Caffeine isn't great for you, (and as you've discovered, can lead to really dreadful withdrawl headaches) but for most people it's a lot less bad than being obese. Weight loss is hard enough without going through caffeine withdrawl...I say one thing at a time. If you're thinking about becoming pregnant, or you've been having major insomnia problems, kick the Diet Pepsi now and worry about weight loss when that's over with. If not, then drink your Diet Pepsi and be happy that your helpful little addiction usually costs less than my Diet Coke.
