This may seem like a given at first, especially since they are called “bamboo” comforters, after all. However, while they are supposed to be filled with bamboo, some companies do use polyester fiber fill. That’s why it’s super important to check the tag before you make your purchase. If you’re not careful, you might wind up purchasing the wrong type. In turn, it can lead to a poor night’s rest or even paying too much for something with cheap filler ingredients.