX adds the two values, counting the peroxide value twice:
TOTOX = 2 × PV + AV
Source: GOED Voluntary Monograph, version 9.0 (23 July 2026) (opens in a new tab)
A voluntary limit
GOED's voluntary monograph sets TOTOX at most 26. It's a voluntary industry limit, not a law. SUPPFAX doesn't hold any product to it, and shows no product's TOTOX.
Source: GOED Voluntary Monograph, version 9.0 (23 July 2026) (opens in a new tab)
What a lab result tells you
- It covers one batch, tested at one moment. It says nothing about other batches, or about the same batch later.
- Usually the brand chose the sample, and the lab tested what it was sent.
- SUPPFAX doesn't test products. It shows whether a brand publishes its own results, with a link.
- A result names its batch. Compare that with the batch number on your pack.
Which brands publish it
For each oil, which brands publish lab results that include TOTOX, with a link to each: TOTOX in fish oil and other omega-3 oils: which brands publish it