I would like to understand why it is that heating foods over 104 degrees destroys the enzymes and nutrition but boiling herbs in water doesn't. I'm making and drinking Essiac tea and the information lists all the nutrition in the herbs ..slippery elm, burdock, sheep sorrel and rhubarb. I would think that boiling the herbs would also destroy the nutritional benefits. It doesn't make sense to me. Any accurate information available on the subject?