Is aspartame safe? Where it's allowed, what the 2023 reviews said, and what it's in
Where aspartame is allowed
United States
Permitted with conditionsThe FDA says aspartame is safe for the general population when made under good manufacturing practices and used under its approved conditions of use. Its acceptable daily intake (ADI) is 50 mg per kg of body weight per day. The FDA disagrees with IARC's 2023 conclusion, and products must carry a statement that they contain phenylalanine, for people with PKU. [1]
Canada
Permitted with conditionsPermitted since 1981, with maximum levels by food (for example 1,000 ppm in unstandardized beverages as consumed). Foods must state, in bold at the end of the ingredient list, that aspartame contains phenylalanine. After reviewing the 2023 reports, Health Canada said it would take no further action at this time. [2, 3]
European Union
Permitted with conditionsAspartame (E 951) is on the EU list of authorised additives, with maximum levels by food category. EFSA's 2013 re-evaluation kept the ADI at 40 mg per kg of body weight per day. Foods containing it must say 'contains a source of phenylalanine' (or 'contains aspartame (a source of phenylalanine)' if listed only by E number). In September 2026 EFSA published a re-evaluation of the aspartame-acesulfame salt (E 962) that also covered aspartame: it said the existing ADI of 40 mg per kg remains valid and found no safety concern at currently reported uses. [4, 5, 6, 9, 10]
What is aspartame?
Aspartame is a high-intensity artificial sweetener. The FDA lists it as about 200 times sweeter than table sugar, and it is sold under brand names such as Nutrasweet and Equal. Because so little is needed, it adds almost no calories.
After it is swallowed, aspartame is fully broken down in the gut into phenylalanine, aspartic acid and methanol. The 2023 expert committee (JECFA) noted that ordinary foods release these same three substances during digestion, and that no intact aspartame enters the bloodstream.
Why it's used, and where you'll find it
Manufacturers use aspartame to keep a sweet taste while cutting sugar and calories. Health Canada's permitted-sweeteners list allows it in beverages, chewing gum and breath fresheners, breakfast cereals and tabletop sweeteners, and says that in unstandardized bakery products it must be encapsulated to prevent degradation during baking.
What the research and regulators say
What the 2023 'possibly carcinogenic' label means
In June 2023 a working group of 25 experts at IARC, the WHO's cancer research agency, classified aspartame as 'possibly carcinogenic to humans' (Group 2B). It cited limited evidence in humans for hepatocellular carcinoma (a type of liver cancer), plus limited evidence in animals and limited mechanistic evidence. The human evidence came from only three studies of artificially sweetened drinks, and IARC said chance, bias or confounding could not be ruled out. WHO explains that IARC classifications reflect how strong the evidence is that something can cause cancer, not the risk at a given level of exposure. [7, 8]
What the intake-limit review concluded
JECFA, the joint WHO and FAO committee that sets acceptable intakes, reviewed aspartame at the same time. It found no convincing evidence from animal or human data of adverse effects after ingestion and reaffirmed the ADI of 0 to 40 mg per kg of body weight per day. WHO gave an example: with cans containing 200 or 300 mg of aspartame, a 70 kg adult would need more than 9 to 14 cans of diet soft drink a day to exceed it, assuming no other intake from other food sources. WHO also said potential effects that have been described need to be investigated by more and better studies. [7, 8]
How national regulators responded
The FDA said it disagrees with IARC's conclusion that the studies support classifying aspartame as a possible carcinogen, and its ADI remains 50 mg per kg. Health Canada said it will take no further action at this time, and will decide whether action is needed if new scientific information becomes available. EFSA's full re-evaluation, completed in December 2013, concluded aspartame and its breakdown products are safe for the general population, including infants, children and pregnant women. In September 2026 EFSA reported that the available evidence does not support a causal link between current dietary exposure to aspartame and adverse effects such as cancer, and that the ADI of 40 mg per kg remains valid. [1, 2, 4, 9, 10]
Phenylalanine and PKU
The clearest health issue is phenylketonuria (PKU), a rare inherited condition in which the body cannot process phenylalanine. The FDA says people with PKU should avoid or restrict aspartame, which is why labels in the US, Canada and EU carry a phenylalanine statement. [1, 2, 6]
Who might choose to avoid it
People with PKU should avoid or limit aspartame, according to the FDA, and follow their own medical team's advice. Some people also cut back on artificial sweeteners for personal reasons, but none of the regulators reviewed here has told the general population to avoid aspartame.
How to spot it on a label
Look for 'aspartame' or 'E 951' in the ingredient list, usually near the word 'sweetener', plus a phenylalanine statement (in the EU, 'contains a source of phenylalanine'). The aspartame-acesulfame salt (E 962) triggers the same EU wording. Brand names include Nutrasweet, Equal and Sugar Twin.
Check what's in your own productsScan a barcode or a label photo and Label X-Ray flags aspartame and everything else in plain English, with your allergies checked automatically.
Frequently asked questions
Is aspartame banned in Europe?
No. Aspartame (E 951) is on the EU list of authorised additives. EFSA's 2013 re-evaluation set the ADI at 40 mg per kg of body weight per day, and its September 2026 opinion on the aspartame-acesulfame salt said that ADI remains valid.
Is aspartame a carcinogen?
IARC classified it as 'possibly carcinogenic to humans' (Group 2B) in 2023, based on limited evidence. That describes the strength of the evidence, not the level of risk. JECFA found no convincing evidence of harm at current intakes.
Is aspartame banned in Canada?
No. Health Canada has permitted it since 1981 and, after the 2023 IARC and JECFA reports, said it would take no further action at this time.
Is aspartame safe during pregnancy?
EFSA's 2013 re-evaluation concluded that aspartame and its breakdown products are safe for the general population, including pregnant women, within the ADI of 40 mg per kg of body weight per day. EFSA says that ADI does not apply to people with PKU. Your own doctor is the right person for questions about your situation.
Why does the label mention phenylalanine?
Aspartame is broken down in the body into phenylalanine, aspartic acid and methanol. The statement helps people with PKU, who must restrict phenylalanine, avoid it.
Related ingredients
Sources
- U.S. FDA — Aspartame and Other Sweeteners in Food (accessed 2026-09-19)
- Health Canada — Aspartame (accessed 2026-09-19)
- Health Canada — 9. List of Permitted Sweeteners (Lists of Permitted Food Additives) (accessed 2026-09-19)
- EFSA — Aspartame (accessed 2026-09-19)
- EUR-Lex (European Union) — Commission Regulation (EU) No 1129/2011 amending Annex II to Regulation (EC) No 1333/2008 by establishing a Union list of food additives (as adopted; later amended) (accessed 2026-09-19)
- EUR-Lex (European Union) — Regulation (EU) No 1169/2011 on the provision of food information to consumers (Annex III, point 2.3, as adopted) (accessed 2026-09-19)
- IARC / WHO — Summary of findings of the evaluation of aspartame at the IARC Monographs 134th Meeting and JECFA 96th meeting (accessed 2026-09-19)
- WHO — Aspartame hazard and risk assessment results released (accessed 2026-09-19)
- EFSA — EFSA concludes the salt of aspartame-acesulfame (E 962) is safe at current exposure levels (accessed 2026-09-19)
- EFSA — Re-evaluation of salt of aspartame-acesulfame (E 962) as food additive (plain-language summary) (accessed 2026-09-19)
This page summarizes what regulators and published research say, as of the review date above. Rules and evidence change; check the linked sources for the latest. It is general information, not medical advice — talk to a doctor or pharmacist about your own health.