Many studies have linked diet soda consumption to worse health outcomes. The researchers behind a 2017 study gathered data that indicated a link between diet soda and the risk of stroke and Alzheimer’s disease. The study involved 2,888 people over the age of 45 years. The results showed that drinking one diet soda per day almost tripled a person’s risk of stroke and Alzheimer’s disease.
A study of almost 60,000 women found that women who consumed one serving of diet soda per day were 1.4 times more likely to deliver preterm than those who did not—drinking diet soda while pregnant has been linked to some negative outcomes, including preterm delivery and childhood obesity.
Diet sodas may also undermine health by changing other habits. A 2012 study suggests that diet soda may change how the brain responds to sweet flavors by affecting dopamine. This neurotransmitter plays a role in pleasure, motivation, and reward. Frequently drinking diet soda might cause a person to crave more sweets, including sweet snacks and more soda.
A 2014 study of 2,037 male Japanese factory workers found that men who drank diet soda were more likely to develop diabetes than those who did not. The correlation held even after adjusting for family history, age, BMI, and lifestyle factors.
Early research suggested that there might be a link between artificial sweeteners and cancer. However, subsequent research has either found no link or questioned data that initially linked artificial sweeteners to cancer.
Research has linked a wide range of health risks to drinking diet soda. Despite being a low or zero-calorie beverage, it may still increase the risk of conditions such as diabetes and obesity. Diet soda offers no health benefits other than functioning as a tool that people can use to wean themselves off regular soda. While the precise relationship between diet soda and medical conditions is uncertain and requires more research, it is clear that people should not see diet soda as a healthful alternative to sugary drinks.