Do Low-Calorie Sweeteners Help With Weight Loss?

Low- and no-calorie sweeteners, such as acesulfame-K, aspartame, sucralose, saccharin, stevia, and monk fruit, are ingredients that provide a sweet taste with few or no calories – compared to sugar, which provides 4 calories per gram. They are commonly used to reduce sugar in products or as tabletop sweeteners. Because they are much sweeter than sugar, only small amounts are typically needed. Low- and no-calorie sweeteners can be used to support weight loss and weight management when used as part of a balanced diet and healthy lifestyle.  Their potential benefit for weight loss depends largely on what they replace in the diet. 

Randomized controlled trials (RCTs) have shown that replacing sugar with low- and no-calorie sweeteners can reduce added sugar and calorie intake, which may contribute to modest weight loss over time. Conversely, when low- and no-calorie sweeteners are compared to water intake, RCTs indicated no effect on weight outcomes. 

Results of observational – or epidemiological – studies on low- and no-calorie sweeteners have been less consistent. This discrepancy in research findings has led to ongoing debate and differing recommendations on the use of low- and no-calorie sweeteners for weight loss and weight management. While RCTs are the gold standard for evaluating the cause-and-effect relationships between nutrition or food intake and health outcomes, observational studies only identify associations and are best used to help identify potential relationships and areas for further research.    

A recent review highlighted several factors that may help explain inconsistent findings from observational research. Some studies reporting an association between low- and no-calorie sweeteners and higher obesity risk did not adequately account for other factors that influence body weight, changes in diet over time, or what the sweeteners replaced in the diet.  For example, these studies often rely on a single assessment of low- and no-calorie sweetener intake, not dietary patterns over time. Conversely, epidemiological studies that account for calorie and dietary changes have reported findings more consistent with RCTs, showing that replacing sugars with low- and no-calorie sweeteners is associated with lower body weight and reduced obesity risk. 

Further, another important consideration when evaluating research on low- and no-calorie sweeteners and measures of body weight is the potential for “reverse causality” – or the long-standing chicken-and-egg debate. Individuals who are trying to lose weight or manage their weight may have overweight or obesity and use low- or no-calorie sweeteners as a tool. As a result, an observational study could find an association between sweetener use and higher body weight when, in fact, concerns about body weight may have contributed to their use in the first place. For these reasons, associations between the intake of low- and no-calorie sweeteners and obesity should be interpreted cautiously and within the context of the broader body of evidence. 

Overall, it’s important to recognize that low- and no-calorie sweeteners are not a “magic bullet” and do not cause weight loss on their own. However, when used in place of added sugars, they can help reduce calorie intake. This may make it easier for some people to stick with a healthy eating pattern by satisfying a preference for sweetness while limiting calories. 

Several leading health organizations have issued guidance on the use of low- and no-calorie sweeteners for weight management. Just as findings vary across different types of research, organizations differ in how they evaluate the evidence and the recommendations they make.  

The World Health Organization (WHO), the Korean Society of Obesity, the British Dietetic Association, and the Dietary Guidelines for Americans emphasize that water and unsweetened beverages should be the preferred alternatives to sugar-sweetened beverages. Many of these groups recognize that low- and no-calorie sweeteners can help reduce added sugar intake when used in place of sugar-sweetened products, and they all recommend improving overall diet quality and reducing intake of added sugars for weight management. Diabetes-focused organizations, including the American Diabetes Association, Diabetes Canada, and Diabetes Australia, and the American Heart Association similarly recognize a role for low-and no-calorie sweeteners when their use helps reduce sugar, calorie, or carbohydrate intake. 

Recommendations also differ depending on how organizations evaluate and weigh the available evidence. For example, based on observational studies that showed a positive association with obesity outcomes and a lack of long-term evidence from RCTs, the World Health Organization (WHO) issued a guideline including a conditional, or “weak” recommendation that “non-sugar sweeteners not be used as a means of achieving weight control or reducing the risk of noncommunicable diseases.”  Notably, the WHO guideline does not apply to people who have already been diagnosed with diabetes. In contrast, in 2025 the UK Scientific Advisory Committee on Nutrition (SACN) placed greater emphasis on evidence from RCTs showing that replacing free sugars with low- and no-calorie sweeteners reduces calorie intake.  SACN concluded that using these sweeteners in place of free sugars may help with weight management, at least in the short term. 

No, the 2023 WHO recommendation on low- and no-calorie sweeteners does not mean that these are unsafe. Ingredient safety is evaluated using a different type of research than that on health outcomes. This research – known as toxicology –  is conducted to ensure safe food ingredients, and to determine the safe amounts of ingredients for humans. 

The Joint FAO/WHO Expert Committee on Food Additives (JECFA) – an international scientific expert body whose evaluations inform food standards and regulatory decisions worldwide – has established Acceptable Daily Intake (ADI) levels of low- and no-calorie sweeteners based on a systematic review of the toxicology studies to date. These levels are specific to the individual low- and no-calorie sweetener based on the data for each one. 

