Low/no calorie sweeteners: Safety, emerging research and recommendations

Science news from the 12th EFAD Conference 2019


  • All approved low/no calorie sweeteners have undergone a thorough risk assessment by food safety authorities globally before being approved for use on the market.
  • Low/no calorie sweeteners are used in very small amounts in foods and drinks and current evidence does not support the claim that they have adverse effect on gut microbiota at doses relevant to human use.
  • Calorie and sugar reduction through food reformulation including with the use of low/no calorie sweeteners can have a positive impact on obesity and diabetes.

With obesity and diabetes still on the rise in many parts of the world, there is a growing interest in food reformulation aiming for the development of foods and drinks with lower calories and less sugar, saturated fat and salt. One category of ingredients that can help in reformulating products to achieve sugar reduction is low/no calorie sweeteners (Gibson et al, 2017).

Dietitians and nutritionists around Europe are actively involved in discussions about obesity prevention and/or management, and related nutrition policies including food reformulation; therefore, they are interested in being informed on the latest evidence around the role of low/no calorie sweeteners in this context. In a session about “Low calorie sweeteners in the diet: Safety, emerging research and nutrition recommendations”, supported by the International Sweeteners Association (ISA) in the context of the 12th Conference of the European Federation of the Associations of Dietitians (EFAD), invited renowned experts discussed latest evidence on the safety of low/ no calorie sweeteners, the link between diet and gut microbiota and the recommendations related to sugars’ and low/no calorie sweeteners’ intake.

Safety evaluation of low/no calorie sweeteners by food safety bodies includes a thorough risk assessment

In a talk about the safety of low/no calorie sweeteners, Prof Dominique Parent Massin, from the French Academy of Agriculture (France), explained the approval process for low/no calorie sweeteners and the type of evidence examined by food safety agencies during this procedure.

Food safety agencies around the world have repeatedly assessed the safety of low/no calorie sweeteners and consistently confirm their safety. In Europe, the responsibility of evaluating the safety of all food additives rests with the European Food Safety Authority (EFSA).

The risk assessment process is divided into four steps:

  1. hazard identification,
  2. hazard characterisation,
  3. exposure assessment, and
  4. risk characterisation.

Hazard identification: It involves the detection of a potential hazard, i.e. the potential of a substance to cause harm.

Hazard characterization: The aims of hazard characterization are: 1) to identify the adverse effects induced by a specific substance, 2) to establish a relationship between ingested amount of the substance and manifestation of adverse health effects, and 3) to allocate a Health Based-Guide Value (HBGV). In order to determine HBGV, a large dataset of different studies is assessed including toxicokinetic studies (ADME), sub-chronic and chronic toxicity studies, genotoxicity and carcinogenicity data, reproduction and developmental toxicity studies. The usual HBGV for risk assessment of food additives is the Acceptable Daily Intake (ADI), which is the amount of a substance that can be ingested on a daily basis during a lifetime without adverse health effect.

Exposure assessment: In order to estimate the exposure, the dietary intake of the substance of concern is calculated.

Risk characterization: It consists of comparing exposure (Intake estimates) with the ADI to evaluate the potential health risk on the individual. Exposure data so far have been showing that the ADI for each individual sweetener is not exceeded at maximum permitted level (MPL) in Europe.

Following this thorough process, it has been confirmed that low/no calorie sweeteners are safe for European consumers at maximum permitted level. EFSA is currently conducting a re-evaluation of all low/no-calorie sweeteners approved before 2009 to ensure a continuous assessment of these ingredients’ safety on the basis of the latest available research.

Diet, low/no calorie sweeteners and gut microbiota

Addressing about a topic of high scientific and research interest, Prof Ian Rowland from the University of Reading (UK), reviewed current evidence about the link between gut microbiota composition and obesity, diabetes and metabolic syndrome, concluding that differences in microbiota composition are associated with type 2 diabetes and metabolic syndrome. Further research is needed however to establish whether the associations are causal and to identify the main organisms involved in humans.

In relation to the diet overall, and to low/no calorie sweeteners particularly and gut microbiota, Prof Rowland reminded the audience that low/no calorie sweeteners are used in very small amounts in foods and drinks, and that current evidence does not support the claim that they have any adverse effect on health via impact on gut microbiota at doses relevant to human use (Lobach et al, 2019). Most studies of low/no calorie sweeteners on microbiota are in mice and rats, usually testing very high doses of the substance. Effects in animal studies are small and confounded by inadequate control groups and lack of dietary control. Also, the fact that large differences exists between the gut microbiome profile in laboratory animals and people should be taken into account, so translating data from animal studies that test effects of extremely high doses of low/no calorie sweeteners is questionable. In relation to human studies, these are very small and limited, with important methodological limitations. The effect of overall dietary choices on gut microbiota is prominent, and thus, when conducting human studies on microbiota it is key to control and carefully assess the overall diet.

Recommendations about intake of sugars and low/no calorie sweeteners

In the context of the increasing rates of obesity and diabetes over the last four decades (NCD-RisC, 2017), Dr Margaret Ashwell, OBE, RNutr (UK) talked about recommendations regarding intake of sugars and low/no calorie sweeteners.

With regards to sugars, the World Health Organization’s guideline on free sugars intake for adults and children recommends the reduction of free sugars to less than 10% of daily energy intake across the life course (WHO, 2015). In the UK, the Scientific Advisory Committee on Nutrition (SACN) recommends reduced consumption of free sugars to 5% of dietary energy intake (SACN, 2015).

Furthermore, Dr Ashwell discussed public health nutrition policies aiming to calorie and sugar reduction that can have a positive impact on the epidemics of obesity and diabetes. A recent report by OECD suggests that achieving a 20% reduction in calorie content in energy-dense food via reformulation would have a significant positive effect (OECD, 2019). In the UK, the sugar reduction programme by Public Health England aiming to achieve a 20% sugar reduction across 9 food categories that contribute most to intakes of children up to the age of 18 years started in 2017 and already counts some positive results (PHE, 2019).

One of the strategies to achieve calorie and sugar reduction in food reformulation is the use of low/no calorie sweeteners. Low/no calorie sweeteners can be a helpful tool in reformulation of products as they allow to replace sugar and reduce calories in foods, and especially in beverages, while maintaining the pleasure of sweet taste (Gibson et al, 2017).

In a workshop that took place in November 2018 with the participation of 17 experts, these highlighted that policies relating to sugar reduction and low/no calorie sweeteners’ use differ among different countries (Ashwell et al, paper under publication). Efforts should be made to understand and, where possible, reconcile policy discrepancies by seeking common understanding of the role of low/no calorie sweeteners in the diet by policy makers, scientists and regulatory experts. It would also be helpful to review the regulatory hurdles that impede product development and reformulation designed to reduce sugars and calories.

Reaching consensus about scientific facts related to the role of low/no calorie sweeteners in weight and glucose control, the group of experts concluded that, when used in place of sugars to reduce energy density of foods and drinks, low/no calorie sweeteners can help reduce net energy (calorie) intake and assist weight and diabetes management. Their potential value in the dietary management of obesity and diabetes derives from their role as substitutes for sugars and, hence, calories.

To read the press release for the ISA symposium at the EFAD Conference 2019, please click here.

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