E955 — Sucralose
E955 (Sucralose), a sweetener, is rated "avoid": worth avoiding. A zero-calorie sweetener made by chlorinating sugar. A 2022 randomized trial found it altered gut bacteria and impaired blood-sugar response in healthy adults, a manufacturing impurity has flagged DNA-damage signals, and EFSA itself declined in 2026 to clear it for baking because it can break down at high heat.
What is Sucralose?
A zero-calorie sweetener made by swapping three chlorine atoms onto a sugar molecule, about 600 times sweeter than sugar and heat-stable enough that it is marketed for cooking. Used in diet drinks, sugar-free baked goods and syrups, yogurts, protein powders, and sold as Splenda.
What does it do to the body?
Most of it passes through your gut unabsorbed. But a 2022 randomized controlled trial in healthy adults, at doses below the daily limit, found sucralose shifted the gut microbiome and measurably impaired glycemic response — one of the few times this has been shown in people rather than mice. Separately, sucralose-6-acetate, present both as a manufacturing impurity and as a gut breakdown product, has shown genotoxic (DNA-breaking) signals in laboratory cell assays; that work is contested and has not been replicated in humans. And under prolonged high heat, as in baking or frying, sucralose can degrade into chlorinated compounds. Regular daily users, and anyone baking with it, carry the most exposure.
What regulators say
EFSA's February 2026 re-evaluation confirmed sucralose is safe at currently authorised uses and kept the acceptable daily intake at 15 mg per kg of body weight per day, with exposure below that in all population groups. Notably, EFSA could NOT confirm safety for the proposed extension into fine bakery wares, citing uncertainty about chlorine transferring to other molecules under prolonged high temperatures — a caution that also applies to home baking and frying. The FDA approves it as GRAS. WHO's 2023 guideline advises against sweeteners for weight control.
Risk rating: Avoid
Known or suspected to cause harm: a substance EFSA or another regulator has flagged, or one restricted in some jurisdictions. Best kept out of a regular diet.
Source: EFSA — re-evaluation of sucralose (E 955), February 2026 ↗