Forget the Diet Soda

Those who drink diet soda thinking it will help them shed unwanted belly fat may see their waistlines expand instead. New analyses from an observational study of San Antonio men and women age 65 and older seem to indicate this. Data on the health status and lifestyle of approximately 500 people were collected over 9 years and were recorded at the beginning of the study and at each of three follow-up visits.

Results among participants varied according to their diet soda intake:

• Never consumed diet soda – waist increased less than 1 inch
• Occasional consumption (less than 1 per day) – waist increased about 2 inches
• Regular consumption (one or more a day) – waist increased over 3 inches

These findings raise a red flag for seniors because fat around the waist (the proverbial tire around the middle) includes not only fat just under the skin but also fat that accumulates around internal organs. Many studies have linked organ fat with increased inflammation and risk of metabolic disease, diabetes, heart attack, stroke, cancer, and mortality. When waistlines expand in older age, organ fat increases disproportionately, and the risk rises. The increases in abdominal fat were more than 3 times as great in daily diet soda users as in non-users, during the very time in life when increasing waist circumference is associated with increased risk of these serious medical conditions, and mortality itself.

The findings were in people age 65 and older; whether they would apply to younger people is not known. The findings were also most pronounced among those who were already overweight or obese at the outset of the trial. Bottom line – this study provides some evidence for meaningful decision-making regarding diet soda intake that may improve public health and the health of individuals.