Do Diet Drinks Mess Up Metabolisms?

It may seem counterintuitive, but there’s a body of evidence to suggest that the millions of Americans with a diet soda habit may not be doing their waistlines — or their blood sugar — any favors. As the consumption of diet drinks made with artificial sweeteners continues to rise, researchers are beginning to make some uncomfortable associations with weight gain and other diseases.
 
For instance, as researcher Susan Swithers writes in a new opinion piece published in the journal Trends in Endocrinology and Metabolism, "accumulating evidence suggests that frequent consumers of these sugar substitutes (such as aspartame, sucralose, and saccharin) may also be at increased risk of … metabolic syndrome, type 2 diabetes and cardiovascular disease."
 
If you listen to my conversation on Here & Now, you’ll hear that there are two schools of thought here. Not everyone is convinced that diet soda is so bad.
 
For instance, a study I reported on last year by researchers at Boston Children’s Hospital found that overweight teens did well when they switched from sugar-laden drinks to zero-calorie options such as diet soda.
 
But it’s also hard to ignore the gathering body of evidence that points to potentially bad outcomes associated with a diet soda habit.
 
One example: the findings of the San Antonio Heart Study, which pointed to a strong link between diet soda consumption and weight gain over time.
 
"On average, for each diet soft drink our participants drank per day, they were 65 percent more likely to become overweight during the next seven to eight years" said Sharon Fowler, in a release announcing the findings several years back.
 
Another bit of evidence: A multi-ethnic study, which included some 5,000 men and women, found that diet soda consumption was linked to a significantly increased risk of both type-2 diabetes and metabolic syndrome.
 
So, what gives? How could consuming less sugar set the stage for more weight gain and an increased risk of disease?
 
Well, since being overweight is a major contributor to the development of type 2 diabetes, it’s possible that some diet-soda drinkers suffer from a mindset problem: They justify eating lots of high-calorie foods because their drinks are calorie-free.