Match tea is a powder made from green tea that you can mix into drinks (from straight matcha to smoothies and more) and food. It's been popular with Japanese tea aficionados for years, but it's become a major player in hip and healthy circles in the West. It may seem like a strange supplement, but at its heart, it's tea, and there are some times when using matcha egcg is a good idea.
You Want Green Food
A popular use for matcha power is as food coloring, and it's likely better for you than an artificial coloring. Matcha will give your food a grassy, lighter green color and not a deep emerald, but if all you need is for the food to be green, and not a particular shade of green, matcha is best. You can find food-grade cooking matcha powders (as opposed to matcha meant for drinking) so you can save the really tasty stuff for tea.
You Like the Flavor
Of course, the most obvious reason to use matcha is that you like the flavor. Forget the health benefits from catechins and antioxidants; the real reason to try matcha is to have yet another tea to drink when you want. It's always better when the food or drink you have is healthy, but in the end, taste matters the most because you won't eat or drink something that doesn't taste good, especially if that taste affects any other ingredients in your meal.
You Need a More Robust Drink When Giving up Coffee
Matcha contains caffeine, so if you have to avoid all caffeine, it's not an appropriate choice. But if you're just cutting back on your caffeine intake by giving up coffee, and plain tea -- the type you steep -- isn't helping, the slightly thicker texture of matcha may be what you need. You're dissolving a powder into the tea instead of merely flavoring water, so you may get more of a robust experience drinking matcha instead.
You can find matcha in plenty of places, and like any food, there are good and bad brands. Keep experimenting; if you don't like it at first, try another brand or store to ensure you have a chance to try high-quality matcha. Given its health benefits -- the fact that you're ingesting the entire tea leaf and not just an essence steeped in water means you're getting a more concentrated dose -- matcha is worth a try.