Lifestyle & Fitness

Does Diet Soda Make You Fat? The Truth You May Not Know 2025

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In today’s health-conscious world, diet soda has become a popular choice for those who are trying to cut calories and lose weight, and even switching to diet soda is considered as the adoption of healthy habits by some. However, there has been an ongoing debate about whether diet soda can actually make you gain weight.

Some studies suggest that diet soda may contribute to weight gain, while others claim it has no impact on weight. So, what is the truth? Does diet soda cause belly fat? Or can quitting soda — even diet soda — help you lose weight?

In this article, we shed light on the lesser-known facts about diet drinks and their effects on weight management. We will also provide tips on reducing cravings for diet soda and suggest healthier weight-loss drinks to consider.

Does Diet Soda Make You Gain Weight?

Scientific research is inconclusive, but moderate diet soda consumption is unlikely to cause weight gain. Some studies suggest that artificial sweeteners in diet soda may trigger cravings and lead to overeating. The relationship between diet soda and weight gain is still a topic of debate. It’s important to focus on a balanced diet, regular physical activity, and overall healthy lifestyle choices for weight management. Consult with a healthcare professional or registered dietitian for personalized advice.

What Is Diet Soda?

Diet soda is a carbonated beverage that is marketed as a low-calorie or calorie-free alternative to regular soda. It is sweetened with artificial sweeteners, such as aspartame, saccharin, cyclamate, or stevia, instead of sugar.

Why Does Diet Soda Make You Gain Weight?

One of the main reasons people drink diet soda is because it contains no-calorie sweeteners instead of sugar, and hence zero calories.

On the other hand, regular soda is loaded with sugar and calories, which can quickly add up and contribute to weight gain. But diet soda contains no calories, making it a seemingly attractive option for those watching their waistline.

However, despite being marketed as a low-calorie or calorie-free alternative to regular soda, there are several reasons why diet soda may contribute to weight gain.

Artificial Sweeteners

No-calorie sweeteners used in diet sodas can trigger sweet taste receptors[1] and hence trigger the release of insulin, a hormone that regulates blood sugar levels — even though there’s no sugar present.

Insulin helps transport sugar from the bloodstream into the cells for energy. When insulin levels are high, it can increase hunger and cravings[2] for sugar and other carbohydrates, leading to overeating and weight gain.

Increased Appetite

Drinking diet soda might disrupt the body’s natural hunger cues. The sweet taste of diet soda can confuse the brain and increase appetite, causing people to eat more than they need. This can result in excess calorie intake, leading to weight gain over time.

However, most studies have demonstrated that sweeteners such as aspartame[3] do not increase sweetness preference or calorie intake.[4] So, diet soda is probably still better for weight management than normal soda simply because of the lower calories.

Metabolism Disruption

Some studies suggest that consuming diet soda is increasingly linked to metabolic disruption,[5] which might lead to weight gain.

Also, research has shown that artificial sweeteners can alter gut bacteria,[6] which play a crucial role in metabolism. An imbalance in gut bacteria may affect the body’s ability to balance blood sugar,[7] leading to weight gain.

However, a recent meta-analysis found no link between diet soda consumption and metabolic issues,[8] and any differences in microbiome balance due to diet soda are likely very minimal.[9] Due to these contradictory results, more research is needed.

Psychological Factors

The perception that diet soda is “calorie-free” or “healthy” can lead to a psychological mindset that justifies indulging in other high-calorie foods or overeating. This may result in an overall increase in calorie intake, leading to weight gain.

