you can drink any leaf tea on this diet so no flowery tea like camomile or jasmine or the fruity teas like lemon etc. I usually have peppermint tea which is lovely and refresing. Also you can drink black coffee and my CDC also said I could have a sweetner with this if I needed it.
Yes, since I started drinking my coffee black I've discovered that adding a sweetener makes it much more palatable, even though I don't usually take sugar in my coffee. It also eases any "need something sweet" cravings I sometimes get. I'm developing quite a taste for it now!
Can't stand black tea, though, even with sweetener - just tastes stewed!