Hot water stays in the stomach a little longer
Green tea has some acids, caffeine, and very few calories, but it is not the same as water. I don't find it as an equal substitute if you have both available. Tea is said to be a detoxify, but it is a different thing than water, to me.
For instance, in the early morning at work, I have a bit of decaffeinated coffee mixed with latte and hot water--and if I were to drink a hot tea right after, without food, I have a digestive upset with the acids of tea and coffee. However, hot water is benign and helps dilute the coffee.
Tea was originally used to flavor the heated water and helped purify the local waters of contaminents. However I am thinking of Chinese and Japanese green tea. I get them in discount teabag packets at a superstore known as Costco. I also do not heavily flavor my hot water during the evening with loads of teabags.
I am not thinking of Lipton's or cheaper grades of green tea. I don't know all the differences, I just don't like Lipton's green tea.
Hot water, plain, is similar to the characteristics of drinking cooler water, but it is said to stay in the stomach longer. My father will drink hot water at night, not herbal or green tea, to keep away from caffeine.
We're conservative, with funny stomachs, though--in my father and sister's case, it was experience with ulcers. Nothing to do with their liking of tea, it's said, but they watch their intake. Workouts where one sweats out toxins and stress might also have helped me avoid ulcers so far.
Someone else may be able to give you better advice. I hope you have good experiences in whatever you choose....and I hope what I said might help.
Good health to you!
Cerulean
Regards,
Cerulean