Tips To Reduce Cravings For Diet Soda

If you find yourself craving diet sodas frequently and want to reduce your intake, here are some tips that may help:

  1. Drink Water: Often, our body can mistake thirst for hunger or cravings. Drinking water can help keep you hydrated and may reduce cravings for diet soda.
  2. Limit Artificial Sweeteners: If you consume other products containing artificial sweeteners, such as candies or snacks, try limiting your intake. Read food labels carefully and choose natural sweeteners, such as stevia or honey, as alternatives. Try to avoid erythritol, which has recently been associated with thrombosis and adverse cardiac[10] events.
  3. Opt For Healthier Alternatives: Instead of reaching for diet soda, choose healthier alternatives such as herbal tea, infused water, or sparkling water with a slice of lemon or lime for a refreshing drink.
  4. Identify Triggers: Pay attention to situations or emotions that trigger your cravings for diet soda, such as stress or boredom. Finding alternative ways to cope with these triggers, such as practicing mindfulness, exercising, or engaging in a hobby, may help reduce your cravings.
  5. Seek Support: If you find it challenging to reduce your cravings for diet soda, seek support from family, friends, a dietitian, or other healthcare professional.

Healthy Weight Loss Drinks You Should Try

While diet soda may not directly cause weight gain, plenty of other healthier options for weight loss drinks exist.

Here are some recommendations you can try as part of a healthy weight-loss meal:

  1. Water: The most natural and calorie-free drink you can have is water, and it is essential for overall health and can help you stay hydrated, which is crucial for weight loss.
  2. Green Tea: Green tea is known for its antioxidant properties and metabolism-boosting effects. It contains catechins, which are known to help increase fat oxidation[11] — i.e., fat burning — and improve insulin sensitivity, making it a great option for weight loss.
  3. Black Coffee: Black coffee is low in calories and can help boost metabolism and increase fat oxidation. It contains caffeine, which can help reduce appetite,[12] improve physical performance,[13] and increase energy levels during workouts, making it a popular choice for those looking to lose weight.
  4. Infused Water: Infused water is a refreshing and flavorful option that can be easily made at home by adding sliced fruits, vegetables, or herbs to the water.
  5. Sparkling Water: Sparkling water or seltzer water is another calorie-free option that can be a great alternative to soda.

The Takeaway

Whether diet soda makes you fat is still a subject of debate.[14] While some theories suggest that artificial sweeteners may trigger cravings and lead to overeating, scientific research has not found solid evidence to support this claim. However, it’s important to note that diet soda may not necessarily aid in weight loss efforts either.

If you’re trying to lose weight, it’s crucial to focus on a balanced diet, regular physical activity, and overall healthy lifestyle choices. Moderation is key when consuming diet soda or any other beverages, and it’s always best to consult with a registered dietitian for personalized advice.

Remember that achieving and maintaining a healthy weight involves a comprehensive approach, and it’s important to consider various factors beyond just the calorie counting in the consumption of diet soda.

