A study came out recently about sucralose-6-acetate, a genotoxicin which is apparently found in sucralose.

I wanted to dive in a little bit more, here are some findings and thoughts.

note: I am not a medical professional, and nothing I say here constitutes any medical advice. It’s my own opinions and theories.

Is sucralose safe #

To answer the most important question first: I think there’s evidence that at minimum, sucralose does not lead to a significant increase in cancer. Several studies exist that show at best a minor increase (~10%) correlated with sucralose.

That said, the following concerns is making me consider removing sucralose from my daily diet:

  • The study mentioned showing it contains a possible genotoxin.
  • The possible correlation between sucralose and increased insulin levels.
  • A possible correlation between sucralose and NAFLD.

The NAFLD one especially gives me pause, as it is a good marker for metabolic health.

Over the past year (2023), I’ve lowered my sucralose intake by 75%, down to roughly one sweetened protein shake a day.

In-vivo vs in-vitro #

It’s worth noting that the study talks about in-vitro experiments: these are done in a petri dish or something similar, and not in a live animal. Therefore there could be other biological processes that make this a non-concern. On the other hand, there could also be processes in an in-vivo environment that make this worse.

What is a a genotoxin? #

At it’s core, a genotoxin is something that is known to break down DNA. Since cancer is caused by mutations in the DNA, genotoxins are highly correlate to cancer.

I found a paper that explains the definition in a little bit more detail, at least defining what genotixicity means in the context of carcinogens. The summary is genotoxic carcinogens directly affect DNA and that is the cause of the carcinogen, while non-genotoxic uses some other mechanism, perhaps indirect like hormonal.

It’s not super clear if there is such a thing as non-carcinogenic genotoxin. The abstract states that there is no such thing as a same threshold with a genotoxin: It’s really just a matter of risk level.

What amount of sucralose is safe? #

Assuming the study holds true, what amount of sucralose is safe?

  • The study says 0.67% of sucralose is sucralose-6-acetate.
  • The European Food and Safety Administration states the limit of genotoxins ingested should be 0.0025 μg/kg bw.

The amount of sucralose relative to a microgram of sucralose-6-acetate is ~150. so 150μg of sucralose per 1μg of sucralose-6-acetate.

So for an 80kb person, the daily limit would be: 80 * 0.0025 = 0.2μg. So * 150 that would be at most 30μg of sucralose-6-acetate.

The US sucralose recommended daily allotment is 5mg/kg bw /d. most drinks contains at least 10mg.

So 10mg of sucralose would be 333 times the amount of genotoxin I should be ingesting.

Effectively, there is no practical amount of sucralose that is safe.

Conclusion #

The study is worth taking seriously: clearly sucralose contains a lot of a genotoxin. However, this doesn’t correlate well with the fact that multiple studies have shown that sucralose does not lead to a meaningful increase in cancer.

Although I won’t be buying any more sucralose products, I think the above means one of three things:

  1. The studies on cancer correlations have the wrong conclusion.
  2. The genotoxic nature of sucralose-6-acetate is somehow ameliorated by some other biological process.
  3. The EFSA limitations are low: as weird as it sounds, it may take a higher concentration of genotoxins to lead to a meaningful increase in cancer.