Numerous health claims have been made about components of green tea, notably phytochemicals called catechins. The jury's still out on many of these claims; a review published last summer concluded there isn't solid evidence that green tea prevents certain types of cancer, for example. If you are in pursuit of any potential benefits from tea, though, you don't need to limit yourself to green. Studies have shown that people who drink black and green tea have fewer heart attacks (though those studies cannot prove that tea is the cause). Meantime, coffee—also full of antioxidants—may have its own health benefits for people who aren't pregnant or sensitive to caffeine.