E952

Cyclamate (Cyclamic Acid & Salts)

Last reviewed: 11 May 2026

Zero-calorie sweetener used in UK table-top blends — banned in the US since 1969.

What it is

E952 covers cyclamic acid and its sodium and calcium salts, discovered accidentally in 1937 and approved in the UK and EU from the late 1960s. Sodium cyclamate is the most common form in food.

• 30–50 times sweeter than sugar — the least sweet of the artificial sweeteners
• Sugar-like taste, no bitter aftertaste at use levels
• Heat-stable
• Almost always blended with saccharin (10:1 cyclamate:saccharin) — the two together taste sweeter than the sum of each alone, and the blend masks saccharin's metallic note

Where you'll see it on a UK label

Cyclamate is far less common than aspartame, acesulfame K or sucralose in UK packaged goods. Where you'll find it:

Table-top sweeteners

• Sweet'N Low (UK formulation pairs cyclamate with saccharin)
• Hermesetas (some variants)
• Supermarket own-brand sweetener tablets

Foods and drinks

• Some reduced-sugar soft drinks (largely displaced by aspartame and sucralose)
• Reduced-sugar desserts and jams (rarely)
• Some products marketed for people with diabetes

Non-food

• Chewable vitamins, some toothpaste and mouthwash

What the science shows

The 1969 US ban — bladder tumours in rats

Late-1960s rat studies fed high doses of a cyclamate-saccharin mix and reported bladder tumours. Under the US Delaney Clause — which at that time required banning any food additive shown to cause cancer in animals at any dose — the FDA prohibited cyclamate in food and drinks in 1969. The ban has been challenged repeatedly; the FDA has rejected each petition. Cyclamate remains banned in US food today.

Post-ban research

Follow-up animal studies, including large primate studies, have not consistently reproduced the bladder tumour finding. Human epidemiology — including bladder-cancer cohorts in countries where cyclamate is approved — has not identified a clear cancer signal. Most regulators outside the US, including EFSA and Health Canada, have concluded the human cancer evidence is not sufficient to support a ban. The US position is precautionary: alternatives exist, so the ban stays.

Cyclohexylamine — the metabolite question

The more substantive ongoing concern: roughly 10–30% of people host gut bacteria that convert cyclamate to cyclohexylamine, which is excreted in urine. In animal studies cyclohexylamine has shown effects including testicular atrophy at high doses. The relevance of those doses to human dietary intake is debated, and you can't tell from the outside whether you're a "converter". This metabolic pathway is one reason the EFSA ADI for cyclamate (7mg/kg) is the lowest of the major sweeteners.

Other findings

• Sodium load: sodium cyclamate contributes a small amount of sodium. Trivial next to dietary sodium for most people; calcium cyclamate is the sodium-free alternative.
• Microbiome: some animal studies report shifts in gut bacterial composition, as with other non-nutritive sweeteners. Human clinical significance is unsettled.

Regulatory status

UK/EU: Approved (E952). ADI 7mg/kg body weight per day (EFSA) — the lowest of the approved sweeteners.

US: Banned in food since 1969. Multiple petitions to lift the ban have been rejected.

Canada: Approved (table-top sweeteners only).

Wider: Approved in 50+ countries, including most of Europe.

Reading a UK label

Look for "cyclamate", "sodium cyclamate", "calcium cyclamate", "cyclamic acid" or E952. The most likely place to encounter it is a table-top sweetener — particularly Sweet'N Low UK or Hermesetas, where cyclamate is paired with saccharin (E954). At the 7mg/kg ADI, a 70kg adult's daily limit is 490mg cyclamate — well above typical table-top sweetener intake (each tablet contains around 5–10mg cyclamate).

Last updated: 11 May 2026