(CNN) In the black hole of bad news for diet soda lovers, there's a tiny glimmer of light.

The gloom set in when science showed drinking diet soda could lead to metabolic syndrome, a nasty mix of higher blood pressure and blood sugars that leads to weight gain and increases the risk of diabetes, heart disease and stroke.

But a new study has found that it's when you pair the common artificial sweetener sucralose with a carbohydrate -- not the sweetener alone -- that the body's metabolism changes in a way that can lead to metabolic syndrome.

Theoretically, that means you could enjoy a sucralose-sweetened diet soda without negatively changing your body's metabolism if you drank it all by itself -- as long as it wasn't too close to eating a carb, of course.

"The question most people ask me is, 'Okay, so this means that I can have my diet soda if I drink it by itself, but how long do I have to wait?' We don't know that yet," said study author and neuropsychologist Dana Small, who directs the Modern Diet and Physiology Research Center at Yale University.

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