If you want to make tea then you must get properly brewed tea which is made from high quality tea leaves, by using tea from high quality leaves makes you to add less sugar in tea which in turns means less gain in weight. Go to local tea shop owner and ask for tea which is obtained from large leaves which is often less bitter in taste. Yes, you got the idea less bitter equals adding of less sugar.
The next alternative which you can use in the morning is black tea which if you use you get a boost in energy because it contains most of caffeine. You can use green tea and white tea but it will contain less caffeine effect. You can also use herbal teas but it will depend on the taste ask the shop owner to help you out in this or you can try some of herbal teas for yourself by getting samples of it, after that all you need is hot water and add couple of leaves to it, that's it you got yourself a nice cup of herbal tea. My friend drinks in the night almost 5 cups, yes 5 cups, but he uses some leaves and keeps on refilling it with hot water, do you know drinking hot water with some herbal leaves in it keeps your stomach fit and strong ? If you don't believe it you can ask any Chinese guy it's in there tradition :).
Now for the coffee, most of us think that if you don't add cream and sugar to coffee it will taste very terrible or bad. Let me tell you the fact if you use old coffee then it will be terrible without them. But if you use coffee beans if you crush them in machine, beans release oils which have unique flavor and essence. If you use this coffee you won't be needing any type of cream and sugar. So best is to buy coffee beans and crush then by yourself, trust me people you will feel the difference of coffee it will be so much better in taste and will give you unique essence.
Yes it is true that when you are on diet you have to avoid drinks but you can't ignore just one cup in the morning.