There are a number of reasons fermented foods (yogurt, sauerkraut, kefir, tempeh, kimchee etc…) are becoming known as superfoods. Where did they come from? One of their properties is that they are harvested foods prepared for storage that can be held safely at room temperature. Fermented foods have bacteria and yeasts in them (known as probiotics), either naturally occurring or inoculated, that have been allowed to eat part of the food to create an acid and some alcohol byproducts. This causes the characteristic flavor and properties of the food. When we consume the fermented food, we not only eat the original substrate, but also the bacteria and yeast population, which have an effect on our internal flora. The probiotics can break down cellulose making the food more digestible and also give off their own byproducts, which we need for good health. We also have an internal microflora in our intestines that provides nutrients and vitamins, and eating certain foods (fiber) keeps them happy. For example Vitamin K which we desperately need for blood clotting, is entirely a product of our gut bacteria.