Caffeine is a natural component of tea and is considered safe when consumed in moderation. According to Health Canada, a balanced diet can include a moderate intake of caffeine with daily recommended consumption limits of between 400 to 450 mg. This is equivalent to 10-12 cups of tea per day. Actual caffeine levels in tea are dependent upon the specific blends and strength of the tea brew, but most servings contain only 25 to 34 mg. Tea contains one third to one half less caffeine than coffee.
6 Kim, Y.-I. (2000, October 03). Caffeine and Tea. Retrieved from Tea Association of Canada: http://www.tea.ca/Page.asp?PageID=376&ContentID=678&SiteNodeID=136