Its not good. Caffeinated sodas are a diathetic and it will pull water out of your system. Check out ChubbyEmu’s Channel on YouTube for the explanation. If you have been drinking exclusively sodas since a child with no water in take you could be damaging your liver and kidneys. Also I would strongly suggest taking a muti-vitimin daily. Most diet sodas make it harder for you to absorb certain nutrients like folic acid and IIRC B-12.

If you were one of the people that Aspartame is an issue you would know it by know because almost every time you drank soda you would have a headache. You are probably getting more of them just from the dehydration.

Then there are the dental issues. I don’t care how old you are, start using sensodyne and look at having your teeth sealed. Your dentist can do wonders that were not possible 15 years ago, but that will give you issues.

Now a while back there was a thing about sodas and diet sodas raising your risk of Cancer but you would have to drink 6L+ a day. Lower amounts are believed to actually fight against cancer cells in their early stages.