Aspartame (Q&A): What is it and what foods contain this additive?

Last Updated : 01 December 2021
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    Available for over 30 years, aspartame is approved for use in more than 100 countries around the world. Aspartame is a very thoroughly tested food additive with a comprehensive body of studies conducted in animal models and humans. All of these studies demonstrate that aspartame is safe.

    The first European safety assessments of aspartame were published by the European Commission’s former Scientific Committee on Food (SCF) in 1984. Subsequent complementary assessments were made by the SCF in 1988, 1997 and 2002. Since the establishment of the European Food Safety Authority (EFSA) in 2002, the Authority reconfirmed the safety of aspartame in 2006, 2009, 2010, 2011 and most recently in 2013.

    What is aspartame and why is it used?

    Aspartame is a low calorie sweetener. Aspartame provides 4 Calories per gram (similar to sugar) but because, weight for weight, it is approximately 200 times sweeter than sugar, very little aspartame is needed to sweeten foods. Aspartame therefore adds practically no calories to foods. Aspartame mimics well the taste of sugar, enhances citrus and other fruit flavours, and does not contribute to tooth decay.

    In which products is it used?

    Aspartame is used to replace sugar for the production of ‘energy-reduced’ food or food with ‘no added sugar’. It is also used in the production of food for particular nutritional uses. Examples of foods and beverages falling within these categories include sparkling soft drinks, desserts, sweets, chewing gum, yogurt, and table-top sweeteners.

    What happens to aspartame in the body once it is ingested?

    Aspartame breaks down in the gut into its three constituent parts: two amino acids - aspartic acid and phenylalanine - and methanol, which are then absorbed into the blood. The two amino acids (aspartic acid and phenylalanine) are building blocks of protein and are found naturally in many everyday foods such as meat, fish, cheese, eggs and milk. Methanol is also found naturally in many foods, such as fruits and vegetables and their juices, and is part of the normal diet.

    These components are used in the body in exactly the same ways as when they are derived, in much greater amounts, from common foods and beverage. For example, milk provides about 5 times more phenylalanine and 11 times more aspartic acid than a beverage sweetened with aspartame; tomato juice provides over 3 times the amount of methanol as an aspartame-sweetened beverage. Neither aspartame nor its components can accumulate in the body.

    How can I tell if a product contains aspartame?

    People can identify foods and drinks containing aspartame by looking at the ingredients list on the product label. Like all food additives approved for use in the European Union, aspartame has been assigned an "E-number". Its presence in foods is indicated either by its name (i.e. "aspartame") or by its number (E-951).

    Products containing aspartame should also state that it is a source of phenylalanine. This label is there to help people with a rare inherited genetic disorder called phenylketonuria (PKU). These people cannot metabolise phenylalanine from any source and need to control their intake of this amino acid.

    How was aspartame approved in the European Union?

    Aspartame was first authorised for use by individual Member States in the 1980s. European legislation harmonising the use of low calorie sweeteners in foodstuffs was introduced in 1994, following thorough independent safety evaluations by the European Commission Scientific Committee for Food (SCF) in 1984 and 1988. Further reviews of the data on aspartame were carried out in 1997 and 2002 by the SCF and these reconfirmed its safety.

    Today, the European Food Safety Authority (EFSA) is responsible for the work previously carried out by the SCF. Since the establishment of EFSA in 2002, the Authority reconfirmed the safety of aspartame in 2006, 2009, 2010 and 2011. The latest assessment of aspartame by EFSA was published on 10th December 2013. It forms part of its re-evaluation of all food additives which were authorised in the EU prior to 20 January 2009.

    EFSA concluded that aspartame and its breakdown products in the body (phenylalanine, aspartic acid and methanol) are safe for human consumption at current intake levels and that the current Acceptable Daily Intake (ADI) of 40 milligrams per kilogram of body weight per day is suitable for the general population. However, in patients suffering from the medical condition phenylketonuria (PKU), the above ADI is not applicable, as they require strict adherence to a diet low in phenylalanine. With respect to pregnancy, EFSA noted that there was no risk to the developing foetus from exposure to phenylalanine derived from aspartame at the current ADI (with the exception of women suffering from PKU). EFSA also makes clear that the breakdown products of aspartame are also naturally present in other foods, for example methanol is found in fruit and vegetables. The contribution of breakdown products of aspartame to the overall diet is low.

    Has the safety of aspartame been reviewed by other organisations?

    The full body of science on aspartame has been reviewed by regulatory authorities around the world, including the US Food and Drug Administration (FDA) and the Joint Expert Committee on Food Additives (JECFA) of the United Nations Food & Agriculture Organisation and the World Health Organisation. In every case, aspartame was found to be safe.


    1. European Food Safety Authority (2013). Scientific Opinion on the re-evaluation of aspartame (E 951) as a food additive. EFSA Journal 11(12):3496
    2. Wiebe, N., Padwal, R., Field, C. et al. (2011), a systematic review on the effect of sweeteners on glycemic response and clinically relevant outcomes, BMC Medicine.
    3. Regulation (EC) No 1333/2008 of the European Parliament and of the Council of 16 December 2008 establishing a common authorisation procedure for food additives, food enzymes and food flavourings