Picture: File Energy drinks should be banned in schools

Energy drinks are ‘readily available legal highs’ and should be banned from schools, according to a teaching union.

Stimulants in the drinks are said to contribute to poor behaviour in pupils.

The National Association of Schoolmasters Union of Women Teachers (NASUWT) said children see them as ‘just another soft drink’.

But a 500ml can may be cheaper than bottled water and contain 160mg of caffeine – the same as two shots of espresso coffee.

This is well above the 105mg a day limit recommended by experts for children aged 11.

Darren Northcott of the NASUWT said teachers have raised the issue of poor behaviour as a result of pupils consuming ‘excessive quantities’ of energy drinks bought easily from school vending machines. He said: ‘They are popular among young people who often think they are just another soft drink, and young people and parents are often not aware of the very high levels of stimulants that these drinks contain.

‘The NASUWT has always been clear that drinks with high levels of sugar should not be sold on school premises.’ Popular brands include Red Bull, Lucozade, Monster Energy and Mountain Dew. Some 500ml cans contain the equivalent of more than 13 teaspoons of sugar, which is the same as four cans of cola.

Norman Lamb, a former Liberal Democrat health minister, said: ‘Given epidemic levels of consumption among under-16s we have to consider banning the sale of these drinks to that group.’

Separate research by UK universities found children were buying energy drinks for as little as 25p and opted for them over water or coke because they wanted to ‘fit in’ or ‘look tough’.

Many cans carry warnings that they are not recommended for children because of the high levels of caffeine. They have already been banned from several schools. The Small Heath secondary school in Birmingham, imposed a ban in 2014.

At the time the head said pupils had been drinking Red Bull and other products for breakfast. The Haydock High School in Merseyside also introduced a ban in 2014 and detentions dropped by a third in two terms.