Do Low- and No-Calorie Sweeteners Affect Gut Microbiota?

This blog was created in partnership with Tate & Lyle


Gut health is a hot topic these days, and for good reason! The health of your gut plays a major role in your overall well-being, from digestion to immune function and even mental health. At the same time, low- and no-calorie sweeteners (LNCS) are growing in popularity, offering a way to enjoy sweetness without the added calories and sugar. But how do these sweeteners impact your gut microbiota—the trillions of microbes that live in your gastrointestinal tract? 

This blog explores the effects of LNCS on gut microbiota, focusing on a new study that sheds light on this topic. We’ll break down the research findings and share practical tips to help you make choices that work for your health and lifestyle. 

What Is the Gut Microbiota, and Why Does It Matter? 

Your gut microbiota is a bustling community of bacteria, fungi, viruses, and other microorganisms living in your digestive tract. While some of these microbes can be harmful, most are incredibly beneficial, helping with tasks like breaking down food, producing essential nutrients, and supporting your immune system. This balance is key—when the “good” and “bad” bacteria become unbalanced, it can lead to digestive problems, inflammation, or even chronic diseases. 

Your diet has a huge impact on your gut microbiota. What you eat—whether it's fiber, protein, fats, sugar, or even LNCS—shapes which microbes thrive and which ones struggle to survive. Given how much your gut impacts your health, making mindful choices about your diet is one of the best ways to support a healthy microbiota.

The Study at a Glance 

A new study published in the International Journal of Food Sciences and Nutrition investigated how different types of LNCS impact the gut microbiota of healthy individuals and those with type 2 diabetes ex-vivo (e.g. when organ, cells, or tissues are taken from a living organism and studied in a lab with minimal alterations to the organism’s natural conditions). Researchers used a cutting-edge technology called SIFR® to analyze the potential effects of six sweeteners—tagatose, maltitol, sorbitol, stevia, sucralose, and acesulfame K. 

Here’s what the researchers found, explained simply: 

  • Not all sweeteners are the same. 

  • Some sweeteners, like sucralose and acesulfame K, remained mostly intact in the gut and didn’t significantly change the gut's microbial composition or metabolite production. 

  • Others had more notable effects. Sweeteners like tagatose, sorbitol, maltitol, and stevia were fermented by gut bacteria, which led to increases in bacterial density and the production of short-chain fatty acids (SCFAs), which may support gut health.

  • Compound-specific differences matter. For example, tagatose boosted butyrate for healthy subjects but increased propionate for those with type 2 diabetes. Similarly, sorbitol increased acetate production, while stevia and maltitol raised propionate levels. These SCFAs are important molecules that act as fuel for gut cells and provide other health benefits. 

The key takeaway? Low- and no-calorie sweeteners don’t all behave the same way in the gut. Their effects are highly specific to the compound, stressing that results for one sweetener can’t be generalized to others.

Key Findings 

This research revealed some insightful information about the interaction between low- and no-calorie sweeteners and gut health:

  • Sweeteners such as sucralose and acesulfame K seem to have minimal impact on gut microbial balance. 

  • Stevia and other fermentable sweeteners can support beneficial changes under certain conditions, like increasing bacterial density or SCFA production. 

  • The effects of these sweeteners may vary depending on a person’s gut microbiota, particularly for those with conditions like type 2 diabetes. 

This study begins to address several misconceptions about the impact of LNCS on gut health. While previous research suggested that LNCS might adversely impact the gut, this study underscores that the reality is far more nuanced and depends on the specific sweetener used, with some having no effect or even positively influencing the gut microbiota. 

Tips to Support Gut Health 

Maintaining a healthy gut doesn't have to be overwhelming! Here are a few practical tips to nurture your microbiota:

  • Eat a fiber-rich diet. Fiber from fruits, vegetables, whole grains, and legumes feeds the beneficial bacteria in your gut. 

  • Stay hydrated. Water helps keep your digestive system moving smoothly. 

  • Enjoy fermented foods. Yogurt, kefir, kombucha, and kimchi are rich in probiotics that support gut health. 

  • Opt for sweeteners that work best for you. With a variety of LNCS available, it’s also important to recognize that everyone's body is different, so keep an eye on how you feel and find what works best for you.

Closing Thoughts 

Your gut microbiota is vital to your well-being, and the choices you make—both big and small—can help support it. Low- and no-calorie sweeteners can be an effective tool to help reduce added calories and sugars. Exciting new research also suggests they can support your gut health, offering an encouraging perspective on their benefits. With thoughtful choices, you may be able to enjoy the sweetness in life and prioritize your well-being. The key is being mindful, understanding the nuances, and staying balanced in your overall diet and lifestyle. Remember, when it comes to your well-being, small steps can lead to big changes over time!

Lauren Manaker