In the United States, low- and no-calorie sweeteners are deemed safe through either a food additive petition or the GRAS (Generally Recognized as Safe) process. As part of these processes, Food and Drug Administration (FDA) scientists review the research and determine the safety and appropriate use of low- and no-calorie sweeteners for individual food categories and at specified levels of use. Based on the current research available, the FDA has approved the use of several low- and no-calorie sweeteners, including aspartame, acesulfame potassium (Ace-K), Sucralose, Neotame, Advantame, Saccharin, stevia, monk fruit, and thaumatin. 

Yes, randomized controlled trials consistently show that when low- and no-calorie sweeteners replace traditional sugar, they reduce added sugar and calories in the diet, which supports weight loss and weight management. However, when low- and no-calorie sweetener consumption is compared to water intake, randomized controlled trials show no difference in body weight outcomes. 

Research does not support the assertion that use of low- and no-calorie sweeteners increases appetite or preference for sweetness or promotes greater food and calorie intake. Instead, low- and no-calorie sweeteners may help satisfy a desire for sweet taste with little to no calories. Several reviews have also shown that dietary sweetness exposure, or exposure to sweet flavors, from both low- and no-calorie sweeteners or sugars, does not significantly alter sweet taste preferences, food selection, or total calorie intake over time. 

The totality of the evidence suggests that low- and no-calorie sweeteners can be a useful tool for reducing added sugars and calories, particularly when they replace foods and beverages containing added sugars. Randomized controlled trials show that this type of substitution can support modest weight loss and weight management. However, what low- and no-calorie sweeteners replace matters: consuming them in place of added sugars may provide benefits that would not be expected when they replace water or other unsweetened options. Rather than viewing low- and no-calorie sweeteners as a solution on their own, they can be considered one option within an overall healthy dietary pattern.   

1. Laviada‐Molina H, Molina‐Segui F, Pérez‐Gaxiola G, et al. Effects of nonnutritive sweeteners on body weight and BMI in diverse clinical contexts: Systematic review and meta‐analysis. Obesity Reviews. 2020;21(7):e13020. doi:10.1111/obr.13020 

2. Rogers PJ, Appleton KM. The effects of low-calorie sweeteners on energy intake and body weight: a systematic review and meta-analyses of sustained intervention studies. Int J Obes. 2021;45(3):464-478. doi:10.1038/s41366-020-00704-2 

3. World Health Organization, Rios-Leyvraz, Magali, Montez, Jason. Health Effects of the Use of Non-Sugar Sweeteners: A Systematic Review and Meta-Analysis. World Health Organization; 2022. Accessed September 22, 2026. https://iris.who.int/handle/10665/353064 

4. McGlynn ND, Khan TA, Wang L, et al. Association of Low- and No-Calorie Sweetened Beverages as a Replacement for Sugar-Sweetened Beverages With Body Weight and Cardiometabolic Risk: A Systematic Review and Meta-analysis. JAMA Netw Open. 2022;5(3):e222092. doi:10.1001/jamanetworkopen.2022.2092 

5. Espinosa A, Mendoza K, Laviada-Molina H, et al. Effects of Nonnutritive Sweeteners on the BMI of Children and Adolescents: A Systematic Review and Meta-Analysis of Randomized Controlled Trials and Prospective Cohort Studies. Advances in Nutrition. 2024;15(12):100292. doi:10.1016/j.advnut.2024.100292 

6. Shahinfar H, Payandeh N, Zeraattalab-Motlagh S, et al. Comparative effects of different beverages on weight loss in adults: a systematic review and network meta-analysis of randomized trials. Int J Obes. 2025;49(4):578-585. doi:10.1038/s41366-024-01673-6 

7. Wen J, Wu Q, Li S, Liu Y, Wen D. Effects of Non-Nutritive Sweeteners on Weight Loss and Maintenance, Metabolic Improvement, and Appetite Regulation in Weight Management Programs: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrition Reviews. 2026;84(2):318-332. doi:10.1093/nutrit/nuaf094 

8. Li D, Han L, Yu Z, Teng X, Ma Y, Wang D. Effects of non-nutritive sweeteners on body weight: a systematic review and meta-analysis of randomized controlled trial (RCT) studies. J Endocrinol Invest. 2025;49(1):11-24. doi:10.1007/s40618-025-02654-w 

9. Ayoub-Charette S, Nguyen M, Chiavaroli L, et al. Low- and no-calorie sweeteners and health: unravelling the evidence and controversy. Appl Physiol Nutr Metab. 2026;51:1-11. doi:10.1139/apnm-2025-0440 

10. Ayoub-Charette S, Kavanagh ME, Khan TA, Sievenpiper JL. Reconciling conflicting evidence on low- and no-calorie sweeteners and cardiometabolic outcomes: an umbrella review using naïve and bias-adjusted methods. Appl Physiol Nutr Metab. 2025;50:1-26. doi:10.1139/apnm-2025-0068 

11. Higgins KA, Rawal R, Kramer M, Baer DJ, Yerke A, Klurfeld DM. An Overview of Reviews on the Association of Low Calorie Sweetener Consumption With Body Weight and Adiposity. Advances in Nutrition. 2024;15(12):100239. doi:10.1016/j.advnut.2024.100239 

