How safe are fourth-generation sweeteners, such as the rare sugar allulose?
First, there was sugar and high-fructose corn syrup, the original industrial sweeteners. They were cheap, but they had lots of empty calories and contributed to diseases such as obesity, type 2 diabetes, cavities, and metabolic syndrome. Then came the second-generation sweeteners, the artificial sweeteners in the colored pastel packets: NutraSweet, Splenda, and Sweet’N Low. They have practically zero calories, but there have been reports of adverse effects, prompting caution. For example, artificial sweeteners were found to induce glucose intolerance by altering the gut microbiome, thereby producing “the counterintuitive effect of inducing metabolic derangements.” (They also taste kind of funny.) Enter the third-generation sweeteners: sugar alcohols, such as sorbitol, xylitol, and erythritol. They’re low-calorie sweeteners; however, their laxative effects can create difficulties. That brings us to rare sugars like allulose, which are natural sweeteners with a sugar-like taste and low or zero calories.
For those who haven’t heard of allulose, it’s been through a bit of a rebranding—kind of like the morphing of rapeseed oil into canola oil, which forced a Canadian community to update its town slogan,
