Teeth whitening 'fails to shine'

White teeth are universally desirable

People aiming for whiter-than-white teeth may have the smile wiped off their faces by research which shows many whitening products do not live up to their claims.

Health Which?, the magazine of the Consumers' Association, tested a range of products and found that at best they were backed up by little evidence that they worked.

Manufacturers were asked to produce evidence as to the effectiveness of their products.

In three of the products tested, independent dentists received no evidence the products helped whiten teeth.

You could be washing money straight down the plughole

Emma Copeland,
Health Which?

Eight products received a research rating - how well their claims were backed up - of 10%.

Four products received a rating of about 50%.

Teeth can become discoloured for several reasons, including age, diet and lifestyle.

Tea, coffee and smoking can cause surface (extrinsic) stains.

Staining

A person's health can affect the colour of the tooth itself (intrinsic stains). Some prescription drugs can also affect teeth colour.

William Hague shows off his pearly whites

Tooth whitening products are divided into those which promise to whiten, and some just claim to remove stains.

Stain removal often involves the use of abrasive agents that simply rub them off. Some contain detergents, say Health Which?.

Products designed to remove intrinsic stains can contain peroxides

Emma Copeland, principal researcher for Health Which?, said: "At best the products we looked at are unlikely to remove more than surface stains - and some of them may not even do this very well.

'Transient' benefits

"If you're serious about whitening your teeth, talk to your dentist first. Otherwise you could be washing money straight down the plughole."

A spokeswoman for the British Dental Association told BBC News Online: "Toothpastes help to clean teeth and can remove some stains. Teeth can also be cleaned professionally by a dentist or hygienist to remove stains.

"However, cleaning - getting back to the tooth's natural colour - needs to be distinguished from tooth-lightening using bleaching agents.

"Toothpastes alone cannot offer more than a transient cosmetic benefit."

She added that "whitening toothpastes" can be beneficial in that they encourage people to brush their teeth, and said consumers could buy a small tube of a product to see if it worked.