I'm a Southern boy. Iced tea is part and parcel of my existence—a sweet and robust ying to my yang. It is the yardstick I use to judge restaurants—if it tastes a little off, it means the carafes probably aren't clean or the brew has been sitting out too long, which leaves the mind to wonder how the rest of the kitchen is kept. But more importantly, tea is how I make it through the day, by grace of its caffeine content. I was especially excited when I learned that Celestial Seasonings started offering its Fast Lane blend once again. This mix of tea and spices has additional caffeine added in, but the product only sporadically hits the market—the McRib of teas, if you will. Well, the flavor is worlds better than molded pork product swimming in barbecue sauce, but you get the idea.
But how does the caffeine content in tea stack up against coffee, soda and energy drinks? The Mayo Clinic was happy to oblige with a handy little tool using data from the USDA nutritional database to show you how our favorite pick-me-up potables compare. Here are a few highlights, with caffeine content expressed in milligrams:
Generic brewed coffee (8 oz.): 95-200 milligrams Black brewed tea (8 oz.): 40-120 milligrams Red Bull (8.3 oz. can): 76 milligrams Mountain Dew (12 oz. can): 54 milligrams Coca-Cola Classic (12 oz. can): 35 milligrams
Why is there wild variation in brewed caffeine products? A few factors affect a drink's ability to give you a buzz. With coffee, caffeine content varies depending on how beans are roasted and ground, and with tea, brewing time affects how much punch your cup is packing. The Fast Lane brew, per the product's website, clocks in at an average of 110 milligrams per 8 ounce cup, which while not as strong as cup of coffee could be, is still a pretty good jolt.
Lots of studies have been done on the effects of caffeine on human physiology, and the general consensus is that, taken in moderate amounts, you shouldn't have too much trouble. But if your regular intake exceeds 500 to 600 milligrams—or if you experience side effects such as anxiety, tremors, trouble sleeping or nausea—you should seriously consider cutting back. (There is some debate as to how much caffeine is safe for women who are pregnant or breastfeeding, though moderation—though the definition of that term varies depending on who you ask—seems to be key.)
Furthermore, a Johns Hopkins University study argues that caffeine withdrawal—that godawful state where you're headachy, irritable and can't concentrate, among other things—is a bona-fide mental disorder. Caffeine is technically a drug—the most widely ingested one in the world—so it's perfectly fitting that it should have its own set of medically-recognized issues. Is my own 2-ish quarts of tea a day habit a bit much? Perhaps. Just the same, I feel no shame at a restaurant when my waiter-cum-drug mule decides to save himself some trouble and just leaves me the whole carafe on the table. All of it is always enjoyed.