Diet soda and health: What a new study finds about daily consumption

If there's one beverage that continues to generate controversy in the health field, it's soda . Many opt for " diet " or " zero " versions in an attempt to avoid the side effects of sugar—but does this switch actually offer a benefit to the body? A new study challenges this idea.

The study, conducted by Monash University in Australia, showed that daily consumption of diet soda can increase the risk of developing type 2 diabetes by 38%. Even more surprising is that this risk was found to be higher than that associated with regular soda, whose daily consumption increased the risk by 23%. According to the authors, the explanation may lie in artificial sweeteners—such as aspartame —which appear to interfere with glucose metabolism.

To reach this conclusion, researchers followed 36,000 Australian adults, aged 40 to 69, over 14 years. The study was published in the scientific journal " Diabetes & Metabolism ."

This, however, isn't the only recent evidence on the potential impacts of diet soda. In 2024, another study, published in the American Heart Association's journal " Circulation: Arrhythmia and Electrophysiology ," linked the consumption of artificially sweetened beverages (such as zero-sugar soda) to a 20% increased risk of atrial fibrillation—a potentially serious cardiac arrhythmia. For this to happen, an average consumption of less than one can (350 ml) per day was sufficient.

Although many people turn to these beverages because they're sugar-free, the warning remains: soft drinks—even diet ones—are ultra-processed products with no nutritional value or metabolic benefits. Studies suggest that even calorie-free sweeteners can trigger an insulin response similar to sugar, in addition to negatively affecting the gut microbiome, which is essential for overall health.

The Food Guide for the Brazilian Population , developed by the Ministry of Health, already recommends that we avoid habitual consumption of ultra-processed foods. The World Health Organization has also discouraged the use of artificial sweeteners for weight control purposes.

Individually, these beverages don't pose an isolated risk. But frequent consumption, combined with their cumulative effect on the body, reinforces what science has shown: balance is key to the health equation.