Dr Feelgood: Can a toothpaste be worth £15?

Your weekly health and beauty check-up

Under the microscope: SwissDent Nano-Whitening Toothpaste, £15 for 100ml

In theory: According to one stockist, SwissDent's home-bleaching toothpastes "provide solutions for people who want beautiful teeth but do not want to forgo the small temptations that life offers". The paste creates calcium peroxide in nano-sized molecules that penetrate widely for optimum bleaching, while the combination of added Vitamin E, Coenzyme Q10 and fluoride should result in "beautiful gleaming teeth and healthy oral flora".

In practice: An expensive toothpaste is usually identifiable by a lack of foam, and this one was a bit like brushing with wallpaper paste. That said, it did leave Dr F with the impression that she had a thin coating on her teeth – presumably pretty important if it is going to have any bleaching or protective effect.

Observations: SwissDent had a tough job with Dr F's not-so-pearly-whites, since black coffee, Marlboro Lights and red wine are her favourite food groups (sorry Mum!) but there was some improvement, albeit very slight. One friend made an unsolicited comment on the whiteness of her teeth, but perhaps it was just a flattering shade of lipstick, as Dr F's dentist wasn't convinced.

Analysis: The idea that you can have your cake – or, in this case, coffee – and eat it is always tantalising but, like most whitening toothpastes, this seemed too mild to really get to work on discolouration. Even in-surgery whitening treatments tend to result in only subtle improvements, so to expect a Hollywood smile from a toothpaste is probably asking a little too much. Old staining will need more shifting, but this should at least protect against any further problems.

Prescription: If you are happy to spend a bit more on your toothpaste, this is as good as whitening formula gets. Or you could, of course, just give up smoking and coffee, etc – after all, willpower is free!

Further experiments: Arm & Hammer Enamel Care toothpaste may not make the same whitening claims as SwissDent, but its formulation feels similar, leaving your teeth feeling clean but protected by a very thin coating of the paste (£2.33 for 75ml, www.superdrug.com).