Artificial sweeteners are huge in the health industry. They tend to hold the blame for every unexplainable ailment that may happen. You aren't loosing weight? It can't be your mediocre diet, its the diet coke you drank last week.
Artificial sweeteners have indeed proven to have negative effects on glucose tolerance and potentially problems with gene expression. However this was in rats feed a high fat high sugar diet, much like the diet that is assumed to correlate highly with obesity. Conversely there have even been studies that show positive affects of sweeteners increasing "good" bacteria in the gut. So the data for sweeteners is very scattered and not fully understood.
SuppVersity does a great job of objectively analyzing data of the studies shown.
The study did infact show more significant data for aspartame versus acesulfame-K. However the subjects consumed significantly more aspartame than the other sweeteners in the study. So that correlation is then invalid.
Ultimately if you read the full article it is clear that although the data may be significant there is no way to effectively argue its efficacy in either direction.
The biggest take away from looking at the statistical data is:
"Eventually, the data (figure 1) shows us only one thing: The gut microbe is like a finger print. It's different for all of us and despite changes due to artificial sweetener consumption, there's no clear pattern in any of the artificial sweetener groups that would allow us to predict negative or positive effects based on what we know now."
Ultimately there is no final conclusion on what artificial sweeteners may actually do to your gut. We may inference that consuming 3-5 artificial sweetener containing products a day may not be beneficial. Also remember the negative effects shown were on rat subjects fed a hyper caloric high fat high sugar diet. Essentially I wouldn't stress on having a soda or bag of candy here or there. In the future we may or may not have a more conclusive answer but as long as your eating well and physically active you are probably moving down the right path.
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