Artificial sweeteners, sometimes touted as a healthier alternative to sugar, are used for calorie-free sweetening in products like diet sodas, chewing gum, and sugar-free candy. However, amidst their ongoing popularity, concerns have emerged about their potential effects on gut health. In this article, we’re going to cut through the noise and help you understand exactly what artificial sweeteners are doing to your body.

Your gut microbiome is intricately connected to your overall health and well-being. An imbalance in gut bacteria can lead to inflammation, impaired immunity, mood disorders, hormonal imbalance, and weight gain (1). According to a study in the journal Advanced Nutrition, artificial sweeteners disrupt the gut microbiome and its ability to effectively process nutrients.  They actually decrease gut bacteria such as Akkermansia muciniphila and Lactobacillus, both of which help maintain the gut lining and support metabolism (2).  

What’s more, studies are now finding that artificial sweeteners also negatively impact the body’s ability to regulate blood sugar, which ironically can lead to the very consequences that most people are trying to avoid by choosing sugar-free products: namely weight gain and diabetes (3). 

In a 2022 study published in the journal Cell, 120 healthy adults were split into six groups. One group was given no sweetener, one was simply given glucose, and the remaining groups were given common artificial sweeteners in doses well below acceptable daily limits. After two weeks, the researchers compared the gut microbes, blood sugar levels, and other health markers of each group. 

The study found that each artificial sweetener significantly changed the types and numbers of microbes in the gut and mouth as well as negative changes in blood sugar regulation, particularly for those participants who consumed saccharin and sucralose, while the two groups who received no sweetener or only glucose had no changes in their microbiome.

The researchers then transplanted gut microbes from study participants whose microbiome was strongly impacted by sucralose into mice and fascinatingly, the mice developed similar disruptions in blood sugar control. It seemed the microbes were communicating with the mice in a way that negatively changed their health.

So, while artificial sweeteners are approved as safe for consumption by regulatory agencies, their long-term and negative effects on gut health are still a subject of ongoing research. In the pursuit of healthier living, it’s essential to be mindful of the choices we make, especially when it comes to our gut health.

Artificial sweeteners may offer a sweet fix without the added calories, but their impact on our gut microbiota warrants a second thought before reaching for that “sugar-free” product. Opting for a natural alternative like monk fruit, or using small amounts of natural sweeteners like honey, blackstrap molasses, or maple syrup may be a better option for those seeking sweetness without the potential risks associated with artificial sweeteners.

1. Madison, Keicolt-Glaser. (2019). Stress, depression, diet, and the gut microbiota: human–bacteria interactions at the core of psychoneuroimmunology and nutrition. Curr Opin Behav Sci. 105–110.
2.  Ruiz-Ojeda, Plaza-Díaz, Sáez-Lara, Gil. (2019) Effects of Sweeteners on the Gut Microbiota: A Review of Experimental Studies and Clinical Trials. Adv Nutr. 2019 Jan; 10(Suppl 1): S31–S48.
3. Suez, Cohen, et al. (2022) Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell. Volume 185, Issue 18, P3307-3328.E19.