Eat this stuff at your own risk.
Consuming high amounts of fructose (a type of sugar), artificial sweeteners, and sugar alcohols (another type of low-calorie sweetener) cause your gut bacteria to adapt in a way that interferes with your satiety signals and metabolism, according to a new paper in Obesity Reviews. (If you've noticed you've been feeling tired all the time and gaining weight, your metabolism may be slowing.)
"An evolution of the gut flora to this new sweetener-rich environment has a potential to negatively impact our health," says Amanda Payne, Ph.D., lead author of the review.
How does that happen? As bacteria in the gut process food, they give off byproducts called short-chain fatty acids. These can be beneficial and serve as energy in the body. But as the sweetener-adapted bacteria thrive and become more efficient at processing large amounts of high-fructose corn syrup, artificial sweeteners, and sugar alcohols, they also produce more and more short-chain fatty acids. (Not to imply that sugar is any better than artificial sweeteners.)
In those high amounts, Payne says, short-chain fatty acids decrease satiety signals. "This signaling may cause disruptions in our feeling full and hence prevent us from stopping to eat when we should," Payne says.