The Potential Negative Effects of Artificial Sweeteners on Gut Health

Reading Time: 6 minutes

Artificial sweeteners have become popular in the food and beverage industry, commonly found in everyday “health” products like recovery drinks and protein bars. Despite being recognized as safe by the FDA, a growing body of research suggests that these sugar substitutes may not be as harmless as we once thought, especially when it comes to artificial sweeteners and gut health. 

In fact, a 2014 study found that artificial sweeteners have the ability to alter gut microbes, potentially contributing to the modern epidemic of metabolic disease. In this article, we’ll dive into the details of this study and explore how artificial sweeteners may be affecting the health of your microbiome. 

Unpacking the Health Risks of Non-Caloric Artificial Sweeteners: Artificial Sweeteners and Gut Health

artificial sweeteners and gut health

Non-caloric artificial sweeteners (NASs) have become increasingly popular in recent years as a sugar substitute due to their low-calorie content. The worldwide market for high-intensity sweeteners surpassed 6.37 billion in 2020 and is expected to continue to grow between 2023-2028. Similarly, the non-nutritive category is projected to experience significant growth in the coming years. (1)

In the United States, six NASs have been approved for use, including aspartame, sucralose, neotame, acesulfame potassium (Ace-K), saccharin, and advantame, all of which have been deemed Generally Recognized as Safe (GRAS) by the FDA. (2)

Despite their widespread use and apparent safety, research has shown that NASs can have negative effects on gut health. Most NASs pass through the human gastrointestinal tract without being digested, coming into direct contact with microbes in the colon. (3)

This interaction can have dramatic implications for the health of the host. In fact, a 2014 study found that consumption of NASs can cause glucose intolerance, potentially contributing to metabolic disease. (4) As we delve deeper into the study’s findings, we’ll explore the potential impacts of artificial sweeteners on gut health and overall wellness.

How Non-Caloric Artificial Sweeteners May Be Harming Your Health: Insights from a Study on Glucose Intolerance in Mice

Researchers from the Weizmann Institute of Science in Israel conducted a study which revealed that lean 10-week-old mice developed significant glucose intolerance when saccharin, sucralose, or aspartame were added to their drinking water. To test this, the researchers conducted a glucose tolerance test on the mice, comparing them to control groups drinking only water or water supplemented with glucose or sucrose.

At week 11 of feeding, the control groups had comparable glucose tolerance curves, while all three NAS groups had developed significant glucose intolerance. Interestingly, saccharin had the largest effect. To confirm their findings, the researchers conducted the same experiment on diet-induced obese mice and observed the same results: NAS consumption made the obese mice more glucose intolerant.

This finding is significant as glucose intolerance is a key factor in the development of metabolic diseases such as diabetes. The study suggests that prolonged consumption of non-caloric artificial sweeteners may contribute to the modern epidemic of metabolic disease. Further research is needed to explore the potential long-term effects of NAS consumption on human health.

NAS Alters Microbiota Composition and Function: What This Means for Your Health

The study conducted by researchers from the Weizmann Institute of Science in Israel found that mice consuming saccharin (a non-caloric artificial sweetener) had a different mix of gut bacteria from those that did not consume it. They found an overgrowth of harmful bacteria and a decrease in beneficial bacteria.

Moreover, the researchers found that mice consuming saccharin had a marked upregulation of genes related to glycan degradation pathways, which have been linked to increased energy extraction and metabolic disease.

In a follow-up experiment, the researchers transferred fecal material from mice who had consumed saccharin to other mice who had not. These mice developed increased glucose intolerance, a risk factor for metabolic disease, and similar changes in their gut bacteria.

These findings suggest that non-caloric artificial sweeteners may have a negative impact on gut health and metabolism. (5) Dysbiosis and altered microbial function have been linked to a variety of health issues, including metabolic and heart disease, bladder cancer and inflammation. While the study was conducted on mice, it raises concerns about the potential long-term effects of non-caloric artificial sweetener consumption on human gut health.

As we continue to learn more about the gut microbiome, it’s becoming increasingly clear that what you eat can have a significant impact on your health. It’s important to be mindful of your dietary choices and consider the potential long-term health effects both on your gut health and overall well-being.

Negative Impact of NAS Consumption on Human Gut Health and Metabolic Disease

A cross-sectional study on humans found that NAS consumption was positively correlated with several measures of metabolic disease, including weight gain, waist-to-hip ratio, fasting blood glucose, hemoglobin A1c, glucose tolerance test, and ALT. The effect still remained even after correcting for BMI. These findings suggest that NAS consumption may have significant negative effects on gut health, weight loss and metabolic disease, highlighting the need for further research and caution in the consumption of NAS.

