People love a startling headline, and diet drinks are always good for that. It’s often reported that diet drinks are worse for you than sugared drinks, which I think is usually a journalistic misstep. I believe the research consistently demonstrates problems with diet drinks relative to unsweetened drinks. Something harder to research is whether diet cola (with phosphoric acid and caffeine) doesn’t have liabilities beyond those of other drinks with non nutritive sweeteners. The particular activity of aspartame on phosphatases is also a confounding factor. Add to all this that diet cola is prevalent at restaurants and in grocery store offerings.
What is Oxidative Stress?
What is Insulin Resistance?
Why is phosphate so important?
The Diet Cola Paradox 