Aspartame makes you gain weight, so all other ill affects aside, the "Diet" in Diet Coke isn't doing what you would like it to do. Just drink the regular stuff if you must
Is the "Diet" Coke Chemical Making You Fat?
This fact sheet describes the scientific evidence that ties aspartame – the artificial sweetener found in Diet Coke, Diet Pepsi and thousands of other food products – to weight gain, increased appetite, diabetes, metabolic derangement and obesity-related diseases.
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