The Takeaway: Artificial Sweeteners and Gut Health

In conclusion, the impact of non-caloric artificial sweeteners on gut health and metabolic disease cannot be overlooked. Studies in mice have shown that prolonged consumption of NAS can lead to glucose intolerance, dysbiosis of gut microbiota, and alterations in microbial function. Furthermore, a cross-sectional study in humans has shown a significant positive correlation between NAS consumption and several measures of metabolic disease. 6

While NAS are deemed safe by the FDA, these findings suggest the need for caution in their consumption and highlight the importance of being mindful of what’s in your drinks and food products. As always, a balanced and varied diet is key to maintaining good health, and it’s essential to prioritize whole, minimally processed foods whenever possible. By making informed choices and taking steps to support gut health, we can help prevent metabolic disease and promote overall well-being.

Lyvecap STRONG reimagines recovery with a health-first approach. Equipped with 200 billion CFUs of live bacteria, alongside amino acids Leucine and Taurine, STRONG supports performance, recovery and overall wellness. Shop STRONG today, a premium probiotic for athletes. 

Artificial Sweeteners and Gut Health: FAQs

Are artificial sweeteners harmful?

There is some evidence that suggests long-term consumption of artificial sweeteners could potentially harm gut health, disrupt blood sugar regulation and contribute to metabolic diseases like diabetes. However, the FDA has deemed its approved artificial sweeteners as safe for consumption in moderate amounts.

What is the safest artificial sweetener to use?

There is no clear answer to this question, as it largely depends on individual preferences and sensitivities. However, some commonly used artificial sweeteners that have been deemed safe for consumption include stevia, erythritol, and monk fruit extract.

Are artificial sweeteners worse than sugar?

While artificial sweeteners are marketed as healthier alternatives to sugar due to their low-calorie content, some studies suggest that they may have negative impacts on gut health, blood sugar regulation, body weight, and metabolic health. However, consuming excessive amounts of sugar has also been linked to a number of negative health outcomes, including obesity, type 2 diabetes, and cardiovascular disease.

What artificial sweeteners to avoid?

Artificial sweeteners like saccharin, aspartame, and sucralose have been associated with potential negative effects on gut health and metabolism in some animal studies. However, it’s important to note that the FDA has deemed these sweeteners safe for consumption in moderate amounts.

What sweeteners should I avoid?

Some common sweeteners that are associated with negative health outcomes include high fructose corn syrup, which has been linked to obesity and metabolic diseases, and artificial sweeteners like saccharin, aspartame, and sucralose.

What do artificial sweeteners do to your body?

Artificial sweeteners can have a range of effects on the body, depending on the type and amount consumed. Some studies suggest that they may negatively impact gut health, blood sugar regulation, and metabolic health. Additionally, consuming excessive amounts of artificial sweeteners can potentially lead to negative health outcomes.

What are the symptoms of artificial sweetener intolerance?

There is limited research on artificial sweetener intolerance, and as a result, there are no established symptoms that are specifically associated with it. However, some people may experience digestive discomfort or gastrointestinal symptoms such as bloating, gas, or diarrhea after consuming artificial sweeteners.

In some cases, individuals with a sensitivity to specific types of artificial sweeteners may experience allergic reactions, such as itching, hives, or difficulty breathing. It is important to speak with a healthcare provider if you suspect that you may have an intolerance or sensitivity to artificial sweeteners.


  1. “Global High-Intensity Sweeteners Market Report and Forecast 2023-2028.” High-Intensity Sweeteners Market Size, Share, Analysis 2023-2028,
  2. Center for Food Safety and Applied Nutrition. “Generally Recognized as Safe (GRAS).” U.S. Food and Drug Administration, FDA, 
  3. Le Roy, T., Clément, K. Bittersweet: artificial sweeteners and the health benefits of gut microbiome. Nat Med 28, 2259–2260 (2022).
  4. Suez J, Korem T, Zeevi D, Zilberman-Schapira G, Thaiss CA, Maza O, Israeli D, Zmora N, Gilad S, Weinberger A, Kuperman Y, Harmelin A, Kolodkin-Gal I, Shapiro H, Halpern Z, Segal E, Elinav E. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature. 2014 Oct 9;514(7521):181-6. doi: 10.1038/nature13793. Epub 2014 Sep 17. PMID: 25231862.
  5. Del Pozo S, Gómez-Martínez S, Díaz LE, Nova E, Urrialde R, Marcos A. Potential Effects of Sucralose and Saccharin on Gut Microbiota: A Review. Nutrients. 2022 Apr 18;14(8):1682. doi: 10.3390/nu14081682. PMID: 35458244; PMCID: PMC9029443.
  6. Shil A, Olusanya O, Ghufoor Z, Forson B, Marks J, Chichger H. Artificial Sweeteners Disrupt Tight Junctions and Barrier Function in the Intestinal Epithelium through Activation of the Sweet Taste Receptor, T1R3. Nutrients. 2020 Jun 22;12(6):1862. doi: 10.3390/nu12061862. PMID: 32580504; PMCID: PMC7353258.