Basically, the idea of gaining better health is to follow the laws of Nature. All man-made / processed materials that do not occur in nature are potentially toxic.
I didn't have mercury fillings myself (thank god), but I did have permanent retainers, fissure sealants, and other types of fillings on my teeth. No matter how "non-toxic" the dentists or scientists claim they are (after doing lab tests), there is always a possibility that these man-made materials are toxic in some unknown way - humans can never know everything about a substance. Take the example of drugs being taken off the market 10-15 years later when scientists finally realize how dangerous they were. It is impossible or very very hard for humans to outsmart mother nature.
I didn't have mercury fillings myself (thank god), but I did have permanent retainers, fissure sealants, and other types of fillings on my teeth. No matter how "non-toxic" the dentists or scientists claim they are (after doing lab tests), there is always a possibility that these man-made materials are toxic in some unknown way - humans can never know everything about a substance. Take the example of drugs being taken off the market 10-15 years later when scientists finally realize how dangerous they were. It is impossible or very very hard for humans to outsmart mother nature.