text: is diet coke and/or pepsi really diet? i've heard rumors that they will make you gain weight as much as reg   yea, as with what everyone else said thus far, here's another fact: one of the substitute sugars they've been inserting in low calorie/diet foods and drinks, i think the amphet..somethingsomething, isn't even digestable to us humans. it's a total manufactured chemical that our bodies are no knowledge or digestive bacteria to properly digest it. therefore, it is not good for you. i'd say diet sodas are worse than regular sodas, period. if you want a soda, drink a regular. otherwise, here's another fact: you can lose an average 10lbs in one year just by cutting soda out of your diet completely. think about that. the shet is useless to begin with.