What kind of tea would you recommend?

I am currently having to chance some of my dad's diet (he is nto happy about it to say the least). He has had surgery for cancer and is now on the mend. But the doctor told us to change some of his diet. Being from the south my dad LOVES his iced sweet tea. But we need to cut the sugar and caffine. Anyone got any ideas of how I can make this change a little better on him? I have heard of putting honey instead of sugar in the tea. Anyone try this? Also are there flavored teas that taste good but do not have sugar or caffine in them?