Artificial Sweeteners Explained: Aspartame, Sucralose & Acesulfame K

Sweeteners are substances used to give food and drinks a sweet taste without relying entirely on ordinary sugar. Many are far sweeter than sugar, so manufacturers only need relatively small amounts. Three you will commonly encounter are acesulfame K (E950), aspartame (E951) and sucralose (E955).

They are often called artificial sweeteners, although the broader term non-sugar sweeteners also includes sweeteners from other sources, such as steviol glycosides. They are not simply different names for sugar. Each has its own properties, permitted uses and safety assessment.

Aspartame is probably the best-known artificial sweetener. It is around 200 times sweeter than sugar, so very little is required. On a label it appears as "Sweetener: aspartame" or "Sweetener: E951".

Products containing it carry an additional labelling requirement: the label must indicate that the product contains a source of phenylalanine. This matters for people with phenylketonuria (PKU), a rare inherited condition in which phenylalanine needs to be carefully controlled.

For everyone else, the European safety assessment uses an Acceptable Daily Intake of 40 mg per kg of body weight per day. That level was reconfirmed by EFSA in September 2026 while evaluating the aspartame-acesulfame salt, E962.

Aspartame has attracted more headlines than any other sweetener. Two questions often get mixed together: can something potentially cause harm under some circumstances, and what level of exposure presents a meaningful risk in normal use? Health authorities assess both hazard and actual exposure when setting safety guidance.

That is why a headline about a substance being studied for a possible effect does not automatically mean ordinary dietary exposure has been declared unsafe. The useful approach is neither to ignore research nor to panic over individual headlines, but to look at:

• What the study actually found
• The amount involved
• Whether the evidence came from humans, animals or laboratory research
• How that exposure compares with normal consumption
• What regulatory assessments currently conclude

It depends what you are asking. Comparing two otherwise similar drinks, replacing sugar with an intense sweetener can dramatically reduce the sugar and calorie content. That is a real difference.

But less sugar does not automatically mean more nutritious. A zero-sugar fizzy drink can still provide almost no fibre, protein, vitamins or minerals. A protein bar might contain little sugar but still be a heavily formulated product.

A better question: what does replacing the sugar change about this particular product?

Regulators assessing a sweetener's safety answer a different question from health organisations asking whether non-sugar sweeteners are a good long-term strategy for weight control.

In 2023, the World Health Organization recommended that non-sugar sweeteners should not be relied upon to control body weight or reduce the risk of non-communicable diseases over the long term. WHO classified that recommendation as conditional and noted it does not replace toxicological safety assessments or established acceptable intakes for individual sweeteners.

Not every non-sugar sweetener is described as artificial. Steviol glycosides are sweet compounds derived from the leaves of the Stevia rebaudiana plant, identified in the EU within the E960 group. You will increasingly see them in drinks, yoghurts, protein products, snacks and tabletop sweeteners.

The same rule applies. "Natural" does not automatically make a sweetener nutritionally better, and "artificial" does not automatically mean dangerous. Those words can distract from the more useful questions about dose, evidence, nutrition and the overall product.

Natural vs artificial is not a health score.

Take a protein shake or bar. The brand wants it to show 20 g protein while also advertising low sugar. But protein ingredients do not necessarily taste like a chocolate brownie, caramel biscuit or vanilla milkshake, so manufacturers often use sweeteners and flavourings to create that taste without large quantities of sugar.

That does not automatically make the product bad. It explains why high protein plus low sugar often comes with a longer ingredient list. The front of the pack tells you the marketing benefit. The back tells you how they achieved it.

Foods containing an authorised sweetener generally need the words with sweetener(s) near the name of the food. If a product contains both added sugar and sweeteners, you will generally see with sugar(s) and sweetener(s).

Then check the ingredients for "Sweetener:" followed by E950 or acesulfame K, E951 or aspartame, E955 or sucralose. You do not need to memorise every number. You just need to know where to look.