Diet sodas increase waist size dramatically. Image courtesy of baileyraeweaver.

In an attempt to cut back on sugar and calories, many people turn to artificially sweetened diet soda to get their fix. However, two new studies suggest that not only does diet soda fail to help people lose weight, it may in fact contribute to weight gain by raising blood sugar and paving the way for type 2 diabetes.

In the first study, participants in the San Antonio Longitudinal Study of Aging (SALSA) were followed for an average of 9.5 years. Researches tracked height, weight, waist circumference and diet soda intake at several points throughout the study.

People who regularly drank diet soda showed an increase in waist circumference of 70% compared to those who did not drink diet soda. Worse, those who drank the most diet soda (more than two servings per day) showed a staggering 500% increase in waist size compared to non-drinkers.

While the biological mechanism by which diet soda may contribute to abdominal fat is still unknown, another study done using mouse that are more prone to diabetes suggests the artificial sweetener aspartame may be to blame. In this study researchers fed the mice food that either did or did not contain aspartame, the no calorie sweetener known commercially as Equal.

The mice fed the aspartame diet developed higher fasting glucose and lower insulin than the control group, indicating that the sweetener may contribute to the development of insulin resistance that could lead to weight gain and ultimately type 2 diabetes.

Both studies were presented at the American Diabetes Association’s Scientific Session conference in San Diego this week. The studies have yet to be subject to peer review.

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Diet Sodas May Not Be As Harmless As You Think 1 July,2011Darya Pino


Darya Pino

Darya Pino is a Ph.D trained scientist, San Francisco foodie, food and health writer and advocate of local, seasonal foods. She shares her unique scientific perspective on health and enthusiasm for delicious foods at her website Summer Tomato. Follow her on Twitter @summertomato.

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