I bought this after seeing Martin's podcast a couple of months ago. After doing some research I was very intrigued. It is formed when volcanic eruptions hit sea water and is essentially a crystal. I was taking SSRI antidepressants for 10 years and am convinced that even after being off them for over 3 years there are traces of it in my system. Prozac is approximately 20% fluoride (a heavy metal) that calcifies and shuts down the pineal gland. Whether this is intentional or not is open to argument. Also after mercury fillings from childhood and using Teflon non-stick pans for a long time as well, I'm sure there is a lot of heavy metals in my system. After just a few weeks, I feel a lot clearer and cleaner in myself. As Martin has stated, due to the current world situation with pollution, radioactivity not to mention whatever other junk is in the atmosphere, it is a good idea to take Zeolite. I highly recommend it.