Jinfiniti "Total Antioxidant Capacity" -- Worth It?

Jinfiniti calls itself “Jinfiniti Precision Medicine” and refers to its tests as “Precision Tests,” yet offers an extremely low-precision way of assessing antioxidant status with its “Total Antioxidant Capacity (TAC)” test.

I have published research that included measurement of TAC. In that study, we used two different methods to asses it: the ferric-reducing ability of plasma (FRAP) and the oxygen radical absorbance capacity (ORAC) of plasma.

The FRAP assay looks non-specifically at the rate at which plasma reduces the ferric (Fe3+) form of iron to the ferrous (Fe2+) form of iron.

The ORAC assay looks non-specifically at the ability of plasma to prevent the oxidation of fluorescein, a synthetic dye made from phthalic acid, the source of plasticizing phthalates, which was synthesized in the lead-up to the invention of methylene blue, which I described here. The oxidation is initiated with 2,2′-azobis-2-methyl-propanimidamide, a synthetic chemical used to generate free radicals for experiments.

Both of these assays are very non-specific and the complete opposite of “precision.” You could argue that they have some usefulness in summarizing what is happening to antioxidant status. To be honest, though, these were something we measured in our lab because other people did, and they were intended as minor footnotes to our papers that we laughed about behind closed doors because the assays were just so non-specific as to be silly.

According to a Jinfiniti sample report, their TAC assay uses FRAP.

The correlation between ORAC and FRAP is only 0.349, which means the r-squared is 0.12, and the variation in one only explains 12% of the variation in the other.

With a correlation that weak, you have to question whether either assay is “summarizing” anything useful.

The largest contributor to FRAP is uric acid, which accounts for 61.7% of its variation, and a very distant second is ascorbic acid, which accounts for 10.1% of its variation.

The FRAP assay does not count sulfur-based antioxidants at all, which means it leaves out the sulfur groups of albumin — which contribute to 27.8% of the plasma ORAC score — and those of glutathione and cysteine.

The sulfur-based antioxidants are essential to measure as markers of age-related decline in antioxidant defense. These are best calculated as propensities to donate electrons, termed “redox state,” measured in millivolts. The cysteine redox potential declines linearly at a rate of 0.16 mV per year from at least the age of 19. The glutathione redox potential is maintained stably between the ages of 19-45 and then begins declining linearly at a rate of 0.7 mV/year.

Measuring FRAP completely leaves this out. It is not clear what FRAP is summarizing when it only explains 12% of ORAC, and it is definitely clear that it is leaving out central parameters of age-related decline in antioxidant function.

You could measure uric acid and plasma vitamin C, and then you’d have over 70% of your FRAP score, only you would actually know exactly what you were testing.

Your uric acid could go up high enough to cause gout, and your joints would start aching, and your FRAP score would then look amazing.

So, why bother?

This is the absolute opposite of precision.

The oxidative stress section of the Cheat Sheet contains markers of oxidative stress and oxidative damage, as well as all of the nutritional components so that you can explain why oxidative stress might be elevated. It is best to use the comprehensive nutritional screening as currently laid out under “lab tests” in the menu, and use the Cheat Sheet for interpretation.

My Antioxidant course is the best place to learn relevant background information.

One thing that will become clear from that course is that energy metabolism — especially the provision of NADPH and ATP — is the fuel of antioxidant defense. As such, it is better to run the comprehensive screening for energy metabolism, which includes the comprehensive nutritional screening, so that bottlenecks in the provision of ATP and NADPH can be caught.

These tests break down the individual components of antioxidant status and identify the specific things that can be fixed and optimized, the very definition of precision.

“Total Antioxidant Capacity” as measured by FRAP is not precision, not a useful summary, and missing the most important things.

My verdict on the Jinfitini TAC test? Not worth it.