8 Potential Side Effects of Consuming Too Much Diet Soda. 1. Could disrupt gut health 2. Erodes tooth enamel 3. May cause headaches 4. Could decrease bone density 5. May affect heart health 6. Might be associated with sugar cravings 7. Might be related to weight gain/obesity 8. May be linked to type 2 diabetes Although diet soda has no calories, sugar, or fat, it has been linked to the development of type 2 diabetes and heart disease in several studies. Research has found that just one serving of an artificially sweetened drink per day is associated with an 8–13% higher risk of type 2 diabetes