It has been claimed that smoothies are good for health
Dentists have warned the current popularity of fruit smoothies could lead to widespread tooth damage.
It was claimed last week that the fruit drinks could be twice as healthy as first thought.
But dentists warn that the beneficial effects of boosting consumption of fruit are likely to be far outweighed by damage the drinks cause to teeth.
They warn that the high levels of sugar in the drinks can promote decay without good dental hygiene.
Dr Nigel Carter, chief executive of the British Dental Health Foundation, said: "Fruit smoothies are becoming increasingly popular and the fruit content can make them seem like a good idea.
"However, they contain very high levels of sugar and acid and so can do a lot of damage to the teeth."
Dr Carter said research had linked poor dental hygiene and tooth decay to a range of serious health conditions, such as heart disease, respiratory disease, and diabates.
However, a survey of 1,000 people conducted by the British Dental Health Foundation and the company Oral B found more than 30% of people think fruit smoothies are actually good for the teeth.
Dr Carter said: "While fruit smoothies can be a good way to get people to consume more fruit, the high concentration of sugar and acids means that they can do real damage to the teeth if sipped throughout the day.
"Every time you sip on a fruit smoothie your teeth are placed under acid attack for up to an hour, so constantly sipping on these drinks can cause the protective enamel to erode, causing pain and sensitivity. It can also lead to decay."
Dentists advise the best policy is to brush your teeth before drinking fruit juice, as this helps protect against the damaging effect of the acid contained in the juice.
Brushing immediately after drinking juice can cause damage as the tooth enamel can be weakened by the acid content.
The survey found that many people engage in very poor dental habits, with a significant number admitting to using every day items such as hammers, screwdrivers, scissors and lollipop sticks to pick food from between their teeth - risking cuts and infection.
More than a quarter (27%) of respondants said they had opened a bottle with their teeth.
More than one in ten (13%) of respondants admitted to flossing their teeth while driving.
Dr Carter said: "People are putting themselves at risk with these shocking habits - yet around 85% of people are completely unaware of the link between the health of the mouth and the health of the body."
"Gum health, in particular, is very important and has been linked to a range of conditions. However, people are risking their gum health by picking and flossing without paying the necessary care and attention."