Bioethics Blogs

Taking a New Look at Artificial Sweeteners

Packets of artificial sweetenersDiet sodas and other treats sweetened with artificial sweeteners are often viewed as guilt-free pleasures. Because such foods are usually lower in calories than those containing natural sugars, many have considered them a good option for people who are trying to lose weight or keep their blood glucose levels in check. But some surprising new research suggests that artificial sweeteners might actually do the opposite, by changing the microbes living in our intestines [1].

To explore the impact of various kinds of sweeteners on the zillions of microbes living in the human intestine (referred to as the gut microbiome), an Israeli research team first turned to mice. One group of mice was given water that contained one of two natural sugars: glucose or sucrose; the other group received water that contained one of three artificial sweeteners: saccharin (the main ingredient in Sweet’N Low®), sucralose (Splenda®), or aspartame (Equal®, Nutrasweet®). Both groups ate a diet of normal mouse chow.

To their surprise, the researchers discovered that many animals in the artificial sweetener groups—especially those that drank saccharin-sweetened water—developed a condition called glucose intolerance, which is characterized by high blood glucose levels and is an early warning sign of increased risk for developing type 2 diabetes. In contrast, the animals that drank sugar water remained healthy.

The result was puzzling. These mice weren’t consuming natural sugars, so what was raising their blood glucose levels? The researchers had a hunch that the answer might lie in the gut microbiome—since those microbes play a vital role in digestion. Their suspicions were borne out.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.