Some numbers on Nutrition Facts published by Chinese Tea Museum.
Protein 20-30%
Polyphenols 20-30 %
Total carbohydrate 35 – 40%
Minerals 4-7%
Vitamins 0.6 – 1.0%

Numerous studies have suggested that drinking tea has the following benefits:
Helps prevent blood clotting and lowers cholesterol level
Reduces blood pressure
Relieves atherosclerosis
Reinforces the immune system
Helps digestion

Dos
Drink 4 cups of tea daily.
Drink tea according to the season.

Don’ts
Try to avoid drinking tea too dark.
Don’t drink tea on an empty stomach.
Don’t drink tea at bed time.
Don’t let tea sit for hours.