Maternal exposure to low/no calorie sweeteners does not alter body weight in offspring

ISA statement in response to animal study by Wang et al.

Brussels, 18th January 2022: In response to a new animal study by Wang et al.1, the International Sweeteners Association (ISA) points to the collective evidence which suggests that maternal exposure to low/no calorie sweeteners, during both pregnancy and lactation, does not increase body weight in offspring.  

Looking at the study by Wang et al. in more depth, there are several issues and limitations that need to be considered when interpreting the study results and especially their biological relevance to humans. For example, the study population is an important factor to be considered with regard to the relevance to human health: in fact, differences in gastrointestinal physiology and microbiota composition limit the translation of rodent microbiome research – such as the Wang et al. study – to humans.2

Importantly, also, and in the case of aspartame, the study results cannot be supported by the well understood pathways of aspartame metabolism in the human body. Aspartame is rapidly digested, and its metabolites are absorbed in the small intestine; therefore, neither aspartame nor its metabolites ever reach the colon for direct interaction with the microbiota.3 In addition, due to the rapid breakdown of aspartame, the intact aspartame molecule is not detected in the amniotic fluid or in breastmilk. Accordingly, no mechanism could explain how offspring would be exposed to this sweetener, and hence, experience any of the reported effects. Similarly, research investigating the impact of steviol glycosides on the gut microbiota does not confirm any negative effect.4

Furthermore, the results of this study by Wang et al. are in contrast with the collective body of evidence that was reviewed in a systematic review and meta-analysis of animal studies by Morahan et al.5 This review considered the totality of available animal studies looking into the metabolic and behavioural effects of exposure to low/no calorie sweeteners during pregnancy and lactation. The authors concluded that the balance of evidence suggests maternal exposure to low/no calorie sweeteners in the diet does not increase body weight in offspring.

At a time when obesity and non-communicable diseases including diabetes and dental diseases remain major global health challenges, and in light of current public health recommendations to reduce overall sugar intake, low/no calorie sweeteners can be helpful in creating healthier food environments. They provide a wide choice of sweet-tasting options with low or no calories, and thus can be a useful tool, when used in place of sugar and as part of a balanced diet, in helping reduce overall sugar and calorie intake, as well as in managing blood glucose levels,6 including for pregnant women who may be at risk of gestational diabetes. Low/no calorie sweeteners are also not fermentable by oral bacteria, which means that they do not contribute to tooth demineralisation, which is one of the reasons for tooth decay.6 This can be helpful during pregnancy which often puts a strain on the overall mouth health7,8 and ensuring healthy teeth is all the more important.

  1. Wang et al. A Metagenomics Investigation of Intergenerational Effects of Non-nutritive Sweeteners on Gut Microbiome. Front. Nutr., 14 January 2022.
  2. Hughes RL, Davis CD, Lobach A, Holscher HD. An Overview of Current Knowledge of the Gut Microbiota and Low-Calorie Sweeteners. Nutr Today. 2021 May-Jun;56(3):105-113.
  3. Magnuson BA, Carakostas MC, Moore NH, Poulos SP, Renwick AG. Biological fate of low-calorie sweeteners. Nutr Rev. 2016 Nov;74(11):670-689.
  4. Lobach AR, Roberts A, Rowland IR. Assessing the in vivo data on low/no-calorie sweeteners and the gut microbiota. Food Chem Toxicol. 2019 Feb;124:385-399.
  5. Morahan HL, Leenaars C.H.C, Boakes R.A., Rooney K.B. Metabolic and behavioural effects of prenatal exposure to non-nutritive sweeteners: A systematic review and meta-analysis of rodent models. Physiol Behav. 2019 Oct 21:112696
  6. EFSA Scientific opinion on the substantiation of health claims related to intense sweeteners. EFSA 2011 Journal 9(6): 2229, and 9(4): 2076 and Commission Regulation 432/2012/EU (OJ L 136 25.5.2012, p. 1):
  7. CDC Pregnancy and Oral Health:
  8. NHS Teeth and Gums in Pregnancy: