"At the end of the day, it's a heavy metal and it's not something that I want to have in my mouth anymore. It's been there long enough and I don't know what it's been doing to me and I would quite like to get rid of it." After feeling lethargic for some time, keen runner Ruth Goodwin began to wonder if the mercury amalgam fillings in her mouth could be contributing to her ill health. She was prepared to pay up to $3000 to have them removed along with a six-month detox. During the process, her dental team needed to wear gas masks to protect themselves from the increase in mercury vapours that could come from the drilling process. Best-selling author Terry Pratchett, who was diagnosed with Alzheimer's Disease last year, has also paid a small fortune to have his mercury amalgam fillings out. Although there is no conclusive scientific proof, he tells Tonight that he believes they may have contributed to the onset of his disease. The Alzheimer's disease trust says it would fund any serious research into a link. He says: "For me it was a no brainer. Having something like mercury in your mouth, no matter what the small print said seemed to me to be a really bad idea, and since I could afford it, I got rid of the stuff." Mercury fillings have been used for more than a hundred and fifty years. Two million of them were fitted in the UK last year alone.

Film Duration: 24 min .