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THE TRUTH ABOUT YOUR TEETH (BBC1, 9pm) HAVING just about recovered from his hangover after his recent binge drinking experiment, Dr Chris Van Tulleken, below, is back on TV to give himself gum disease.
It makes for some fascinating scientific discoveries, but he really is a glutton for punishment "I really hope my teeth don't fall out at the end of this experiment," he says.
Chris, telly presenter Jasmine Harman and leading dentist Serpil Djemal, have been working together to help fix Britain's teeth, with a clinic set up at London's Kings College Hospital. But now, in this second show, Chris is joining a clinical trial himself to see if looking after your smile can lead to a longer life.
His task is to not brush his teeth properly for three weeks - with the result that he clears a train carriage in seconds and his cat sprints off in the opposite direction.
"There's nothing worse than bad breath," says his wife, clearly appalled. But what has he done to his teeth? Meanwhile, back at the clinic, we meet Joe, 22, who has the teeth of a pensioner, and a little girl with the worst case of tooth decay they have seen.