Yale researchers say artificial sweeteners can make healthy people sick if they are paired with this


Low-calorie sweeteners are supposed to be a healthy way to still enjoy the flavors we love. When these ingredients first burst on the scene many years ago they seemed almost too good to be true, and those feelings were vindicated when several recent studies concluded that low-cal sweeteners disrupt our metabolisms and even promote diabetes and obesity. 

Talk about a role reversal. These products are supposed to help people lose weight.

However, other recent research projects have come to conflicting conclusions; that food and drinks containing low-cal sweeteners are perfectly fine for our metabolisms and in all likelihood are a beneficial aid in the pursuit of weight loss.

So, which one is it? A team of Yale researchers may finally put an end to the debate. Well, sort of. 

This new piece of Yale researchers found that people who regularly drank beverages containing the low-calorie sweetener sucralose did, in fact, develop “problematic metabolic and neural responses.” Sucralose can be found in a wide variety of diet and low-cal soft drinks, candy bars, breakfast bars, and other food products. Splenda is produced using sucralose.

But, here’s the catch: these problematic reactions only occurred in participants if a carbohydrate in the form of a tasteless sugar had been added to their low-cal beverage. Conversely, participants who just drank the low-cal beverage or even a sugary drink didn’t experience any of the aforementioned metabolic or neural changes.

To put it in less scientific terms, it appears that low-cal sweeteners are only harmful when paired with some carbs. So, the next time you feel like a Diet Coke, just don’t drink it while eating some pasta.

“The subjects had seven low-calorie drinks, each containing the equivalent of two packages of Splenda, over two weeks,” says senior author Dana Small, professor of psychiatry and psychology and director of the Modern Diet and Physiology Research Center, in a press release. “When the drink was consumed with just the low-calorie sweetener, no changes were observed; however, when this same amount of low-calorie sweetener was consumed with a carbohydrate added to the drink, sugar metabolism and brain response to sugar became impaired.” 

The research team had originally wanted to test the notion that consuming low-cal sweeteners results in an “uncoupling” of one’s sweet taste perceptions and energy levels. Essentially, this theory suggests that regularly consuming low-cal sweetened products results in one’s body developing a “diminished physiological response” to even real sugar; no more sugar rushes or mood boosts. This phenomenon could conceivably lead to an overall more lethargic lifestyle, contributing to weight gain, diabetes, and glucose intolerance.

These results, though, disprove that hypothesis. Instead, pointing to the mixture of low-cal products and carbs resulting in metabolic impairment.

“The bottom line is that, at least in small quantities, individuals can safely drink a diet soda, but they shouldn’t add French fries,” concludes Small. “This is important information, particularly for people with diabetes who shouldn’t consume sugars.”

While this study provides some answers as to why previous studies have come to varying conclusions on the effects of low-cal sweeteners, its findings also raise a number of new questions. Why does the pairing of carbs & low-cal sweeteners result in detrimental metabolic changes? What role do our brains and neurons play in all this? We seriously shouldn’t eat fries with diet soda anymore?

If there’s one definite conclusion that can be drawn from all of this, it’s that manufacturers, scientists, and consumers alike don’t have a full understanding of how products like Splenda interact with one’s body chemistry.

The full study can be found here, published in Cell Metabolism.