Like "I don't think that any amount (of any kind of) tea would have a direct impact on blood glucose levels. I do believe that long-term use of stimulants (in caffeinated tea) has been known to help with weight loss though, and that blood glucose levels are generally more stable when you are not obese. If you are only drinking tea to wash down a triple Whopper while you lay on the couch all day, don't expect tea, diet pills or any other diet aid to help you lose weight and stabilize blood glucose levels. If used in conjunction with proper diet and exercise though, it may have benefits in the long run."