Prof. Carlo La Vecchia, University of Milan, Italy
“Low/no calorie sweeteners and risk of non-communicable diseases (NCDs): Correlation vs. Causation”
The role of low-no-calorie sweeteners (LNCS) on cancer has been widely debated since the 70s. Still, the meta-analyses from the WHO 2022 – Health effects of the use of non-sugar sweeteners found no excess risk of other cancers from LNCS.1
To provide further information on the role of LNCS on the risk of cancer, we performed a meta-analysis using the four studies including information on non-SSB and mortality from all cancer sites combined.2 All estimates were close to unity with no between-study heterogeneity. Our pooled estimate for all cancers was 1.01 (95% CI: 0.96, 1.06), thus indicating no excess risk for the highest level of consumption. The International Agency for Research on Cancer (IARC) classified in June 2023 aspartame as possibly carcinogenic to humans (Group 2B) mainly on the basis of a European cohort study on liver cancer.3 However, a study subsequently published based on the Women’s Health Initiative cohort study found no association between aspartame and liver cancer.4 Thus, we can now exclude a consistent association between LNCS and cancer risk, too.
With reference to cardiovascular diseases and related indicators, the WHO 2022 – Health effects of the use of non-sugar sweeteners indicate systematic different findings from randomized controlled trials (RCT) and observational (mainly cohort) studies.1 Observational studies, in fact, found moderate associations between LNCS and cardiovascular diseases or stroke. This was however not confirmed when substitution analysis was performed.5 Randomized clinical trials (RCT) indicate moderate but consistent favorable effects of LNCS on measures of body weight and consequently indicators of metabolic and cardio-metabolic risk.1 Observational studies are exposed to a series of biases, information, selection, follow-up participation biases, etc., and can hardly prove moderate associations, i.e. relative risks of the order of 1.1 to 1.3. The key issue here however is reverse causation, i.e., overweight and obese subjects tend to use and continue to use more frequently LNCS.
- Rios-Leyvraz M, Montez J. Health effects of the use of non-sugar sweeteners: a systematic review and meta-analysis. World Health Organization (WHO) 2022. https://apps.who.int/iris/handle/10665/353064 License: CC BY-NC-SA 3.0 IGO
- Pavanello S, Moretto A, La Vecchia C, Alicandro G. Non-sugar sweeteners and cancer: Toxicological and epidemiological evidence. Regul Toxicol Pharmacol. 2023;139:105369
- Riboli E, Beland FA, Lachenmeier DW, et al. Carcinogenicity of aspartame, methyleugenol, and isoeugenol. Lancet Oncol. 2023;24(8):848-850
- Zhao L, Zhang X, Coday M, et al. Sugar-Sweetened and Artificially Sweetened Beverages and Risk of Liver Cancer and Chronic Liver Disease Mortality. JAMA. 2023 Aug 8;330(6):537-546.
- Lee JJ, Khan TA, McGlynn N, et al. Relation of Change or Substitution of Low- and No-Calorie Sweetened Beverages With Cardiometabolic Outcomes: A Systematic Review and Meta-analysis of Prospective Cohort Studies. Diabetes Care. 2022;45(8):1917-1930
Prof. Katherine Appleton, Bournemouth University, UK
“Low/no calorie sweeteners as a mean of achieving weight control: A review of evidence”
A role for low/no calorie sweeteners (LNCS) in body weight is currently contested. LNCS provide sweet taste in the absence of energy, and theoretically, any effects of LNCS on body weight may be associated with this sweet taste, with the absence of energy, or with some other aspect of LNCS, such as chemical composition. We recently undertook a systematic review and series of meta-analyses of sustained intervention studies aiming to address these three theoretical mechanisms – Rogers PJ, Appleton KM. Int J Obesity 2021; 45: 464-78. We found effects of LNCS on body weight as a result of the absence of energy, but no effects as a result of the sweet taste and no effects as a result of ingestive or post-ingestive consequences. This talk will provide the details of this review, consider our findings in association with body weight management and in relation to sweet taste, compare our results to those of similar other reviews, and place our findings in the context of current recommendations for the use of LNCS in body weight control.
Lucy Boxall, Bournemouth University, UK
“Dietary recommendations for reducing free sugar intakes: Outcomes of a randomised controlled trial”
Investigations into the use of nutrient, food and substitution advice using LCS to aid reductions in free sugars in those with high intakes has been little reported in literature.
In this parallel-group RCT, 242 adults consuming >5% total energy intakes (TEI) from free sugars (%FS) were randomised to receive nutrient-based (N), nutrient- and food-based (NF), nutrient-, food- and food-substitution-based recommendations (NFS) or no recommendations regarding free sugar intakes. Our primary outcome was %FS and adherence at an endpoint of 12 weeks.
Multiple regression models significantly predicted endpoint %FS (F(7,234)=8.86, p <0.001, R2=0.21. Significant predictors were recommendations received (B=-0.636, p=0.029), baseline %FS (B=0.377, p<0.001) and baseline bodyweight (B=-0.04, p=0.04). Mean %FS reduced in all intervention groups N, NF, NFS by 2.47%, 3.25%, 3.08% respectively, in comparison to no change in the control group (-1.18%). There were no significant differences between intervention groups at endpoint %FS. Further analysis into the use of LCS foods showed no differences within or between groups in the amount (grams) or number (counts) of items consumed. Commentary from qualitative interview analyses will be discussed in terms of practical findings and habitual practices. Our results show that providing participants with N, NF or NFS dietary guidelines reduced %FS at 12 weeks.