Cooking vegetables in different ways could cut down on tooth decay, scientists have claimed.
Dental erosion can lead to the need for expensive treatment
Certain methods of cooking them can make vegetables as acidic as fizzy drinks, according to a new study.
Researchers at Dundee's dental school made the discovery while experimenting with the vegetarian dish ratatouille.
They found that, compared with stewing, oven-roasting significantly increased the acidity of vegetables such as green peppers, aubergines and courgettes.
Dr Graham Chadwick, who led the study, said its findings could be used by dentists when advising patients on ways to fight dental erosion.
The problem is caused by the direct contact of acid with the teeth, which destroys tooth tissues - leading to the need for expensive dental treatment.
'Risk' to vegetarians
Dr Chadwick said: "The acidity of ratatouille prepared by oven-roasting is the same as that of some carbonated drinks that, when consumed in excess, are believed to contribute to the development of dental erosion."
The research, published in the European Journal of Prosthodontics and Restorative Dentistry, came following claims that vegetarians are at higher risk of dental erosion because of the large quantity of naturally acidic fruit and vegetables they eat.
The researchers also found the cooking method had no impact on the acidity of tomatoes or onions, but roasting resulted in more acidic aubergines, green peppers and courgettes.
Red peppers, they also discovered, were more acidic when stewed.