Experts say that brushing your teeth more than twice a day may be harmful rather than beneficial.
The guidance is contrary to years of advice, which encouraged children to brush teeth after every meal.
With the increasing rates of tooth decays, experts blame "five portions of fruit and veg a day".
Dentists said that while fizzy drinks and chocolates were the worst causes, fruit and fruit drinks were also high in acid, which leads to tooth decays.
Moreover, foods covered in sauces or dressings are also acidic.
They showed the effects of acid erosion on children's teeth at least once a week.
Though eating an orange is bad for erosion, it could worsen if children clean their teeth after every meal, as the acid has already softened enamel. oreover, a hard toothbrush would scratch away the softer surface and damage it even more.
According to a survey 53 per cent of five-year-olds had some form of the problem. Three in 10-12-year-old children were suffering worse forms of acid erosion, which could eventually change the shape, and texture of their teeth.
Professor Jimmy Steele of the School of Dental Sciences at The University of Newcastle has said that protection from an early age would help fight erosion.
"Adult teeth generally start to appear when children are six years old and need to last a lifetime," Daily Express quoted Steele, as saying.
"While children should not be discouraged from consuming acidic food and drinks, it is important for parents to take small steps to minimise the risk to their children's teeth.
"Encourage them to drink acidic drinks with a straw placed towards the back of the mouth away from teeth.
"And encourage children to avoid brushing their teeth immediately after consuming acidic food or drinks as this is when the enamel is at its softest.
"It's best to wait as long as possible after an acidic meal or brush beforehand," he added.