Is tea keto? How to drink tea on a keto diet - Simple Loose Leaf A cup of green tea, pure, unsweetened and unadulterated, will have around 2 calories, with a negligible amount of carbs. Green tea may help with fat burning and lose weight faster, and it may give a much-needed energy. Extra ideas: Make a morning energy boosting smoothie with powdered green tea, keto friendly protein powders and raw frozen spinach.