+ 14 Sources

  1. Turner, A., Veysey, M., Keely, S., Scarlett, C.J., Lucock, M. and Beckett, E.L. (2020). Intense Sweeteners, Taste Receptors and the Gut Microbiome: A Metabolic Health Perspective. International Journal of Environmental Research and Public Health, [online] 17(11), pp.4094–4094. doi:https://doi.org/10.3390/ijerph17114094.
  2. Fereshteh Shahcheraghi, Neda Lotfi Yaghin and Mahdavi, R. (2019). Relationship between hedonic hunger and serum levels of insulin, leptin and BDNF in the Iranian population. Physiology & Behavior, [online] 199, pp.84–87. doi:https://doi.org/10.1016/j.physbeh.2018.11.013.
  3. Kirnjot Mehat, Chen, Y. and Corpe, C. (2022). The Combined Effects of Aspartame and Acesulfame-K Blends on Appetite: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Advances in Nutrition, [online] 13(6), pp.2329–2340. doi:https://doi.org/10.1093/advances/nmac072.
  4. Wilk, K., Wiktoria Korytek, Pelczynska, M., Malgorzata Moszak and Pawel Bogdanski (2022). The Effect of Artificial Sweeteners Use on Sweet Taste Perception and Weight Loss Efficacy: A Review. Nutrients, [online] 14(6), pp.1261–1261. doi:https://doi.org/10.3390/nu14061261.
  5. Muli, S., Jantje Goerdten, Kolade Oluwagbemigun, Floegel, A., Schmid, M. and Nöthlings, U. (2021). A Systematic Review of Metabolomic Biomarkers for the Intake of Sugar-Sweetened and Low-Calorie Sweetened Beverages. Metabolites, [online] 11(8), pp.546–546. doi:https://doi.org/10.3390/metabo11080546.
  6. Asnicar, F., Berry, S.D., Valdes, A.M., Nguyen, L.H., Gianmarco Piccinno, Drew, D.A., Leeming, E.R., Gibson, R.J., Le, C.I., Haya Al Khatib, Francis, L., Banach, M., Olatz Mompeo, Mireia Valles-Colomer, Tett, A., Beghini, F., Dubois, L., Bazzani, D., Thomas, A.P. and Mirzayi, C. (2021). Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals. Nature Medicine, [online] 27(2), pp.321–332. doi:https://doi.org/10.1038/s41591-020-01183-8.
  7. Jotham Suez, Tal Korem, Zeevi, D., Gili Zilberman-Schapira, Thaiss, C.A., Maza, O., Israeli, D., Niv Zmora, Gilad, S., Weinberger, A., Kuperman, Y., Alon Harmelin, Kolodkin-Gal, I., Shapiro, H., Halpern, Z., Segal, E. and Eran Elinav (2014). Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature, [online] 514(7521), pp.181–186. doi:https://doi.org/10.1038/nature13793.
  8. Zhang, R., Noronha, J.C., Khan, T., McGlynn, N., Back, S., Grant, S.M., Cyril and Sievenpiper, J.L. (2023). The Effect of Non-Nutritive Sweetened Beverages on Postprandial Glycemic and Endocrine Responses: A Systematic Review and Network Meta-Analysis. Nutrients, [online] 15(4), pp.1050–1050. doi:https://doi.org/10.3390/nu15041050.
  9. Ahmad, S.Y., Friel, J.K. and MacKay, D.S. (2020). The Effects of Non-Nutritive Artificial Sweeteners, Aspartame and Sucralose, on the Gut Microbiome in Healthy Adults: Secondary Outcomes of a Randomized Double-Blinded Crossover Clinical Trial. Nutrients, [online] 12(11), pp.3408–3408. doi:https://doi.org/10.3390/nu12113408.
  10. Witkowski, M., Nemet, I., Alamri, H., Wilcox, J., Gupta, N., Nimer, N., Arash Haghikia, Li, X.S., Wu, Y., Prasenjit Prasad Saha, Demuth, I., Maximilian König, Steinhagen-Thiessen, E., Cajka, T., Fiehn, O., Landmesser, U., W.H. Wilson Tang and Hazen, S.L. (2023). The artificial sweetener erythritol and cardiovascular event risk. Nature Medicine, [online] 29(3), pp.710–718. doi:https://doi.org/10.1038/s41591-023-02223-9.
  11. Mark, Sahin, M. and Cook, M.C. (2018). Matcha Green Tea Drinks Enhance Fat Oxidation During Brisk Walking in Females. International Journal of Sport Nutrition and Exercise Metabolism, [online] 28(5), pp.536–541. doi:https://doi.org/10.1123/ijsnem.2017-0237.
  12. Schubert, M.M., Irwin, C., Seay, R.F., Clarke, H., Allegro, D. and Desbrow, B. (2017). Caffeine, coffee, and appetite control: a review. International Journal of Food Sciences and Nutrition, [online] 68(8), pp.901–912. doi:https://doi.org/10.1080/09637486.2017.1320537.
  13. Guest, N.S., VanDusseldorp, T.A., Nelson, M.L., Grgic, J., Schoenfeld, B.J., Nathaniel D.M. Jenkins, Arent, S.M., Antonio, J., Stout, J.R., Trexler, E.T., Smith-Ryan, A.E., Goldstein, E.R., Kalman, D.S. and Campbell, B. (2021). International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition, [online] 18(1). doi:https://doi.org/10.1186/s12970-020-00383-4.
  14. Pang, M., Goossens, G.H. and Blaak, E.E. (2021). The Impact of Artificial Sweeteners on Body Weight Control and Glucose Homeostasis. Frontiers in Nutrition, [online] 7. doi:https://doi.org/10.3389/fnut.2020.598340.