12. 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. doi:10.2337/dc21-2130 

13. Pang MD, Kjølbæk L, Bastings JJAJ, et al. Effect of sweeteners and sweetness enhancers on weight management and gut microbiota composition in individuals with overweight or obesity: the SWEET study. Nat Metab. 2025;7(10):2083-2098. doi:10.1038/s42255-025-01381-z 

14. World Health Organization. Use of Non-Sugar Sweeteners: WHO Guideline. 2023. Accessed September 22, 2026. https://iris.who.int/handle/10665/367660 

15. Choi JH, Song S, Kim SK, et al. Health Effects of Sugar-Sweetened and Artificially Sweetened Beverages: Umbrella Review and Evidence-Based Consensus Statement of the Korean Diabetes Association and the Korean Nutrition Society. Diabetes Metab J. 2026;50(1):32-46. doi:10.4093/dmj.2025.0848 

16. British Dietetic Association, British Nutrition Foundation, Diabetes UK. Joint Position Statement on the Use of Low- or No-Calorie Sweeteners (LNCS). British Dietetic Association; October 2025. Accessed September 22, 2026. https://www.bda.uk.com/static/ff392f8c-3656-4a02-8fee9c040d862c36/Joint-statement-on-the-use-of-low-and-no-calorie-sweeteners-Oct-2025.pdf 

17. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2025-2030. https://cdn.realfood.gov/DGA.pdf 

18. American Diabetes Association Professional Practice Committee for Diabetes*, Bajaj M, McCoy RG, et al. 5. Facilitating Positive Health Behaviors and Well-being to Improve Health Outcomes: Standards of Care in Diabetes—2026. Diabetes Care. 2026;49(Supplement_1):S89-S131. doi:10.2337/dc26-S005 

19. Diabetes Canada. Position Statement: Sugar and Diabetes. Diabetes Canada; January 2020. https://www.diabetes.ca/advocacy-and-policy/our-policy-positions/sugar_and_diabetes 

20. Diabetes Australia. Alternative sweeteners – Can they help manage diabetes? August 5, 2019. Accessed September 22, 2026. https://www.diabetesaustralia.com.au/blog/alternative-sweeteners-diabetes/ 

21. American Heart Association. Low-Calorie Sweeteners. October 10, 2024. Accessed September 22, 2026. https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/sugar/low-calorie-sweeteners 

22. Scientific Advisory Committee on Nutrition. SACN Statement on the WHO Guideline on Non-Sugar Sweeteners: Summary. April 2, 2025. Accessed September 22, 2026. https://www.gov.uk/government/publications/sacn-statement-on-the-who-guideline-on-non-sugar-sweeteners/sacn-statement-on-the-who-guideline-on-non-sugar-sweeteners-summary 

23. World Health Organization. Joint FAO/WHO Expert Committee on Food Additives (JECFA). Accessed September 22, 2026. https://www.who.int/groups/joint-fao-who-expert-committee-on-food-additives-(jecfa) 

24. World Health Organization. JECFA database. June 2026. Accessed September 22, 2026. https://apps.who.int/food-additives-contaminants-jecfa-database/ 

25. US Food and Drug Administration. Food Additives & Petitions. October 10, 2024. Accessed September 22, 2026. https://www.fda.gov/food/food-ingredients-packaging/food-additives-petitions 

26. US Food and Drug Administration. About the GRAS Notification Program. January 4, 2018. Accessed September 22, 2026. https://www.fda.gov/food/generally-recognized-safe-gras/about-gras-notification-program 

27. US Food and Drug Administration. Aspartame and Other Sweeteners in Food. February 27, 2025. Accessed September 22, 2026. https://www.fda.gov/food/food-additives-petitions/aspartame-and-other-sweeteners-food 

28. Harrold JA, Hill S, Radu C, et al. Non-nutritive sweetened beverages versus water after a 52-week weight management programme: a randomised controlled trial. Int J Obes. 2024;48(1):83-93. doi:10.1038/s41366-023-01393-3 

29. Bellisle F. Low‐ or No‐Energy Sweeteners and Body Weight Management: Dissecting a “Minor” Effect. Obesity Reviews. 2025;26(9):e13937. doi:10.1111/obr.13937 

30. Appleton KM, Tuorila H, Bertenshaw EJ, De Graaf C, Mela DJ. Sweet taste exposure and the subsequent acceptance and preference for sweet taste in the diet: systematic review of the published literature. The American Journal of Clinical Nutrition. 2018;107(3):405-419. doi:10.1093/ajcn/nqx031 

31. Bellisle F. Intense Sweeteners, Appetite for the Sweet Taste, and Relationship to Weight Management. Curr Obes Rep. 2015;4(1):106-110. doi:10.1007/s13679-014-0133-8 

32. Mela DJ, Risso D. Does sweetness exposure drive ‘sweet tooth’? Br J Nutr. 2024;131(11):1934-1944. doi:10.1017/S0007114524000485