The food industry adds sweeteners because consumers love them, and foods with sweeteners sell better. Read Cooks Illustrated for a few months and note how many of the winning recipes are balanced with a sweetener of some sort. Extraneously-sweetened foods are not going away.
Being careful about what you eat: good. Rubber chicken health claims: not so good.
If you really need to try and drink something other than water I would recommend Apple juice. It's really the only thing you can find that is 100% pure all the time. Even OJ isn't something especial if it's from MinuteMaid.
For taking breaks I would recommend a few applications a computer geek can download.
Mac OSX: TimeOut: http://www.dejal.com/timeout/, AntiRSI: http://tech.inhelsinki.nl/antirsi/
Linux: Workrave: sudo apt-get install workrave or http://dag.wieers.com/rpm/packages/workrave/
Windows: Workrave works for windows as well, Bigstretch: http://www.monkeymatt.com/bigstretch/
That's a great idea, I'm going to edit the article and add those links!
It's hard to be disciplined when your really into the code so having something to trigger you to take a break is very useful.